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WESCO APDRP (Technical Specification for 33/11KV Primary Sub-Station)

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WESCO

TENDER DOCUMENTS

FOR SUPPLY & ERECTION OF 33/11KV Primary Sub-Stations along

with associated 33KV & 11KV Link Line

LAST DATE OF SALE : 11 AM 19.03.07

DUE TIME AND DATE OF SUBMISSION : 1 PM on 20.03.07

TIME AND DATE OF OPENING: 4 PM on 20.03.07


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PART – I : SCOPE AND CONDITIONS.

1: SCOPE : This specification provides for the design, engineering , construction, of 33/11KV primary S/S. It also includes commissioning and maintenance of the facilities up to operational acceptance by the employer. The scope of work under this specification covers the following : 1: Establishment of new Substations. New Substations will be of the following : These will typically be with 3.15 MVA to 8MVA transformers protected by 33 KV outdoor open type circuit breakers. There will be an indoor metalclade. 11 KV switch board with full circuit breakers for protection of transformers, out going feeders and a bus bar sectionaliser circuit breaker. The contractor shall be fully responsible for providing all equipment, material, system and services excepting those specifically excluded, which are required to complete the construction and successful commissioning of the substations in all respects. The substations shall conform in all respects to the higher standards of engineering, Design, Workmanship to this specifications and the latest revision of relevant standards at the time of offer and the S.E. ( Planning and Works ), Head of the APDRP shall have the power to reject any work or material, which, in his judgment is not in full accordance there with . The development of the substation is shown in single line diagram. The development of the standard substation shall be based on these . The substation configuration for any individual substation may vary with some possible variations. These diagrams are meant to be illustrative of the variations in substation configurations required, but they are not meant to be exhaustive. Contractors should note that the configuration of any individual substation may vary from the substation schematics illustrated and the nos. and configurations of equipment may be varied to suit individual substation requirements. 2: DETAILED SCOPE OF WORK: 2.1: Survey : The contractor shall be responsible for surveying the substation site, including site soil tests as specified and forward a complete survey report to the S.E.(Planning and Works). 2.2 : Supply and Erecting Works : The contractor shall be responsible for design, engineering, manufacture, type testing, routine testing, supply, transportation, handling, storage at site, erection, site testing, commissioning and maintenance of plant and equipment until operational acceptance of the facilities in accordance with conditions of contract and the stipulations under various sections of this specifications of the following items:

• Power Transformers • Isolators. • Voltage transformers • Surge arresters • Post insulators


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• Control, Protection, Announciation and metering systems(except for 11KV indoor metal clad switch board ).

• Insulator strings and other hardware fittings • Bus bar conductor and conductor accessories • Power and control cables • AACDC System.

- AC distribution boards - DC distribution boards - Battery and battery chargers - 33/0.433 KV, 100 KVA auxiliary transformers.

• Fire fighting system and equipment. • Structure for _ Switchyard gantries/ portals _ Equipment ( Other than outdoor 33 KV and 11 KV circuit breakers and CTs. ) • Testing and maintenance equipments • Lighting of substation area and substations buildings • Earth mat and associated earth connection materials. • Mandatory spares for substation equipment being supplied under this contract. • Special tools, operating rods and any other equipment necessary for operation

and maintenance. • Any other equipment required to complete the substation.

The equipment offered shall have been successfully type tested and the design shall have been in satisfactory operation for a period of not less than two years on the date of bid opening. Compliance shall be demonstrated by submitting with the bid (i) authenticated copies of type test reports and (ii) Performance certificates from the users. However, where the bidder offers similar but not identical equipment to that which has been type tested, the difference shall be stated in the test certificate schedule, whether to accept or reject the offered equipment and type test data presented shall be at adjudged by the S.E.(Planning and Works), Head Of the APDRP . 2.3 Civil Works :

The contractor shall be responsible for design, engineering, supply of all materials including cement and steel, consumable items, as per specification and approved drawings for civil works of the substations including but not limited to the following.

• Site development including clearing and leveling. • Fencing of substation area and other areas as required by the safety regulation of

local, state and central governing bodies. • Approach road to the substation area. • Road within the switchyard. • Drainage system of the substation area • Foundations of all equipment in line and transformers outdoor bays e.g. circuit

breakers, CTs, Isolators and VTs.. • Foundation and Plinths for transformers. • Cable trenches with covers • Control room building or switchgear cum control room building • Water and sewarage services • Pavings and surfacing of the substation area.


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2.5: Other responsibilities of the contractor : The contractor shall be responsible for the design and engineering including determination and implementation of protection relay settings, over all co-ordination with internal and external agencies, project management, training of Employer’s manpower, loading, un loading , storage at site, inventory management at site during construction, any necessary dismantling and re erection of installations, handling, transporting to final destination, obtaining statutory authority clearance for successful erection, testing and commissioning of the substations. The Contractor shall also be responsible for overall security of the site and until operational acceptance by the Employer. 2.6: Specific exclusions : The following items of work are excluded from the Contractor’s scope of work unless otherwise specifically stated in the contract documents : * Substation site selection. * Land acquisition 2.7: Interface points for line terminations at the substation : The scope of this specification includes provision of substation bus bar/gantry structures. Termination of overhead lines including tension insulators and tension fittings at these structures shall be part of the line work. Interconnection of the line conductor to the substation equipment shall be part of the substation work included in this specification. Where 11 KV overhead lines are to be terminated at or near the boundary, of the substation and connected to the indoor 11 KV switch board through a short length of under ground cable, the provision of 11 KV cable and cable terminations at both ends shall be part of the substation work included in this specification. Where, however an 11 KV cable runs for a distance greater than 10m. beyond the substation boundary, the provision of 11 KV cable and cable terminations at both ends shall be part of the contract for provision of 11 KV lines and cables and out side the scope of this specification. 2.8: Limit of Contract : The scope of work shall also include all work necessary for successful operation, commissioning and handing over the facilities whether specifically mentioned or not, and in general is to be carried out by the contractor in accordance with stipulations in the conditions of contract. 3. STANDARDS: Except where otherwise specified or implied, the facilities shall comply with the latest applicable additions of the International Electro-technical Commission ( IEC) or International Organization for Standardization (ISO) recommendations or the relevant Indian Standard (IS ) listed in the individual technical specifications and as follows : IEC/ISO Indian Standard Title Indian electricity rules 1956 ( as amended up to 1996 ) IEC 71/DIN Minimum clearances and protective barrier clearances in power installations with rated voltage above one KV. VED 0101 IEC 158 Low voltage control gear. IEC 227 IS 1554 PVC insulated cables up to and including 1.100V.


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IEC.296 IS 335 New insulating oils. IS 1866 Code of practice for maintenance and supervision of Mineral insulating oil in Equipment. IEC 337 IS 6875 Control switches IEC 439 IS 8623 Low voltage switchgear and control gear Assemblies IEC 502 IS 1554 Extruded solid dielectric insulated power Cables for rated voltages from 1 KV up to 30 KV. IEC 529 IS 13947-1 Degrees of protection provided by enclosures(IP Code) IEC 865 IS 13235 Short circuit currents- calculation of effects IS 806 Code of practice for use of steel tubes in general building Construction. IE C 947-2 IS 13947-2 Low voltage switchgear and control gear circuit breakers. IS 1161 Steel tubes for structural purposes. ISO 630 IS 2062 Steel for general structural purposes. IS 800 Code of practice for general construction in steel. IS 802 Code of practice for use of structural steel in overhead transmission line towers. IS 7205 Safety code for erection of structural steel work. IS 456 Code of practice for plain and reinforced concrete. IS 269 33 Grade ordinary port land cement. IS 1489 Portland pozzolana Cement. IS 383 Coarse and fine aggregates from natural sources for concrete. IS 432 Mild steel and medium tensile steel bars and hard drawn steel wire for concrete reinforcement. IS 1199 Methods of sampling and analysis of concrete. IS 11384 Code of practice for composite construction in structural steel and concrete. IS 2502 Code of practice for bending and fixing of bars for concrete reinforcement. IS 1786 High strength deformed steel bars and wires for concrete reinforcement. IS 2911 Code of practice for design and construction of pile foundations. IS 9103 Admixtures for concrete. IS 2645 Integral cement water proofing compounds. IS 3043 Code of practice for earthing.


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ISO 1460/ IS 2629 Specification for hot dip galvanized coatings on iron and BS 729 steel articles. IS 2633 Method for testing uniformity of coasting of zinc coated particles. IS 2551 Denger notice plates. IS 2171 Portable fire exitinguishers, dry powder ( cartridge type). IS 2878 Specification for fire extinguisher, carbon dioxide type. IS 1888 Method of load test on soils. IS 1892 Code of practice for subsurface investigations for foundations. IS 2131 Method of standard penetration test for soils. IS 2131 Code of practice for thin walled tube sampling for soils. The bidder may, however submit for approval, equipment or materials conforming to technically equivalent national standards, The bidder shall furnish a copy of the alternative standard proposed along with his bid. Whether to accept or reject any alternative standard shall be adjudged by the S.E.(Planning and Works), Head of the APDRP. If the alternative standard is in a language other than English, an English translation shall be submitted with the standard. In the case of conflict the order of precedence shall be 1) IEC or ISO Standards, 2 ) Indian Standards3) Other alternative Standards. Reference to a particular standard or recommendation in this specification does not relieves the contractor of the necessity of providing the facilities complying with other relevant standards or recommendations. 3.1 Associated Technical Specifications. The Contractor’s proposal shall be based upon the use of equipment and materials complying fully with the requirements specified here in and with all the detailed specifications and requirements contained in the individual accompanying Technical Specification as follows : * Technical specification for 33KV isolator and earthing switch * Technical specification for 11KV isolator * Technical specification for 33KV gang operated air break switch * Technical specification for 33KV and 11KV drop out fuses * Technical specification for 33KV and 11KV voltage transformers * Technical specification for 33KV and 11KV surge arresters * Technical specification for all aluminum Alloy conductor * Technical specification for overhead line fittings * Technical specification for 33KV ,11KV and LV insulators * Technical specification for 33KV and 11KV control protections and metering panel * Technical specification for battery charger and DC distribution board * Technical specification for power and control cables * Technical specification for installation and maintenance of power and control * Technical specification for line support poles and cross arms * Technical specification for 11KVA,33KV/LV auxiliary transformer This list is not to be considered exhaustive and reference to a particular specification in this list or this specification does not relieve the contractor of the necessity of providing the goods and services complying with other relevant specifications or recommendations. For goods and services not specified in this specification, the contractor shall provide equipment of a quality comparable to other specified equipment and complying with the relevant international or Indian standards.


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It is recognized that the contractor may have standardized on the use of certain components, materials, processes or procedures different from those specified in this document. Ultimate proposals offering similar equipment based on the manufactures standard practice will also be considered, provided such proposals meet the specified design standard and performance requirement and are acceptable to the S.E(Planning and Works). 4. SERVICE CONDITIONS. The service conditions shall be as follows : * Maximum altitude above sea level 1,000m. * Maximum ambient air temperature 50°C

* Maximum daily average ambient air temperature 35°C * Maximum ambient air temperature 5°C * Maximum temperature attainable by an object exposed to sun 60°C * Maximum yearly weighted average ambient temperature 32°C * Maximum relative humidity 100% * Average number of thunderstorm days per annum(isokeraunic level) 70 * Average number of rainy days per annum 120 * Average annual rain fall 150cm. * Table of wind pressures applicable in Orissa.

Wind Zones LIS 802 (part.I):1995 Part-I Orissa.

2 Kg/m2 3Kg/m2 5Kg/m2

Terrain Category – I 57.4 73.1 94.3 Terrain Category-2 49.3 62.6 80.9 Terrain Caategory-3 35.6 45.3 58.4 Wind Zones IS-802(Part-I):1977 Light Medium Heavy Wind pressure on Towers Kg/m2 130 195 260 Wind pressure on Conductors Kg/m2 43 45 52

Indoor material and equipment shall be designed and protected for use in buildings, which occasionally may be wet and damp. 5. SYSTEM CONDITIONS. The equipment shall be suitable for installation in supply system of the following characteristics : * Frequency 50Hz * Nominal system voltages 33KV 11KV 400/230V * Maximum system voltages 33KV system 36KV 11KV System 12KV LV System 476V * Minimum LV Voltage 340 V * Nominal Short circuit levels 33KV Systems 25kA 11KV Systems 12.5kA * Insulation levels 1.2/50 µs impulse withstand voltage

( Positive and Negative polarity) 33KV System 170KV 11KV System 75 KV * Power frequency one minute withstand Voltage ( Wet and Dry) rms. 33KV System 70KV 11KV System 28KV LV System 2KV


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* Neutral Earthing arrangements 33KV Systems Solidly earthed. LV System Solidly earthed. PART 2: TECHNICAL 6: GENERAL REQUIREMENTS: The switching schemes adopted for substations shall be as shown on the attached single line diagrams,. The contractor shall propose the most economical substation layout that meets the desired degree of operational flexibility, reliability, service continuity and expandability. The contractor shall submit design considerations establishing the above and suggestions for the Employers approval. It is the responsibility of the Contractor to prepare a detailed layout showing the manner in which the various items of equipment offered can be accommodated to best advantage within the available area. The arrangement shown on the attached single line diagrams may be modified as necessary to accommodate the various items, e.g. different types of disconnector provided the basic principles are maintained. The Bidder is at liberty to offer substation arrangements based on significantly different principles where it is considered that these offer economies or technical advantages. It is emphasized, other arrangements being submitted solely as alternatives to the main offer. 7. DESIGN PARAMETERS: The substation design should be such as to minimize the no. of levels of conductor. All materials and equipment for use in the substation shall be suitably rated to meet the site conditions specified in the schedules. Vehicle access to permit the transport of major equipment shall be provided. Access for vehicles which required the de-energisation of circuits shall be kept to a minimum and avoided where ever possible. Where the connection to the substation is from over head line to outdoor station equipment, over head line conductors will be strung from the line terminal structure to the substation gantry structure. The over head line conductors complete with tension insulators, line tee off clamps and compression fittings ( bi-metallic) where necessary will be supplied and erected as part of the line work and do not come within the scope of this specification. The Contractor shall provide facilities on the gantry structure for the fixing of the tension insulators and shall arrange branching of conductors in to the substation from the over head line conductors. Where 11KV over head line are to be terminated at or near the boundary of the substation and connected to the indoor 11 KV switch board through a short length of under ground cable, the line terminal structure, surge arresters will be provided under a different contract. The provision of 11 KV cable and cable terminations at both ends shall be part of the substation work and within the scope of this contract. Where however an 11 KV cable runs for a distance greater than 10m beyond the substation boundary, the provision of 11 KV cable and cable terminations at both ends shall be part of the contract for provision of 11 KV lines and cables. Where a 33 KV overhead line is provided with an earth wire, the earth wire will be extended in to the substation as part of the line work and the substation gantry structure shall be arranged to receive this. Substation equipment, structures, roads, concrete cable roughs and drains shall be laid out in neat and organized manner to meet the employes requirements, facilitate movement of vehicles and ensure safety of personnel and equipment. The lay out shall be flexible to accommodate various orientations or positions of bus bars, internal road ways and buildings depending on the site locations relative to road ways and line approaches. 7.1 Site sizes and basic layout requirements: For substation a standard site size of 40m. should be assumed and the contractor shall design the layout as follows: The substation layout is to be capable of accommodating, without the erection of additional bus bar/gantry structures or building extension :

• An outdoor 33 KV bus bar with sectionalizing air break switch :


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• Up to two 33 KV line feeders ( one each side of the sectionalizer) with either air break switches or circuit breaker protection

• Up to two 33/11KV transformers ( one each side of the sectionalizer) each with 33 KV circuit breaker protection.

• An 11KV indoor metal clad switch board with two transformer circuit breakers, six 11 KV feeder circuit breakers and one sectionalizer circuit breaker..

In addition the design should allow space for future bus bar extension to accommodate additional 33 KV feeder with air break switch or circuit breaker protection on each side of the 33 KV bus bar. The control switch room shall be large enough to accommodate an additional 11 KV feeder panel on each side of the bus bar sectionalizing circuit breaker. In some cases, circumstances may force selection of smaller sites e.g. 30m. x 30m. In such cases the additional space for further 33 KV bus bar extension may not be practicable and it so, the design need only allow for as much of the above stated future development as is feasible . In some cases also the site may be rectangular rather than square, which may require alternation in the relative positioning of buildings and equipment. 7.2 Bus bar construction. The bus bar shall be design to with stand the maximum ambient temperature and short circuit conditions given in the sections on service conditions and system conditions in this specification. The continuous current rating shall be so design that no portion of the bus bar is un duly loaded or over heated. The Contractor shall submit design calculations in support of the various dimensions of the bus bar for approval by the S.E. (Planning & Works). 7.3 Interlocking principles : The design of the interlocking scheme shall be based up on the following principles :

• Isolators are capable of switching only the negligible capacitive currents of associated connections or of switching circuits where no significant change in the voltage across the terminals of each of the poles of the isolator occurs on opening or closing.

• Isolators have neither load making nor breaking capacity. • Isolators are not capable of making or breaking transformer magnetizing current. • Circuit breaker shall not be used as points of safety isolation, this is the function

of isolators or load break switches which have a visible break. • It shall not be possible to operate any isolator unless its associated circuit breaker

is open. • Operation of an isolator shall be prevented when its associated earthing switch is

close. • Operation of an earthing switch shall be prevented when its associated isolator is

closed. • Line isolator or feeders which can be energized from a remote source can not be

fully inter locked with that source and shall carry a warning notice to this effect. Similar notices shall be applied to earth switches.

7.4 Clearances : Clearances shall be adequate so that there is no flash over between live parts and grounded metal objects in the worst environment conditions including 100 percent humidity as described in the clause on service conditions in this specification. The minimum electrical clearances for 11 KV and 33 KV outdoor equipment shall be :

Minimum Electrical Clearances in Primary Substation:


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11KV outdoor equipment 33KV outdoor equipment. Phase to phase – rigid conductors(mm)

230 325

Phase to earth – rigid conductors (mm)

180 325

Live unscreened parts to ground level(mm)

2750 3700

Sectional clearance(mm) 2600 2800

The values quoted above are based on DIN VDE 0101. IEC 71 and Indian electricity Rules, 1956 ( as amended up to 1996). Except for arcing horn gaps they are to be considered as the absolute minimum values to which must be added adequate tolerances for construction inaccuracies and movement due to wind or any other factor which may act to reduce the clearances during service. The following are recommended phase spacing values for various items of outdoor equipment.

11KV out door equipment 33KV outdoor equipment Ph- Ph Ph – E Ph- Ph Ph – E

Strung bus bars and non rigid

connections(mm.)

900 850 1200 1050

Isolators(center to center)(mm)

760 1200

Gang operated air break

switches(center to center)(mm)

760 1200

The substation and all support structure and pedestals shall be designed to satisfy these requirement. Passageways providing access for operational and maintenance activities in switch rooms shall have minimum dimensions of one thousand mm. wide and two thousand mm. high . This is applicable to the passage way behind the 11 KV metal clad switchgear and shall be applied also to the space between and around meter and relay cabinets. 8. ISOLATORS. The support structures shall be design to accommodate isolators, load break switches or air break switches as required initially or in the future. Where a 33 KV feeder is equipped with circuit breaker protection, an isolator ( disconnector) with earthing switch shall be provided on the line side of the circuit breaker. An isolator with out earthing switch shall be provided on the bus bar side. Where an 11 KV feeder is equipped with circuit breaker, an isolator without earthing switch shall be provided on the line side of the circuit breaker or auto recloser. An isolator will not normally be required on the bus bar side of the circuit breaker. Where primary 33/11KV transformer is provided with open terminal circuit breaker protection, and isolator without earthing switch shall be provided on the bus bar side only of the 33 KV and 11KV circuit breakers, Isolators are not required between the circuit breaker and the transformer. Isolators shall be pedestal mounted or alternatively may be mounted horizontally or vertically in a bus bar gantry structure depending on the design adopted by the contractor. This shall conform in every respect to technical specification for 33 KV isolator and earthing switch or technical specification for 11 KV isolator.


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9. CIRCUIT BREAKERS,CURRENT TRANSFORMERS AND AUTO RECLOSERS; Out door and indoor circuit breakers are supplied with 230V. AC motor wound spring charged mechanisms. The design and provision of foundations, erection, all connection and remote control from an indoor control, protection and metering panel of the circuit breakers and current transformers shall be within the scope of this contract. Where outdoor current transformers are provided with cores which are not used in the installation, the contractor shall never the less connect these cores via control cable to terminal racks on the control panel in the control room. In substation there will be 11KV indoor metal clad switch boards complete with voltage and current transformer, control protection, annunciation and metering. These will normally have two incoming transformer feeders, four to eight outgoing 11 KV feeders and a bus bar sectionalizer all with full circuit breaker protection. The storage at site, erection site testing, commissioning, operation and maintenance of all of the above equipment until handover shall be within the scope of this contract. 10. AIR BREAK SWITCHES : Gang operated air break switches will be required on certain feeders, as sectionalisers in out door bus bars or as protection in conjunction with fuses on the 33 KV side of smaller primary transformers. Two types of air break switch will be used.

a. Non load break air break switches. These have capacity to break small currents such as transformer magnetizing current or line charging current. They can only break small active loads of the order of 10A. Most air break switches will be of this type.

b. Load break switches. These are gang operated air break switches fitted with interrupter heads. In addition to the duties of an ordinary air break switch they have the capability to break normal load current. Load break switches will usually be used for out going 33 KV feeders.

In order to distinguish between the two types the use of the term Air Break Switch will normally be used to denote the non load break type. The other type will be referred to as Load break Switch. The type of required in each location will be as detailed in the schedules. Air break or load break switches may be either horizontally or vertically mounted on gantries or portal structures depending on the layout and design adopted by the contractor. They shall conform in every respect to Technical specification for 33KV Gang operated air break switch or to technical specification for 11 KV Gang operated air break switch. 11. VOLTAGAE TRANSFORMERS. Outdoor voltage transformers (VTs) will be required on the 33 KV bus bar in some primary substations. These are required to provide secondary voltage for instrument meters and relays. The VTs shall conform in every respect to technical specification for 33 KV and 11 KV voltage transformers. The 33KV voltage transformers shall be connected directly to the 33 KV bus bar. The 11KV voltage transformers shall be connected on each side of the bus bar sectionaliser as indicated in the single line diagrams . The contractor shall design and provide suitable mounting arrangements for the VTs. Which may be mounted in the bus bar structural frame or on separate pedestal supports depending on the design adopted. The secondary connections of each set of three VTs shall be brought to a marshalling box mounted as close to the VTs as possible but at a height where it can be easily accessed from ground level. The box shall contain a gland plate and gland for entry of control cables terminal block fuses for protection of VTs secondary windings and earthing links to facilitate star connection. It shall be possible to work on the marshalling box in safety with the VTs live. The marshalling box shall be hot dip galvanized in accordance with the section own


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Surface, Treatment in this document and shall have a degree of protection equal to IP 54 of IEC 529 or IS 13947 part I. The Contractor shall make connections from VTs to all panels requiring VT supplies including but not limited to the on load tap change control panels and all panels with volt meters, energy meters voltage relays or directional protection. 12. SURGE ARRESTERS: Metal oxide gapless heavy duty station class surge arresters shall be provided in primary substations conforming in every respect to technical specification for 33 KV and 11 KV Surge Arresters. All 33/11KV transformers shall have surge arresters on the primary and secondary sides. They shall be fitted as close as possible to the transformer, mounted where possible on brackets attach to the transformers tank or radiators. The Contractor shall be responsible for provision of suitable mounting arrangements and for adequate earth connections from these surge arresters to the station earth grid.

In substations where 11 KV over head lines are connected to the indoor 11KV switch board through a short length of under ground cable, 11 KV station class surge arresters are to be installed on the terminal structure of the over head line. The supply and erection of these surge arresters shall be within the scope of this contract.

13. OUTDOOR BUS BARS AND BUS BAR CONNECTIONS. 13.1. Bus bar materials. The bus bar shall be made of all aluminum alloy conductor (AAAC). They shall be designed to withstand the maximum ambient temperature and short circuit conditions given in the sections on service conditions and system conditions in this specification. The continuous current rating shall be so design that no person of the bus bar is unduly loaded or overheated. The following sizes of conductor shall be used for bus bars. * 11 KV bus bar including sectionalizer connections, 232mm² AAAC. * 33 KV bus bar 232 mm² AAAC. There shall not be any mid span conductor joints in strong bus bars. The conductor sag shall not exceed of conductor span when carrying full load current. The Contractor shall submit design calculations in support of the various dimensions of the busbar for approval by the S.E. (Planning & Works), Head of the APDRP. The following conductor sizes are to be used for connection from bus bars to equipment :

• 33KV line bay connections – 232 mm² AAAC. • 33KV transformer connections – 232mm² AAAC • 11KV transformer connections to cables- to provide minimum rating of 12MVA.

The materials used for bus bars and connections from bus bars to equipment shall conform to the following specifications:

• Technical specification for all Aluminum Alloy conductor (AAAC) • Technical specification for overhead line fittings • Technical specification for 33KV ,11KV and LV insulators.


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13.2: Standard Outdoor Bus bars. 13.2.1. 33 KV bus bar : The design and installation of the standard bus bars are to be such as to accommodate equipment for a station consisting of two 33KV line feeders, a bus bar sectionalizer and two 33/11KV transformers provision is to be made for fitting voltage transformers to either side of the 33KV bus bar and for a 33KV/LV auxiliary transformer. The 33kV bus bar structure installation shall include all necessary structures for the following equipment.

• The Bus bars. • Bus bar sectionalizing switch. • Bus bar isolators for two 33/11KV power transformers. • Bus bar isolators or air break switches or load break switches for two 33KV

lines. • Set of three bus bar VTs mounted on either side of the bus bar. • Air break switch and drop out fuses for 33KV/LV station transformer mounted

on either side of the bus bar. • Line isolator with earth switches and line lead ins for two 33KV lines. • Any additional structures required for completion of the 33KV side.

14. PROTECTION CONTROL AND METERING.

In substations with indoor 11KV switchgear the associated control protection announciation and metering will be integral with the 11KV switch board. The installation, commissioning and maintenance of the 11 KV switch board until operational acceptance shall be within the scope of this contract. The contractor shall be responsible for the design, supply, installation and connection of control, protection and metering panels for protection, control, annunciation and metering of circuit s with outdoor 33KV or 11 KV circuit breakers. A number of different types of panel will be required depending on the configurations of various types of substation. The actual numbers of 33KV and 11KV circuit breakers to be controlled will be as detailed in the schedules for new substations. Typical combinations of outdoor circuit breakers to be controlled would be as follows;

• One or two 33KV transformer CBs • One or two 33KV transformer CBs. Plus one or two 33KV line CBs • One or two 33KV and 11KV transformer CBs • One or two !1KV transformer CBs

The Panels shall be designed and manufactured to comply in all respects with Technical specification for 33KV and 11KV control protection and Metering panel. The contractor shall determine appropriate settings for all protection relays in the .substation .These settings shall take account of sub station maximum and minimum fault levels, short circuit rating of equipment, full load and over load rating of equipment. High voltage circuit shall be protected in such a way that reliable high speed selectivity for all network fault is assured and achieved, as far as possible, isolation of the minimum amount of plant in the event of a fault and backup in the event of failure of primary protection. The protection equipment installed under the contract shall be compatible with the protection of the over all net work, and the setting ranges and sensitivities provided shall be such that coordinated selective settings are attainable for the composite system. The protection shall remain stable without spurious operation and without damage to the relays during normal disconnecting and switching operations and during faults within the design short circuit level for each net work element. No spurious tripping shall occur on a healthy feeder in the event of a fault on a parallel feeder. The contractor shall be fully responsible for the accuracy logic and performance of the relay system.


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Protection scheme shall be designed to provide secure and dependable protection on each net work element. The reliability of all relays used shall be proven at least two years service experience. The Contractor shall submit to the S.E. (Planning & Works) details of all the proposed settings at least eight weeks prior to the proposed date of commissioning of the substation. The proposal shall include time/current characteristic curves for the various device settings proposed, plotted on a log- log scale. The proposal shall be subject to approval by the S.E. (Planning & Works). Circuit breakers supplied by the employer will come with local/Remote selector switches for use during maintenance work. When these switches are in the local position protection will not trip the circuit breaker. The contractor shall include in the facilities indication on the appropriate Alarm annunciation panel when local is selected. 15. PRIMARY TRANSFORMERS;

Primary 33/11KV power transformers are to be ONAN cooled with on load tap changers and remote tap change control panels. The ratings of transformers are 3.15 MVA, 5.0 MVA and 8.0MVA.

The transformer remote tap change control panels( one per transformer) will contain the following facilities:

• Raise and lower push buttons or control switch. • Independent Master follower selector switch. • Remote tap position Indicator • Necessary audible and visual alarms.

* Out of step relay with two spare contracts ( 2NO and 2 NC) . In addition to the above the remote indoor panel will have the following trip and non trip and non trip alarm facia windows with five spare windows suitable for 24 V DC. 1 Oil temperature alarm. 2. Oil temperature trip. 3. Winding temperature alarm 4. Winding temperature trip. 5. Buchholz alarm 6. Bechholz trip. 7. Surge relay trip (OLTC gear) 8. Low oil level alarm. 9. Tap changer out of step alarm 10. Failure of supply alarm. It shall be the responsibility of the contractor under this contract to design and lay transformer foundations and plinths assemble and install the transformers, install the remote tape change control panels in the control room building lay and connect all the necessary control cabling for transformer alarms, trips and tap change control commission and maintain the transformers up to operational acceptance by the employer. Wiring of trip signals from the tap change control panel to the transformers control panel master trip relay whether existing or installed as part of this project shall be included in the scope. Where one or both of the existing circuit breakers are of the out door kiosk type with self contain control and relay functions the contractor shall install the necessary wiring to trip the circuit breakers from the Buchholz or temperature trip signals on the tap change control panel. 16. BATTERY, BATTAERY CHARGER AND DC DISTRIBUTION. A reliable 24 volt direct current supply shall be provided for control protection alarm and indication. The battery shall be installed in a separate room provided with acid proof flooring and with an exhaust fan. The battery charger and DC distribution board shall be installed in the control room.


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The battery, battery charger and DC distribution board shall comply in every respect with technical specification for Battery, Battery charger and DC distribution board. This specification provides for two sizes of battery, battery charger and DC distribution board, 100 ampere hour. The contractor shall however assess the load requirement of each substation, check the specified battery and battery charger for adequacy and submit calculations to the S.E. (Planning & Works). It shall be the responsibility of the contractor to ensure that the batteries and battery chargers supplied are adequate for the envisaged duty. 17. AC AUXILIARY SUPPLY AND DISTRIBUTION BOARD.

The AC electrical substation services shall be in accordance with all the relevant standards, shall satisfy the requirements specified in this document and shall be designed to operate in the environmental conditions specified in the sections on service conditions and system conditions. 17.1 Auxiliary Transformer. In substations the contractor shall supply a 100KVA three phase 33 KV /LV auxiliary transformer for substation heating, lighting and auxiliary equipment. This transformer shall comply with technical specification for 100KVA 33KV/LV transformer.

The contractor shall also be responsible for design of foundation, installation and connection of the transformer to the 33 KV outdoor bus bar through suitable fuses and an air break switch

17.2 AC distribution board :. The contractor shall design the LV distribution system to ensure that the voltage supply limits are maintained at all times and that the distribution boards and cabling are never over loaded. The low voltage AC supply from the auxiliary station transformer shall be brought through 4x120mm2 PVC insulated cables to a suitably rated moulded case circuit breaker (MCCB) in the main distribution board in the control room. The MCCB shall conform to IEC 947-2 or IS 13947-2. Low voltage switchgear and control gear. A number of single phase loads shall be fed from the distribution board through individual single pole miniature circuit breakers. The miniature circuit breakers used shall be standardized as far as possible to facilitate interchangeability and reduce the number of spares required. Distribution cable sizes shall be such as to ensure that voltage drop between the supply point and any point of utilization is less than 2.5%. . The A.C.distribution board shall conform to IEC 439 or IS 8623. The distribution board with MCCB and miniature circuit breakers shall be housed in the AC distribution cabinet. This cabinet shall be a free standing self supporting structure or alternatively may be designed for wall mounting. The cabinet shall be manufactured from specially selected smooth finish cold rolled sheet of thickness not less than 2.5mm and shall be sufficiently reinforced to provide a structurally rigid enclosure. The cubicles shall have leveled surface, be resistant to vibration and ensure rigidity during transportation, installation and service. The equipment shall be completely metal clad and shall be dust, moisture and vermin proof. The cabinet shall have a degree of protection IP-51 conforming to IEC 529 or IS 13947 Part I . All doors and removable covers shall be fitted all round with neoprene bonded gaskets. Ventilating louvers shall be provided with screens and filters. Screens shall be made of brass G.I. wire mesh or stainless steel mesh. The panels shall be provided with lockable doors at the front and rear giving easy access for the inspection , replacement and repair.


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All wiring shall be carried out with 650 volt grade single core stranded annealed and tinned copper conductor wire with PVC insulation and shall be fire retardant, flame, vermin and rodent proof. Each wire shall be continuous from end to end without any joint in between. The minimum number of strands per conductor shall be three. The size of stranded copper conductor used for panel wiring shall be suitable to meet the load conditions but shall be not less than 2.5mm2 per lead. The PVC insulated wires shall conform to IEC.502 or IS.1554. A voltmeter, an ammeter and a kilowatt hour meter shall be provided to measure the voltage at the distribution board and the current and energy flowing into it from the auxiliary supply transformer. 17.2.1 Cable entries : The cable entries to the panel shall be from the bottom. The plate of the panels shall be fitted with removable gland plates of adequate size for fixing cable glands. The necessary number of cable glands with shrouds to suit the external cables to the panel shall be provided. The cable glands shall be screw type made of electroplated brass and shall be suitable for PVC insulated cables conforming to IEC 502 or IS.1554 17.2.2 Mounting : An equipment on the front of the panel shall be mounted flush in such a fashion that removal and replacement can be carried out individually with ease. Equipment mounted inside the panel shall be so located that terminal and adjacent devices are readily accessible without the use of special tools. The terminals shall be suitably marked and the marking shall be clearly visible. The devices mounted on or inside the panel shall be provided with their inscription labels clearly visible. 18. CONTROL CABLES AND WIRING ; The contractor shall ensure that the cross section of the wiring is adequate for the operating current conditions and shall submit load calculations demonstrating the adequacy of these conductors. The special requirements of the circuit designs given below shall be met. Where wiring is connected to removable connections or movable equipment or where repeated movement may occur, such apparatus mounted on a hinged panel outdoor the conductor used shall be of the multistranded flexible type. Each multiple cable shall be used for one type of duty and at one supply voltage level. Cables used shall also be on a switchgear bay basis where possible. The requirement shall be reflected right through the station control room. Cables and wires for any particular circuit shall have a rated duty and a dielectric test level at least matching the minimum of the equipment to which they are connected. Control cables and wires shall have copper conductor with a minimum operating temperature rating of 85 °C for PVC insulated cable and minimum cross section of 2.5mm ². Control cables and wires carryings CT circuits shall have a minimum cross section of 2.5mm ² but the size shall be increased if required to maintain the CT burden or secondary voltage within specified limits. In addition cables and wires used for connections between switch gear and the bay marshalling point shall be further protected against mechanical damage by the use of metallic conduits or trunking .


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All control cable and wire shall conform in every respect with technical specification for power and control cables. 18.1 Physical layout : Routing and arrangement of cables shall be planned to provide an orderly formation free from un-necessary bends and crossings permitting the removal of any one cable without undue disturbance to adjacent once. All control cable shall be physically separated from high voltage power cables and their routes chosen to minimize the pickup of induced voltages liable to cause damage or interference Cables shall be installed so that no temporary or permanent bends are made which are sharper than those recommended by the manufacturer and confirmed as acceptable by test. There shall be no joints in cables where both ends are terminated within the substations. 18.2 Cable laying : Control cables shall not be laid direct in the ground but in cable trenches with removable covers. Where cables run cross roads or enter buildings the cables may be run in pipes. The type and lay out of ducts and pipes shall be subject to the approved routine arrangement. After installations of all electrical cable pipes two mops of appropriate size connected one to each end of an iron mandrel shall be passed twice through each way to clean the pipes and to remove any foreign matter which may have entered. If any obstruction or other defect be discovered it shall be removed or rectified forth with. The pipes shall be brushed clean and their mouths temporarily but effectively sealed until require for cable installation. Additional pipes for future use shall be sealed effectively with PVC caps to prevent ingress of moisture. All pipes and ducts shall be brushed clean immediately prior to the installation of cables. The contractor shall deal with and dispose of water and other extraneous material so as to avoid risk of damage to cables. The proposed method of cooling and the cooling arrangements shall be subject to the approval of the S.E. (Planning & Works), Head of the APDRP. Where necessary the cable shall be lubricated to facilitate drawing in. The lubricant used shall have no deleterious effect on the cables or other surrounds. At the point of cable entry in to the pipe or duct a bell mouth of suitable soft material shall be provided to prevent damage to the cable during direct entry. Indoor cables shall be run in ducts in the floors. These ducts shall have removal covers. Where cables enter a building or pass from room to room within a building free retardant barriers shall be provided. 18.3 Corrosive action : Every precaution shall be taken to ensure that cables and accessories are not installed in a manner or under conditions likely to cause electrolytic or other corrosive action or damage or be detrimental to the performance of the cables during operation. 18.4 Supports : The contractor shall supply and install all the supports, racks, trays, cleats, saddles, clips and other parts required to carry and secure the cables without risk of damage in a neat and orderly manner. The spacing of all supports , racks, cleats, saddles and clips shall be subject to the approval of the S.E. (Planning & Works). Support structures for cables shall be free from rough edges and sharp corners. If such support structures are of steel they shall be hot dip galvanized.


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Cable connections to kiosk boxes, cabinets etc shall be at least 300mm over ground. Vertical portions of cable runs shall be supported by clamps, saddles on ladder racking or in conduit or trucking. All cables shall be securely supported at a point not more than 1.0m from their termination. 18.5 Terminations : Wires shall not be tee connected or spliced between terminal points. Suitable glands shall be used on cable entries to mechanism boxes, cabinets and kiosks. All stranded or flexible wires shall have crimped connectors fitted at terminal points. Crimped connectors on solid wires shall not be acceptable. Cables and wires with conductor of cross section area 2.5mm² or greater shall be terminated in terminals of the clamping type where the screw does not bear directly on the wire when tightened by a screw driver. The use of any alternative type of terminal shall be subject to the approval of the S.E. (Planning & Works). For terminations at panels, kiosks and cabinets file terminals shall be used and these shall be arranged in rows on a mounting rail. The file terminals shall be spring loaded for clipping into position. Means for isolating circuit such as the drop link type file terminals shall be provided on all AC and DC supply circuits. File terminals on current transformer secondary circuit shall be provided with short circuiting devices and with devices for plugging in ammeters and test equipment. Ten per cent spare terminals shall be provided on each file terminal rack. In all cases the sequences of the file terminals shall be such that the junction between multicore cables and the terminals is effected with a minimum of crossover. 18.6 Identification : Cables shall be fitted with numbered identification tags at termination points. All internal wires in cabinets kiosks and panels shall be identified at each end by means of a sleeve indelibly marked with an identification number. The sleeves shall be such that they remain fixed to the wire when the wire is removed from the terminal. All cable core shall also be identified at each end by means of a captive sleeve indelibly marked with an identification number referenced to the terminal to which it is connected. The ferrules on all wires directly connected to circuit breaker trip coils shall be coloured red and marked trip. 18.7 Damage during installation : Any damage to cables or accessories during installation shall be made good by the contractor free of charge and to the satisfaction of the S.E. (Planning & Works). 19. POWER CABLES ; In substation with indoor metal clad switch boards the contractor shall supply and install aluminium XLPE insulated underground cables to connect the power transformers to the switch board and to make the connections from the switch board to 11 KV over head line terminal structures at or near the substation boundary. The following sizes of cable are to be used :

• For offloading each 33/11KV transformer – 6x1x300mm2 – 11KV single core XLPE insulated cables.

• For offloading 11 KV out going feeders 3x185mm2- three core XLPE insulated cable .

The LV cable offloading the auxiliary transformers in substation shall be 4x120mm2 PVC insulated cable which shall also be supplied and installed by the contractor.


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All underground cables including joints and terminations shall comply with technical specification for power and control cables. The cable trenching laying and installation shall comply with technical specification for installation and maintenance of power and control cables. 20. SUBSTATION LIGHTING AND POWER CIRCUITS An adequate level of lighting shall be provided both indoors throughout the building and outdoors to allow normal operational duties and emergency repair work to be carried out at night. Outdoor lighting shall be high-pressure sodium vapour type. At least four individual outdoor lights shall be provided, placed so as to provide adequate illumination to the whole compound. Lamps should be safely replaceable with out the necessity to disconnect high voltage circuits. In substation control rooms there be a minimum of eight 2x40W twin tube fluorescent light fitting with grilled cover, suspended from the ceiling above the height panels. They shall be located such that sufficient working illumination is provided at the front as well as at the rear of the panels. At least four ciling fans of 1,400mm sweep shall be fixed in the control room at appropriate locations. Adequate lighting fitting shall be provided in the Office/Store, battery rooms and toilet. Emergency lighting fed from a battery charger unit separate from the station battery shall be provided to permit safe working in the substation in the event of failure of normal lighting. All exits from the station building shall be indicated by illuminated EXIT signs which shall remain lit for one hour after any AC failure. A minimum of five single phase 230V. AC convenience 15amp. sockets shall be provided in substation indoor control switch rooms. Two 15amp. sockets shall be provided in the office store. Two single-phase 15amp.230V.AC sockets shall be provided one at each side of the out door switchyard in convenient locations for supply of power for tools and other equipment. A source of three-phase power suitable for transformer oil filtrations plant shall be provided adjacent to the transformer foundations. Out door power supply fitting shall be weather proof. An average lighting level of not less than 50lux shall be provided in the area of the site occupied by the out door equipment & on foot paths & road ways. 21. GENERAL REQUIREMENTS FOR OUTDOOR STRUCTURES 21.1. Design of structures The substation structures shall be design to carry the equipment and associated connections, insulator sets, earth conductors and all fittings under all specified conditions of service of operation and loading. Vertical support structures for out door equipment and busbars/gantries may be steel, reinforced concrete, prestressed concrete or lattice steel structures. Horizontal supports and bracing shall be of galvanized rolled steel sections or galvanized lattice steel sections. • Rolled steel joist or concrete pole structures shall comply with technical specification for line support poles

and cross arms. • Pipes supports used for supporting equipment shall be designed for the worst combination of dead loads,

erection load, wind load, short circuit forces and operating forces acting on the equipment and associated busbars as per IS:806 and IS:1161.

• Lattice steel supports structures shall be designed in accordance with the requirements of IEC 826 or IS 802 and requirements specified in the section on Lattice Steel supports structures in this specifications.


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The substation busbar/gantry structure shall be design to carry the tension down lead spans from overhead line terminal structures, taking account of the details and locations of the line terminal structures and the type of conductor used on the overhead line in order to do so. They shall be design for a maximum wind pressure for wind zone 5. Terrain category 2 if design is to carry equipment or materials on more than one side of the structure shall be design to cater for all possible stages of equipment erection, installation and maintenance. The substation busbar/gantry structure shall be designed to terminate the overhead line down lead spans which may enter at angles of ± 30° horizontally and ± 15° vertically. 21.2. Conductor spacing and clearances Structures shall be dimensioned to maintain the specified minimum phase to earth, phase to phase and insulation height clearances under conditions of maximum conductor swing and sag. The spacing between individual conductor, phase and the clearance between the clamps, arcing horns, jumper loads or other live metal and the structure steel work and other obstacles under specified conditions of temperature and loading shall not be less than the specified values. 21.3. Applied loads The assumed maximum simultaneous loading on the substation structures shall be as follows: 21.3.1. Wind loads The normal wind load shall be the stated wind pressure acting on the whole projected area of the phase and earth conductors and where applicable, the horizontal resultant of the maximum line and earth conductor tensions, together with the stated wind pressure on 1.5 times the projected area of the members of one phase of the structure plus the projected area of the plant being supported. 21.3.2. Electro mechanical Electro dynamic forces due to short circuit conditions, snatch forces, Aeolian vibration and other similar nature loads shall be computed and applied for design of structures. The different mechanical effects due to short circuit current shall be estimated as per IEC – 865. 21.4. Construction The structures shall be of an approved design and constructions. All stressed numbers (tension and compression) of steel structures shall consist of rolled steel sections unless otherwise approved. No bolt hole shall be more than 1.5mm. larger than the corresponding bolt diameter. As far as possible, bolt heads, rather than nuts, shall be on the outer or upper faces of structure connections. Where the structure is to take the down lead connection from over head line terminal structures, suitable provisions shall be made to accept the line insulator fittings. Means shall be provided for fixing and bounding GI flat strip to the structure at a minimum of two points. Earth connections shall be made to a vertical face, clear of the ground, foundation bolts shall not be used for their attachment.


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21.5. Material All rolled steel sections, flats, plates and bolt and nut bars used shall consist of steel manufactured by an approved process and shall be to the requirements of ISO 630 or IS 2062 (minimum yield strength 255N/mm²). the steel shall be free from blisters, scales, laminations and other defects. Steel sections shall preferably be British Standard or Metric standard being bolted up. Drifting or reaming of holes will not be allowed. Built members shall, when finished, be true and free from all kinks, twists and open joints and the material shall not be effective or strained in any way. Except where specified to the contrary, all steel used in lattice steel structure shall be hot dip galvanized after all sawing, shearing, drilling, punching, filing, bending and machining are completed. Galvanizing of all material shall be in accordance with the requirements of this specification as indicated in the section on surface treatment. 21.6. Nuts, Bolts, Washers and other fasteners. All nuts, bolts, washers and other fasteners used in support structures shall comply with the requirements. 21.7. Foundation bolts. All foundation bolts for lattice structures and pipe structures and elsewhere are to be supplied by the Contractor and shall be embedded in first stage concrete while the foundation is cast. The Contractor shall ensure the proper alignment of these bolts to match the Holes in the base plate. The Contractor shall be responsible for the correct alignment and leveling of all steel works on site to ensure that the towers/structures are plumb. All foundation bolts shall be fully galvanized so as to achieve 0.8Kg./m² of zinc coating as indicated in the section on surface treatment in this specification. The contractor shall provide templates for all stanchion bolt spacings. Holding down bolts, assemblies, templates, tubes and washers shall be delivered to the site in sufficient time to position and build them in to the foundations, Boxing out for bolts shall not be permitted. The projection of threaded portions of bolts above the foundations level shall be adequate to properly secure the nuts. 22. CIVIL WORKS 22.1. Scope The Contractor will be responsible for the design as well as the construction of the following:

Site preparation; Fencing of substation/switchyard area and other areas as required by safety regulations of location state

and central governing bodies; Foundations for substations buildings, structures, transformers, switchgear and other equipment; Substation structures and building; Approach road, Roadways, Pavings and surfacing within the substation; Cable trenches with covers; Water and sanitary conveniences; Drainage and septic tanks; Perimeter fencing and gates;


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22.2. Site survey 22.2.1. Construction conditions Prior to bidding the Contractor shall examine the general conditions under which the contract will be carried out and shall take these in to account in presenting his bid. 22.2.2. Land survey Prior to construction the Contractor shall carry out topographical surveys of each site. The purpose of survey will be to:

Define in detail the immediate areas of the substations both in level and location; Establish site boundaries; Locate and comment on conditions of existing approaches and accesses to the various site; Pick up any relevant details such as vegetation, habitation, stream beds and other geological features;

22.2.3. Survey plans A location plan to scale 1:50000 and site plan to scale 1:100 shall be prepared for each site showing the above details. Five copies of such plans shall be presented to S.E. (Planning and Works). 22.2.4. Soil investigation The Contractor shall carry out soil investigation at each site appropriate to the type of structure to be erected. The tests and methods shall comply with the requirements of the latest editions of IS 1888, IS 1892, IS 2131, IS 2132, IS 8763. The minimum requirement shall be 2No. 4m. deep trial pits at each site. The ground at each site shall be investigated for chlorides and sulphates and any other chemicals detrimental to normal Portland cement. 22.3. Design 22.3.1. Liability The design of all the works shall be the responsibility of the contractor and this specification shall be used as the basis for the design. 22.3.2. Calculations The Contractor shall present to the S.E. (PLANNING and WORKS) as part of the submittals after award all the design calculations for approval. Such approval by the S.E. (PLANNING and WORKS) shall not relieve the Contractor of any of his responsibilities under the contract. 22.3.3. Standards The design shall in all ways be compatible with supply and environmental conditions pertaining to the site involve.


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22.4. Description of Work 22.4.1. General requirements This sub clause describes in greater detail the scope of the civil and building works and sets out any special features to be incorporated in to the Contractor’s design. 22.4.2. Construction services The Contractor shall provide all services such as water, electricity and sanitary conveniences necessary for the proper execution of the works. The Contractor shall provide a suitable permanent 5m. road way from the nearest public road to the site. On the site, roads shall be provided to facilitate delivery of transformers and other heavy items of plant. 22.4.3. Site preparation The site shall be provided with a uniform cross fall in the same direction as the natural drainage path of the surrounding area. Areas not to be subject to traffic loads or floor slab load shall be compacted to 85% modified maximum density. Fill beneath future roads and buildings shall be compacted to 95%. The Contractor will be responsible for all materials employed and for location of soil heaps and borrow pits. 22.4.4. Foundation Design Foundation shall be design to enter for the following type of ground. • Normal dry soil.

Cohesive or non-cohesive soils which are present without encountering sub-soil water table within the first 1.5meters of the foundation

• Wet soil (Ground type A) Wet earth due to sub-soil water table met at less than 1.5meters below the ground level and in locations where surface water is prevalent for long periods of time.

• Black cotton soil (Ground type B) Soil of a clayey type, not necessarily black in colour, which shrinks when dry and swells when wet, resulting in differential movement for designing the foundation at such locations, the soils are to be considered as wet soil.

• Fissured rocks (Ground type C) Decomposed or fissured rock, hard gravel, kankar, lime stone, laterite or any other soil of a similar nature.

• Hard rock (Ground type D) Rock, which requires chiseling, drilling or blasting for excavation, Rock-anchoring techniques are required to prevent uplift forces.

Foundation and where necessary, plinths shall be provided for transformers, 33KV and 11KV switchgear and other equipment as specified. All foundation shall be capable of resisting all the design loadings including dynamic loads due to circuit breaker operation and shall be designed to keep differential and total settlements or other movements within acceptable


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limits. The Contractor shall demonstrate that the stability of building and structures as a whole (or any part of them) and calculated factors of safety, conform to the approved codes of practice. Where the ground is excavated for any reason below the underside of the proposed foundation the void shall be filled with weak concrete. No foundation shall be constructed on fill material. All transformers foundations and plinths shall be constructed in reinforced concrete. Reinforced concrete support structures and foundations shall conform to the section in this specification of foundations/reinforced Concrete Construction. 22.5. Control/Switch room buildings. 22.5.1. General requirements Design & Construction of the control room or Control/switch room for substations shall be in the scope of this Contract. In some cases, there will be an extension of the existing control/switch room building which will be needed to meet requirements. The Contractor shall design and construct any necessary extension without disturbing the existing system of cable trenches or damage to the existing buildings. All structures shall be designed to carry the loads imposed by the structure itself, together with live loads in accordance with an approved standard or code of practice. The building design shall also take into consideration the layout of the panels, switchboards, switchgear and other equipment in order to allow enough area for the future extension of the substation. In the layout and the design of buildings particular attention must be given to fire prevention and the safety of the substation occupants at all times. All concrete floors must be constructed in moisture proof concrete treated with a surface hardener to reduce dust. Ducts shall be provided for cable access. Capacity for the full development of the station shall be provided. Following the installation of any equipment, the walls through which cables or wires pass shall be effectively rescaled to exclude water, rodents and vermin. Room height shall be governed by the criteria that there should be at least 1m. clearance between the top of the switchgear and ceilings. Kiln burnt briks of class 1 grade, size 250x125x75mm. are to be used for construction of the control/switchroom building walls. The walls of the building shall be not less than 250mm. in thickness. The floor shall be at least 300mm. above the finished level of the substation switchyard. Cement plaster of ratio 1:4 shall be used for wall surface plastering. Floor, Wall and ceiling finishes shall be fireproof or flame retarding. The need for maintenance must be kept to an absolute minimum and finishes and fixing of building components must be of appropriately high standard. The roof of the building shall consist of cast in situ R.C.C. slabs. Extra heavy water proofing treatment shall be done after grading underbed with 1:4 cement sand plaster of 25mm.thickness. The under bed shall be laid to provide an ultimate run off gradient of 1:120. the extra heavy treatment shall consist of the following layout.

Prime the surface with bitumen prime at rate of 0.4kg/m² minimum; Hot applied bitumen at rate of 1.6kg/m² minimum;


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Hessian-base-self-finished felt, type 3 grade 1; Pea sized gravel at the rate of 0.006 cubic metres per m²; Finally a 1:2:4 screed of foam concrete, 40mm. thick shall be laid over the roof, sloped for adequate

disposal of rain water with a run off gradient of not less than 1:100 Rainwater down pipes must be external to the cladding of the main building. Gutters shall be so constructed that water shall not enter the building in the event of blockages. 22.5.2. Substation building “The standard size building for substations shall be sized to provide one switch cum control room, one office cum store room, one battery room & one toilet room. The office cum store room shall be not less than 15m² in area. The toilet room shall have a WC & wash basin.” “The control cum switch room shall be of such a size to accommodate control metering & protection panels for four 33KV feeder equipped with circuit breakers & two 33/11KV transformer circuit breakers, two 33KV transformer tap changer control panels, & an 11 (eleven) panel 11KV indoor metal clad switch board consisting of eight 11KV feeder panels (up to four on either side of the bus coupler), one 11KV bus-coupler & two transformer 11Kv panels. A clear space of not less than 2 shall be provided in front of the control panel & switchgear panels. An open space of 1m minimum is to be provided behind & at the sides of control panel boards for staff access & egress both for safety & maintenance requirements. For the purpose of bidding it may be assumed that the 11KV switchboard will have a straight line configuration with individual panels not more than 850mm wide x 1900mm deep x 2800mm high. All station auxiliaries, including but not limited to the battery & charger system shall be also sized to provide for the above development. The battery room shall be provided with acid proof flooring & with an exhaust fan.” Adequate natural lighting shall be provided to allow all normal operations during daylight. A minimum of six windows of size 2m. wide x 1.3m. high shall be provided in the control/switch room. Each window shall have a steel frame with glass panes and opening sections not more than 0.5m. in width . a canopy over each window of RCC (1:2:4 mix) 100mm. thick shall be provided to project at least 600mm. from the surface of the wall and extend 200mm. beyond the edge of the window on each side. The control room shall have two steel doors. One of which shall be of adequate width to permit easy entry of control panels, switchgear and equipment. 22.6. Roadways, Pavings and surfacing Road within the compound shall be 3m.wide and shall provide access to the control room or Control/switch room all switchgear bays and transformers. The Contractor shall provide 5m. wide access roads to the site from the nearest public road. Where a water dyke, drain, canal or river is to be crossed, the Contractor shall be responsible for the design and construction of the crossing to the requirements of the relevant water authority. A separate price schedule item is included for crossing of water channels of up to 4meters wide. 22.7. Cable trenches Control cables and power cables from transformers shall be run in trenches within the substation building and compound. The 11KV feeder cables may be direct buried. Cable trenches of at least 600mm. in width shall be made of kill burnt bricks of class one grade, size 250 x 125 x 75 mm. and finished with 1:6 cement plaster with a 1: 100 slope for drains of rain water. Intermediate holes are to be made in the side walls of the trench for this purpose. The walls of the cable trench shall project at least 50mm.


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above the finished level of hard granite stone in the switchyard. The cable trench walls shall have galvanized steel brackets embedded in one side at intervals of not more than 0.5m. for the purpose of supporting control cables. There should be space in the trenches to allow a slack loop of at least 1 meter in 11KV cables just before entering the control room area. Within buildings cable trenches shall have chequer plate covers while the outdoor covers shall be of reinforced concrete design (1:2:4mix) not less than 50mm. in thickness. Cable ducts passing beneath roads shall consists of 150mm. diameter pre cast concrete or 150mm PVC pipes and encased in a surround of lean concrete. 22.8. Water Supply The Contractor shall be responsible for making available to the new substation an adequate water supply system, for toilet and wash up facilities. The system shall consist of a 0.5m³ header tank supplied, if necessary, from a 2m³. ground level tank by an electric pump. 22.9. Drainage and septic tanks The building shall be provided with gutters and rainwater down pipes, but their will be no system of road gullies for collection of surface water Foul drainage shall terminate at the nearest public sewer (where available) or in suitable dimension septic tanks which shall be of water tight construction and sited at least 20m. from the substation building. Septic tank should discharge to rubble filled soak ways and shall be so constructed as to facilitate regular emptying. Drains shall be laid with regular gradients such that full flow velocity exceeds 0.75m./s. and main holes shall be provided at each change in direction. No drain shall be less than 150mm. diameter in section and cover shall be at least 1.2m. beneath roads. 22.10. Fencing and gates 22.10.1. Substation enclosure The entire substation shall be fenced around by means of a brick wall not less than 250mm. thick and 1800mm. high. Strengthening pillars approximately 375mm. square shall be placed at intervals of not more than 3.54m. the surface of the wall shall be covered with 1:6 cement plaster. The top of the wall shall be finished off in inverted “V” shape with 150mm. long vertical spikes 12mm. in diameter placed at 150mm. intervals in order to deter intrusion. 22.10.2. Gates. Galvanised steel gates 4m. in width shall be provided at the entrance to the substation. The gates shall be fitted with spikes or suitable means to hinder access and shall be comparable in quality and security to the adjacent wall. Gates shall be fitted with strong lock bolts having eye padlock attachments. The locking arrangement shall not provide a climbing aid or vantage point for intruders. Gates shall be galvanized after fabrication and welding Gates shall open inwards and shall be fitted with galvanized malleable iron hinges, latch and latch catch. The latch and latch catch shall be suitable for attachment and operation of a padlock from either side of the gates.


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Gates shall be fitted with galvanized chain hook or gate hold back to hold gates open. Double gates shall be fitted with a center rest and drop bolt to secure gates in the closed position. 23. WORK IN EXISTING SUBSTATIONS Existing buildings may be reused. The works shall include all alterations to existing buildings, foundation, internal roads, access roads, cable ways, ducts and other facilities necessary to complete the civil works of the substation in all respects. Existing cable openings or trenches shall be used where possible when designing the switchgear boards and structures. In existing substations there may be no cables or cable trenches between outdoor equipment and the control room. The Contractor shall be responsible for installing any necessary cable trenches and cables in these substations. 23.1. Extension of existing busbar structures. In designing and planning any necessary extension to existing 33KV or 11KV busbar structure, the contractor should take into account that most existing structures have RSJ up rites mild steel channel beams and cross members and that the extension will have to fit in with what is already there. Any cross beams or members in the extension shall be hot galvanized in accordance with the section on surface treatment in this document even if the corresponding existing members are not. 23.2. Installation of circuit breakers and Reclosers Installation in existing substations of additional or replacement circuit breakers or reclosers shall be included in the scope of this contract. The circuit breakers and current transformers together with supporting structures shall be supplied. The Contractor shall be responsible for the design and provision of foundations, erection, all connections and remote control from and indoor control protection and metering panel for the circuit breakers and current transformers. The circuit breaker shall be required for 33KV or 11KVside of transformer, 33KV feeders or 11KV feeders. In general it is assumed that transformer circuit breakers will be installed without a requirement for additional structures. However in some installations there may be a requirement for conductor support structures to ensure clearance or to prevent clashing. The Contractor shall propose the most economical solution, for example using the same structure to support lighting arrestors. Where circuit breakers or reclosers are to be installed on existing lines the Contractor shall make the best use of existing structures to support line or busbar isolators. Otherwise installation of circuit breakers or reclosers shall be as specified for new sub-stations. During the survey the Contractor shall determine if additional support structures are required and include them in the list of items required to complete the work. The Contractor shall justify the requirement for any additional structures with sketches and explanations and calculation if required by the S.E. (PLANNING and WORKS), Head of the APDRP. The installation of the additional structures shall be subject to the approval of the S.E. (PLANNING and WORKS).


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23.3. Survey of Works to be carried out in existing Sub-Stations. The Contractor shall survey each substation requiring extension or operating and shall submit proposals to the S.E. (PLANNING and WORKS) to an agreed program. The proposals shall include all details required to the following; • Full details of all the works necessary to complete the required facilities; • Appropriate site plans drawings and schematics clearly setting out the existing arrangement and the

alterations required; • Supporting Calculation; • A list of all the price schedule items and quantities required to complete the facilities; • A detailed time bound program for completion of the facilities; The proposal shall be subject to the approval of the S.E. (Planning and Works) before works begin. 24. FOUNDATIONS / REINFORCED CONCRETE CONSTRUCTION 24.1. General Worked covered under this clause of the specification comprises the design, supply and installation of foundation and other RCC constructions for switchyard structures, equipment supports, drains, transformers, marshalling kiosks, auxiliary equipment, buildings or for any other equipment or service and any other foundation required to complete the work. Concrete shall conform to the requirements mentioned in IS 456 and all tests shall be conducted as per relevant Indian Standard Codes. If the site is sloped the foundation height shall be adjusted to maintain the exact level of the top of structures to compensate such slopes. The switchyard foundations plinth and building plinth shall be minimum 300mm. above finished ground level. A minimum 75mm. thick lean concrete (1:4:8) shall be provided below all foundations and trenches to provide a base for construction. Concrete made with Portland slag cement shall be carefully cured and special importance shall be given during the placing of concrete and removal of shuttering. The design and detailing of foundation shall take full account of and cater special importance shall be given during the placing of concrete and removal of shuttering. The design and detaining of foundation shall take full account of and cater for, approval soil data. Sub-soil conditions all possible critical loads and the combinations thereof. 24.2. Cement. The cement to be used shall be best quality of its type. All cement shall be sampled and tested in accordance with Indian Standards.

a) Portland Cement used in concrete shall confirm to IS: 269. b) Pozzolana cement used in concrete shall conform to IS : 1489.


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High alumina cement shall not be used. 24.3. Delivery and storage of cement. The cement shall be delivered to the work site in bulk or in sound and properly sealed bags. While cement is being loaded or unloaded whether conveyed in vehicles or by mechanical means, and during transit to the concrete mixture, it shall be protected from the weather by effective coverings. Efficient screens are to be supplied and erected to prevent wastage of cement during strong winds. If the cement is delivered in bulk, the Contractor shall provide at his own cost approved soils of adequate size and number to store sufficient cement to ensure continuity of work. The cement shall be placed in these soils immediately it has been delivered on the site. Suitable precautions shall be taken during unloading to ensure that the resulting dust does not constitute a nuisance. If the cement is delivered in bags, the Contractor shall provide at his own cost perfectly waterproof and well-ventilated sheds having a floor of wood or concrete raised at least 150mm. above the ground. The sheds shall be large enough to store sufficient cement to ensure continuity of work. Each consignment of each type of cement shall be stacked separately therein. On delivery at the site the cement shall at once be placed in these sheds and shall be used in the order in which it has been delivered. All cement shall be used within 3 months of manufacture. 24.4. Aggregate. Coarse and fine aggregate shall conform to the requirements of IS: 383. Sampling and testing of aggregates shall be is accordance with the Indian Standard. Fine and coarse aggregates shall be obtained from the same source and the Contractor shall investigate that material from the source must be known to have a good record over a minimum of two years. Aggregate shall be hard and dense and free from earth, clay loam and soft, clayey, shaly or decomposed stone, organic matter and other impurities. 24.5. Storage of aggregates. The coarse and fine aggregates shall be stored on site in bins or on clean, dry, hard surface and be kept free from all sources of contamination. Aggregates of different gradings shall be stored separately and no new aggregate shall be mixed with existing stocks until tested and approved. 24.6. Approval of Supplies As soon as possible after the contract has been placed the Contractor shall submit a list giving details of the sources from which he propose to obtain concrete and mortar materials. Only materials from approved sources shall be brought to site, but the S.E. (PLANNING and WORKS) will be prepared to extend his approval to other satisfactory sources of supply which may be proposed by the Contractor. Approval of a source of supply shall not imply acceptance of material found not to conform to this specification. 24.7. Water. Water used for mixing concrete and mortar shall be clean, fresh water obtained from an approved source and free from harmful chemicals, oils, organic matter and other impurities.


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24.8. Steel bar reinforcement. Reinforcement shall comply with IS : 432. All bar reinforcement shall be hot rolled steel except where the use of cold worked steel is specified on the drawings or otherwise approved. The bars shall be round and free from corrosion, cracks, surface flaws, laminations, rough, jagged and imperfect edges and other defects. The bar reinforcement shall be new, clean and of the lengths and diameters described on the Drawings and Schedules. Bars shall be transported and stored so that they remain clean, straight, undamaged and free from corrosion, rust or scale. Bars of different diameters shall be separately bundled. 24.9. Steel fabric reinforcement. Unless otherwise specified or described on the drawings or in the bills of quantities, all fabric reinforcement shall comprise hard drawn steel wire fabric. Each consignment of steel fabric reinforcement shall be accompanied by a test certificate. Steel fabric reinforcement shall be new, clean free from corrosion, rust or mill scale and shall be transported to and stored on site so that it remains clean, undistorted and otherwise undamaged. Fabrics of different type or weights shall be separately bundled or rolled. 24.10. Bending Of reinforcement. All steel bars are to be accurately bent cold to the shapes and sizes indicated on the drawings and schedules unless otherwise approved. Re-bending of bars and bending in position in the works shall not generally be allowed. 24.11. Welding of reinforcement. Spot or tag welding for positioning bars in heavily reinforcement areas will only be allowed with the express permission of the S.E. (PLANNING and WORKS). Extension of lengths of reinforcement by welding will not be permitted. Welding will be approved only in low stress members, and tag welding will not be approved in any circumstances. 24.12. fixing of reinforcement. Before fixing in the works, bars shall be seen to be free from pitting, mud, oil, paint, loose rust or scale or other adherents harmful to the bond or strength of the reinforcement. Bars shall be fixed rigidly and accurately in position in accordance with the working drawings, unless otherwise approved by the S.E. (PLANNING and WORKS). Reinforcement at all intersection shall be securely tied together with soft annealed tying wire the ends of which shall be cut and bent inwards. Cover to the reinforcement shall be in accordance with this specification and sufficient spacers and chairs of precast concrete of approved design shall be provided to maintain the specified cover and position. No insertion of bars in previously placed concrete shall be permitted. Projecting bars shall be adequately projected from displacement. The fixing of reinforcement in the works shall be approved before concrete is placed. Measurement will be based on the calculated weights of steel actually used in tonnes corrected to second decimal place, no allowance being made for wastage.


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24.13. Formwork. Formwork shall be constructed from timber, metal lined as necessary for special finishes and designed with the quality and strength required to ensure rigidity throughout placing, ramming, vibration and setting of the concrete, without detrimental effect. Form work shall be erected true to line, level and shapes required using a minimum of approved internal ties. Faces in contact with the concrete shall be true and free from defect, jointed to prevent loss of water or fines, in panels or units which permit easy handling and designed to permit side forms to be struck independently of soffit shuttering, ties or spaces remaining embedded shall have the minimum cover specified for reinforcement. Forms for exposed concrete beams, girder casings and column shall provide for a twenty five (25) millimeter chamfer on external corners. Wedges and clamps shall be kept tight during vibration operations, before commencement or resumption of concreting, the interior of forms shall be cleaned and free of sawdust, shaving, dust, mud or other debris and openings shall be formed to facilitate this cleaning and inspection. The inside of the forms shall be treated with a coating of an approved substance to prevent adhesion. Care shall be taken to prevent this substance being in contact with the reinforcement. 24.14. Grades of Concrete. Concrete shall be either ordinary or controlled and in grades designated M – 10, M - 15 , M – 20 and M – 25 as specified in IS : 456 (1991). In addition, nominal lean mixes of 1:3:6 and 1:4:8 of nominal size 40mm. maximum e.g. for blinding concrete shall be used where specified. 24.15. Ordinary Concrete

a) General Ordinary concrete shall be used for all plain cement concrete work and where shown on drawing or allowed by the employer. Ordinary concrete shall not require preparation of trial mixes. In proportioning concrete, the minimum quantity of cement shall be as specified in this clause and the amount to be used shall be determined by actual weight. The quantities of fine and coarse aggregate may be determined by volume, but preferably by weight.

The water cement ratio shall not be more than those specified in IS: 456.

Minimum cement content specified for Different grades of concrete

Grade of Concrete Minimum cement content per m³ of

finished concrete

M 10 236 kg. M 15 310 kg. M 20 360 kg. M 25 410 kg.

M 310 500 kg.


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24.16. Controlled Concrete

a) General Controlled concrete shall be used on all concrete work except where specified otherwise. b) Mix proportions.

The mix proportion for all grades of concrete shall be designed to obtain strength corresponding to the values specified in IS: 456 for respective grade of concrete. Preliminary test, as specified in the IS code or as required by the employer, shall be carried out sufficiently ahead of the actual commencement of the work with different grades of concrete made from representative sample of aggregate and cement expected to be used on the job to ascertain the water cement ratio required to produce a concrete having specified strength and sufficient work ability to enable it to be well consolidated and to be worked in to corners of shuttering and around the reinforcement. c) Mix Design.

As a guide to perform the mix design properly, the relationship between water cement ratio, aggregate to cement ratio, workability and strength of concrete will be as per relevant Indian standard. Note :

1. The cement/total aggregate ratio is not to be increased beyond 1:9:0 without specific permission of the S.E. (PLANNING and WORKS).

2. It should be noted that such high aggregate cement ratios will be required for concretes of very low slump and high water cement ratios which may be required to be used in mass concrete work only. 3. The actual cement aggregate ratios are to be worked out from the specific gravities of coarse aggregates and sand being used and from trial mixes. Strength Requirements. The mix proportions for all grades of concrete shall be designed to produce the grade of concrete having the required work-ability and characteristics strengths not less than the value given below.

Strength Requirements Grade Designation Characteristic Compressive

Strength at 28 days. M 10 10 N/mm ². M 15 15 N/mm ². M 20 20 N/mm ². M 25 25 N/mm ².

Note : The strength of concrete given above is the 28days characteristic compressive strength of 15cm. cube. The type of cement used for the preparation of concrete shall conform to the specifications given in relevant Indian standard code.


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In exceptional circumstance the S.E. (PLANNING and WORKS) may accept concrete of lower strength then specified, which is other wise un acceptable according to the acceptance criteria IS : 456 provided the strength is never less than 80% of the specified strength. All concrete having strength less then 80% of that specified shall always be rejected. Payments for concrete of lower strength then specified then but accepted by the S.E. (PLANNING and WORKS) shall always be made at reduce rate prorate to the strength obtained. 24.17. Work-ability The work-ability of concrete shall be checked at frequent intervals by slump test, where facilities exist and if required by the S.E. (PLANNING and WORKS), Head of the APDRP alternatively the compaction factor test in accordance with IS : 1199 shall be carried out. 24.18. Mixing of Concrete The proportions of fine and coarse aggregate, cement and water shall be as determined by the mix design or according to fixed proportions in case of nominal mix concrete and shall always be approved by the S.E. (PLANNING and WORKS). The quantities of the cement, fine and coarse aggregates shall be determined by weight, the water shall be measured accurately after giving proper allowance for surface water present in the aggregate. Water shall not be added to the mix until all the aggregates constituting the batch are already in the drum and mixed dry for at least one minute. Mixing of each batch shall be contained until there is uniform distribution of materials, which shall be lest two minutes or at lest 40 revolution after all the materials and water are in the drum. Concrete shall be mixed using mechanical mixers unless otherwise approved by the S.E. (PLANNING and WORKS). When hand mixing is permitted by the S.E. (PLANNING and WORKS) for concrete to be used at unimportant locations, It shall be carried out on a water tight plat-form and care shall be taken to ensure that mixing is continued until the mass is uniform in colours and consistenty. In the case of hand mixing an extra 10% cement shall be added to each batch and additional cost due to extra cement shall be borne by the Contractor. 24.19. Conveying Concrete Concrete shall be handled and conveyed from the place of mixing to the place of final laying as rapidly as practicable by approved means before the initial setting of cement starts. Concrete should be conveyed in such a way which will prevent segregation or loss any of the ingredients. If segregation does occur during transport, the concrete shall be remixed. 24.20. Placing Concrete Formwork and reinforcement shall be approved by the S.E. (PLANNING and WORKS), before concrete is placed. The forms shall be well wetted and all savings, that and water that may have collected at the bottom shall be removed before concrete is placed. Concrete shall be deposited in its final position without aggregation re-handling or flowing. As far as possible concrete shall be placed in the formwork by means approved by the S.E. (PLANNING and WORKS), and shall not be dropped from a height or handled in a manner which may cause segregation. Any drop over 180cm. shall have to be approved by S.E. (PLANNING and WORKS). Once the concrete is deposited in its final position, it shall not be disturbed. Share should be taken to avoid displacement of reinforcement or movement of formwork. The placing of concrete shall be a continuous operation with no interruption in excess of 30minutes between the placing of continuous portions of concrete.


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After the concrete has been placed it shall be thoroughly compacted by approved mechanical vibration to a maximum subsidence without segregation and thoroughly worked around reinforcement or other imbedded fixtures in to the correct form and shape. Vibrators must be operated by experienced personnal and over vibration shall not be permitted. Care should be taken to ensure that the inserts, fixtures, reinforcement and formwork are not displaced or disturbed during placing of concrete. No concrete shall be placed in the open while it rains. If there is any sign of washing of cement and sand, the concrete shall be entirely removed immediately. Slabs, beams and similar structures shall be poured in one operation normally. In special circumstances with the approval of S.E. (PLANNING and WORKS), Head of the APDRP these can be poured in horizontal layers not exceeding 50cm., in depth. When poured in layers, it must be ensured that the under layer is not hardened. Bleeding of the under layer if any shall be effectively removed. 24.21. Construction joints. When the work is to be interrupted, the concrete shall be rebated at the joint to such shape and size as may be required by the S.E. (PLANNING and WORKS) as shown on the drawings. All vertical construction joints shall be made with stop board which are rigidly fixed and slotted to allow for the passage of the reinforced steel, constructions joints, if not described on the drawings shall be in accordance with the followings. In a column the joints shall be formed about 75mm. below the lowest soffit of the beams framing into it. Concrete in a beam shall be placed throughout a joint, but if the provision of a joint is un avoidable, the joint shall be vertical and at the middle of the span. A joint in a suspended floor slab shall be vertical at one of the quarter points of the span and at angle to the principal reinforcement. In forming a joint, concrete shall not be allowed to slope away to thin edge. The locations of constructions joints shall be planned by the contractor well in advance of pouring and shall be approved by the S.E. (PLANNING and WORKS). Construction joints in foundation of equipment shall not be provided without concurrence of the S.E. (PLANNING and WORKS). 24.22. Removal of formwork. Formwork shall be kept in position fully supported, until the concrete has hardened and gained sufficient strength to carry itself and any loads likely to be imposed upon it. Stripping must be effected in such a manner and such a time that no shock or other injury is caused to the concrete. The responsibilities for safe removal rests with the contractor, but the S.E. (PLANNING and WORKS) may delay the time of sticking if he deems it necessary. Minimum period, in the absence of agreement to the contrary, between completion of concreting and removal of forms are given below but due regard must be paid to the method of curing and prevailing conditions during this period.


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Removal of formworks Positions in Works Minimum period before striking

form work Removal of shuttering to sides of rafts, walls, beams and Columns. 2days

Removal of shuttering to slabs, beams and arches(props left under). 6days

Removal of props to slabs, beams and arches. 16days

Lifting of precast member. 16days 24.23. Load test for concrete The load test on concrete, if desired by the S.E. (PLANNING and WORKS), Head of the APDRP shall be carried as soon as possible after the expiry of 28days from the time of placing of concrete as per clauses 16.5 to 16.6 of IS: 456. the entire cost of the load testing shall be borne by the Contractor and if any portion of the structure found unacceptable under the relevant clause of IS : 456, the same shall be dismantled and replaced by a new structure as per specification at no extra cost to the employer. If during dismantling any of the adjacent structure gets damaged, the same shall be made good free of charge by the Contractor to the satisfaction of the S.E. (PLANNING and WORKS). 24.24. Finish of concrete surfaces.

i) Concrete cast against form works. The following finishes to concrete surfaces, in less otherwise specified or shown on the drawings, shall be as follows: Class A1: All permanently exposed surfaces, including exposed sides of foundation. Class A2: Surfaces to be covered by back fill, plasters or the like.

Class A1 surfaces shall be dense, fair, smooth, even free from honeycombing, water and air holes and other blemishes, true to line at surfaces and free from board or panel marking. They shall be of uninform colour. Rendering of defective surface shall not be permitted, and if order by the S.E. (PLANNING and WORKS), , the Contractor shall at his own expense cut out to expose reinforcement and make good any unsatisfactory work. All areas so treated shall be rubbed down and kept moist for several days. Class A2 surfaces shall be dense, even free from honeycombing, and true to line and surface. Any special finishes will be to details or instructions given by the S.E. (PLANNING and WORKS).

ii) Concrete not cast against formwork.

The following finishes shall be provided unless otherwise specified or shown on the drawings:- Class B1: All permanently exposed surfaces, including tops of equipment foundations, wall copings, window sills, pre cast items (except paving flags). Class B2: Paving flags and paths, floors and slabs to be surfaced with blocks, tiles or water proofing materials. Class B3: Roads, buried concrete and floors or slabs to be covered by screed.


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Class B1 surface shall fast be leveled and screened to produce a true surface, After the moisture film has disappeared and the concrete has harden sufficiently, the surface shall be finished with a steel trowel under firm pressure to give a smooth, dense, even and hard surface free from all marks and defects. Class B2 surface shall be leveled and screened to produce a true surface and be finished with wooden or steel float to give a level surface free from screed marks. Excessive floating shall be avoided. Class B3 surface shall be leveled and screeded to produce a true and uniform surface. 24.25. Curing of Concrete Curing may be effective by suitable impervious sheet materials or approved curing compounds. Curing compounds applied to surfaces which will be exposed in the finished work or which are to receive bounded finishes must be remove by light, even grid blasting. Curing periods for concrete shall follow the recommendations of the relevant Indian standards and shall be agreed with the S.E. (PLANNING and WORKS), Head of the APDRP. Where curing membranes are used they shall be compatible with waterproofing or other materials that may subsequently be applied to surface of the concrete. Concrete surfaces shall be kept covered and wet for at least 7 days after placing, or for such other period as may be approved. Covers used shall be of Hessian, sacking or other absorbent material and shall be kept wet continuously for the agreed curing period. Alternative proposed method of covering the concrete or ceiling in the moisture shall require approval. The Contractor’s attention is drawn to the particular importance of proper and adequate curing. Failure to carryout satisfactory curing can lead to cracking in the concrete. This in turn can lead to salt attack of the reinforcement and consequential failure of the structure. If cracks occur in structure which are sever enough to affect the structure, the Contractor shall cut out and replace the defective concrete at his own cost. 24.26. Holes, pockets, threaded inserts, etc. The threaded inserts for casting in to concrete shall be electro-galvanised and of malleable iron or mild steel. Holes, cavities and fixings shall be provided in the works only at the positions indicated on the drawings or as directed and they shall be incorporated as necessary during the work of concreting. Unless otherwise agreed tolerance in position of plus or minus (5) millimeters shall be allowed. Inserts and bolts shall be fixed square in the works by means of temporary bolts or nuts, and then concrete cast around them. The projecting portions of such fixing, and concrete within fifty millimeters of them, shall be bitumastic painted and all threads well greased on completion of the work. Holes and pockets shall be stripped drawn clean on completion. 24.27. Blinding Blinding concrete shall be made with nominal aggregate size of both 20mm. and 40mm. diameter. They shall be referred to respectively as grade M – 10 (1:3: 6) and (1:4:8). Under all foundations and else where as indicated on the drawings a layer of concrete grade M – 10 (1:3: 6) shall be laid immediately the excavation is carried down to foundation level. The blinding surface shall be thoroughly clean before foundation concrete is deposited there on. Sumps shall be provided where necessary to facilitate the control of drained water. The grade shall be applied as follows:


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Grades of Blinding Location Grade Thickness of layer

Foundation and bases M-10 75mm. Floors and ducts, trough and reinforced slabs not exceeding 100mm.

M-10 50mm.

24.28. Design 24.28.1. All foundations shall be of reinforced cement concrete. The design and construction of RCC structures shall be carried out as per IS : 456 and minimum grade of concrete shall be M-15 corresponding to 1:2:4 nominal mix ratio with 20mm. coarse aggregate. However minimum cement content shall be kept at 310kg. per cubic meter of concrete than specified above may be used at the discretion of the Bidder which has to be stated at the time of bidding. 24.28.2. Limit state method of design shall be adopted unless specified otherwise in the specification. 24.28.3. For design and construction of steel concrete composite beam IS: 11384 shall be followed. 24.28.4. For detailing of reinforcement IS: 2502 shall be followed. Cold twisted deform bars (Fe=415N/mm ²) conforming to IS 1786 shall be used as reinforcement. However in specific areas, mild steel (Grade 1) conforming to IS : 432 can also be used. Two layers reinforcement (on inner and outer face) shall be provided for wall and slab section having thickness of 150mm. and above. Clean cover to reinforcement towards the earth face shall be a minimum 40mm. 24.28.5. The procedure used for the design of the foundations shall be the most critical loading combination of the steel structure and or equipment and / or super structure and other conditions which produces the maximum stresses in the foundations or the foundation component and as per the relevant IS codes for foundation design. Detail design calculation shall be submitted by the Contractor. All the work (design and testing) shall be planned in such a way that these shall not cause any delay in project completion. 24.28.6. All foundation shall rest below virgin ground level and the minimum depth of foundation below the virgin ground level shall be at lest 500mm. for equipment foundations and 1000mm. for towers and columns. 24.28.7. Design shall consider any sub soil water pressure that may be encountered, following the relevant standard strictly. 24.28.8. Necessary protection to the foundation work, if required, shall be provided to take care of any special requirements for aggressive alkaline soil, black cotton soil or any other type of soil which is detrimental to the concrete foundation. 24.28.9. RCC columns shall be provided with rigid connection at the base. 24.28.10. All building sub-structures shall be checked for sliding and over turning stability during both construction and operating conditions for various combinations of loads. Factors of safety for these cases shall be taken as mentioned in relevant IS: Codes or as stipulated else where in the specifications. 24.28.11. Earth pressure for all underground structure shall be calculated using co-efficient for earth pressure at rest, co-efficient of active or passive earth pressure (which ever is applicable).


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However for the design of substructure of any underground enclosures, earth pressure at rest shall be considered. 24.28.12. In additional to earth pressure and ground water pressure etc., a surcharge load of two tones/ m ² shall also be considered for the design of all under ground structures including channels, sumps, tanks, trenches, sub-structures of any under ground hollow enclosures etc. for the vehicular traffic in the vicinity of the structure. 24.28.13. The following conditions shall be considered for the design of water tank in pump house, channels, sumps, trenches and other underground structures. a) Full water pressure from inside without earth pressure, ground water pressure or surcharge pressure from out side (applicable only to structures which are liable to be filled up with water or any other liquid).

b) Full earth pressure, surcharge pressure and ground water pressure from out side & no water pressure from inside.

c) Design shall also be checked against buoyancy due to the ground water during construction and maintenance stages, minimum factor of safety of 1.5 against buoyancy shall be ensured ignoring the supper-imposed loadings.

24.28.14. The base slab of any underground enclosure shall be design for empty condition during construction and maintenance stages with maximum ground water table (GWT). Minimum factor of safety of 1.5 against buoyancy shall be ensured ignoring the supper imposed loadings.

24.28.15. Base slab of any underground enclosure like water storage tank shall also be designed for the condition of different combinations of pump sumps being empty during maintenance stages with maximum (GWT). Inter mediate dividing piers of such enclosure shall be designed considering water in one pump sump only and the other pump sump being empty for maintenance.

24.28.16. The foundations shall be proportioned so that the estimated total and differential movements of the foundations are not greater than the movements that the structure or equipment is designed to accommodate.

24.28.17. Other foundations: All foundations shall be designed in accordance with the provisions of the relevant parts of latest revisions of Indian Standards IS: 2911 and IS: 456

24.28.18. The gantry/ tower foundations shall be designed for an additional factor of safety of 1.1 for normal broken wire conditions and for short circuit conditions.

24.28.19. The CB foundation shall be designed for impact loading and shall be in accordance with the manufactur’s recommendations.

24.29. Admixtures and Additives.

Only approved admixtures shall be used in the concrete for the works. When more than one admixture is to be used, each admixture shall be batched in its own batch and added to the mixing water separately before discharging into the mixer. Admixtures shall be delivered in suitably labeled containers to enable identification.

Admixtures in concrete shall conform to IS: 9103 the water proofing cement additives shall conform to

IS: 2645. Concrete Admixtures / Additives shall be approved by the S.E. (PLANNING and WORKS). The Contractor may propose and the S.E. (PLANNING and WORKS) may approved the use of a water-reducing set-retarding admixture in some of the concrete. The use of such an admixture will not be approved to overcome problems associated with inadequate concrete plant capacity or improperly planned placing operations and shall


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only be approved as an aid overcoming unusual circumstances and placing conditions. The water reducing set-retarding admixture shall be an approved brand of lingo-sulphonate type admixture.

Waterproofing cement additive to be used shall be approved by the S.E. (PLANNING and WORKS).

25. LATTIC STEEL SUPPORT STRUCTURES

25.1. General

This section covers design, fabrication, assembly, supply and erection of Galvanized busbar / Gantry support

structures and equipment support structures where these are of lattice steel construction.

The scope shall include all types of bolts, nuts, hangers, shackles, clamps, anticlimbing devices, bird guards, inserts in concrete, gusset, plates, equipment mounting bolts, structures earthing bolts, foundations, spring washers, fixing plates, angles and bolts for structure mounted or ground mounted marshaling boxes (AC/DC marshaling boxes and equipment control cabinets) and any other items as required to complete the job. The connection of all structures to their foundations shall be by base plates and embedded anchor/foundationbolts. All steel structures and anchor/foundations bolts shall be fully hot dip galvanized. The weight of the zinc coating shall be at least 0.8Kg. /m² for anchor /foundation bolts and 0.61Kg./m² for structural members. One additional nut shall be provided below the base plate which may be used for the purpose of leveling. 25.2. Design requirements. Design and fabrication shall be as per provisions of IS: 802 and IS: 800 for provisions not given in IS: 802 and other relevant IS standards. The Contractor may use IS 802 part 1 (1977) or IS: 802 part 1 (1995) for the design of the structures. The stsndard which is proposed to be used shall be stated in the bid. The installation shall be in accordance with the Indian standard code of IS: 802 and as follows. Minimum thickness of Galvanized tower member shall be as follows: Minimum Thickness (mm.)

Leg members, Ground wire peak Members/main members. 6 Other members 5 Redundant members 4

Maximum slenderness ratios for leg members, other stressed members and redundant members for compression force shall be as per IS – 802. Minimum distance from hole center to edge shall be 1.5 x bolt diameter. Minimum distance between center to center of holes shall be 2.5xbolt diameter. The minimum bolt diameter shall be 16mm. All structures shall be designed for the worst combinations of dead loads, live loads, wind loads as per code IS: 802, loads due to deviation of conductor, load due to unbalanced tension in conductor, torsional load due to


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unbalanced vertical and horizontal forces, erection loads and short circuit forces. Short circuit forces shall be calculated considering a fault level of 25KA for 33KV and 12.5KA for 11KV. IE – 865 and CIGRE guide number 7 may be followed to estimate the various forces of conductor for structural design. • Busbar/Gantry lattice structures shall be designed as per code IS 802 for the three conditions i.e. normal

conditions, three conductors on one side broken and broken wire conditions and short circuit force. The design of all structure shall be based on the conditions where stringing is done only on one side i.e. the conductors of all three phases broken on the other side.

• If designing to code IS:802 part 1 (1977), a factor of safety of 2.0 under normal as well as broken wire conditions and 1.5 under combined short circuit and broken wire conditions shall be considered for the design of switchyard structures. For purpose of design 110% of static tension pull and transverse reaction on the gantries as calculated for each span shall be considered.

• A vertical load of half the span of conductors/string and the earth wires on either side of the beam shall be taken into account for the purpose of design. However, in the case of the overhead line terminating span the vertical load of the total download span shall be taken into account. The weight of a man with tools shall be considered as 150kg. for the design of structures.

• Gantry/busbar structures shall be designed for appropriate conductor tension of the download spans from the line terminal structures of 33KV and 11KV lines.

• The girders shall be connected with lattice columns by bolted joints. • If luminaries are proposed to be fixed on gantries/towers, then the proper loading for the same shall be

considered while designing. Also holes for fixing the brackets for luminaries should be provided wherever required.

25.3. Fabrication of steel The fabrication and erection works shall be carried out generally in accordance with IS 802. A reference however may be made to IS 800, in case of non-stipulation of some particular provision in IS 802. Before leaving the manufacturer’s works all members shall be hard stamped in approved positions with distinguishing numbers and/or letters corresponding to distinguishing numbers and / or letters on approved drawings or materials list to be submitted by the contractor. All materials shall be completely shop fabricated and supplied with proper fixing materials for ready assembly in the field. 25.4. Assembly 25.4.1. General The component part shall be assembled in such a manner that they are neither twisted nor otherwise damaged and shall be so prepared that the specified camber, if any, is provided. The structure members shall be accurately fabricated so as to bolt easily together at site without any undue strain to other structure members, bolts or the structure itself in any part, otherwise the structure shall be rejected. Sample towers and beams shall be trial assembled keeping in view the actual site conditions, before erection in the fabrication shop and shall be inspected and approved by S.E. (PLANNING and WORKS) before mass fabrication. Necessary matching marks shall be made on these components in the shop before disassembly and dispatching. 25.4.2. Bolting Every bolt shall be provided with a washer under the nut so that part of the threaded portion of the bolt is within the thickness of the parts bolted together.

• All steel items, bolts, nuts and washers shall be hot dip galvanized • 2.0% extra nuts and bolts shall be supplied for erection


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25.4.3. Welding Lattice steel structures shall be of bolted construction. Unless otherwise specified, welding at any point shall not be permitted. 25.5. Stability of Structure The Contractor shall be responsible for the stability of the structure at all stages of its erection at site and shall take all necessary measures by the addition of temporary bracings and guying to ensure adequate resistance to wind and also to loads due to erection equipment and their operations. 25.6. Grouting The column bases shall be grouted, using a mix of one part of cement and two part of coarse sand. The method of grouting shall be subject to approval of S.E. (PLANNING and WORKS), Head of the APDRP and shall be such as to ensure a complete uniformity of contact over the whole area of the steel base. The Contractor will be fully responsible for the grouting operations. No shrinkage admixtures of approved quality and standard make shall also be added in adequate proportion as specified by the manufactur’s of the admixtures. 25.7. Testing and inspection The contractor shall give full access to the S.E. (PLANNING and WORKS) at all times to the place of fabrication and storage for the purpose of inspection and testing. Copies of all test certificates relating to material procured by the Contractor for the works shall be forwarded to the S.E. (PLANNING and WORKS). When so instructed by the S.E. (PLANNING and WORKS), the Contractor shall provide samples of the steel to be used in the works for tests to be carried out at an independent laboratory approved by the S.E. (PLANNING and WORKS). The cost of these independent tests shall be paid for by the Contractor. Should the works or any part thereof fail to pass any test or in the opinion of the S.E. (PLANNING and WORKS), fail to comply with the specification, the Contractor shall immediately take such action as is necessary to ensure that the works comply with the specification. All defective material and workmanship will be rejected and shall be replaced and reconstructed at the Contractor’s expense. No splice welding of members between connections shall be permitted without the prior approval of the S.E. (PLANNING and WORKS). 25.8. Erection The Contractor should arrange his own erection plant and equipment, tools and tackles, scaffolding, trestles equipment and any other accessories and ancillaries required for the work. Finished structures shall be plumb, level and true to dimensions, within the tolerance specified. 25.9. Protection of Steel and ironwork generally All steel and ironwork specified to be galvanized shall be fabricated before galvanizing. Site drilling or cutting of steel will generally not be permitted, but any agreed to be necessary shall be carried out in an approved fashion and the exposed bare metal treated immediately with zinc rich or other approved metallic primer as approved or directed by the S.E. (PLANNING and WORKS), Head of the APDRP.


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25.10. Safety Precautions The Contractor shall strictly follow at all stages of fabrication, transportation and erection of steel structures, raw materials and other tools and tackles, the stipulations contained in Indian Standard Code for erection for structural steel work IS: 7205. 26. SUBSTATION EARTHING 26.1. General requirements The earth mat system, together with all earth connections shall be designed and installed by the Contractor in accordance with the recommendations contained in IS 3043 – code of practice for earthing (1991). Each earth mat system shall consist of a grid of 50mm. x 6mm. galvanized iron flat Conductor strips at 600mm. minimum depth with mesh size designed to limit touch and step voltages to safe values as recommended in IS 3043. If safe values of touch and step voltages cannot be achieved by a Conductor grid alone, pipe or rod earthing shall be added as necessary. In designing the earth electrode system the following levels of earth fault currents shall be used: 11KV 12.5KA 3s 33KV 25KA 3s The resistance of the earth electrode system shall not exceed 1.0 ohm. An allowance shall be made for the progressive reduction of the cross sectional area of buried earth conductors by 30% due to chemical action. On completion of each installation, the earth resistance shall be measured and the results recorded. The test methods shall be subjected to the approval of the S.E. (PLANNING and WORKS), who will arrange to have the tests witnessed. In the event of the set limits being exceeded the Contractor shall modify the earthing system at his expense to attain values within the specified limits. 26.2. Earth Conductors All buried earth conductors and all connections to the buried earth grid shall be made of 50mm. x 6mm. G.I. strip. All the metallic non current carrying parts of substation equipment and Steel work shall be connected by two independent earth strips to the earth grid. This requirement shall not apply where earth would be impractical, e.g. metal door handles on wooden doors. The following guidelines shall be used when installing the earth mesh: • All the joints of the grounding G.I. strips between themselves and earth electrodes shall be overlap welded.

The length of the weld shall be double the width of the strip; • Before welding the strips should be clamped tightly to ensure good surface contact between them; • Welded joints in earth strip shall be treated with anticorrosive paint. In addition, Joints located in soil shall be

covered with bitumen impregnated tape;


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• Trenches dug for laying of earth conductor shall be filled with soil free from stone and the filling shall be carefully compacted;

• The 11KV neutral point of each transformer shall be earthed by means of two separate earth conductors each brought to an independent pipe or rod electrode. The electrodes shall be connected together and shall also be connected to the earth grid at two points;

• The earth lead of out door surge arresters shall be direct run of fully rated conductor from the arrester earth terminal to a pipe or rod electrode. At each location the rods associated with the three phase arresters shall be connected together and shall also be connected to the earth grid system at two points. In order to achieve minimum surge impedance the earth conductor shall be kept as short and free from bends as possible. The Conductor shall be fastened to its supporting surface in order to withstand any electrodynamic forces and shall be protected against mechanical damage.

• Cable sheaths shall be bonded to earth by means of one fully rated conductor in accordance with the requirements of the cable manufacture.

• Exposed earth conductor shall be inconspicuously installed in vertical or horizontal formation and shall be neatly fastened to supporting surfaces.

• Connections to the earth terminals of equipment and structures shall be made using a bolted connection. • Suitably sized PVC tubes shall be grouted in during the construction of the building to facilitate leading earth

Conductors through walls and floors. 26.3. Earth electrodes Earth electrodes shall be galvanized steel rods of 20mm. diameter and 2.5meters in length or galvanized iron pipes of 40mm. diameter and 2.5meters in length. If it is necessary to form extended length of rod to achieve safe values of touch and step voltages, suitable approved coupling methods shall be used. All materials, methods of coupling and driving heads shall be suitable for driving with a power hammer and shall be to the approval of the Employer. The earth electrodes shall be in accordance with IS 3043. in locations where water strata cannot be reached, artificial earth pit shall be made using salt and charcoal of sufficient quantity. 26.4. Maintenance earthing points If it is necessary to connect normally live parts to earth for maintenance purposes by means of temporary flexible earth leads, fixed earthing points shall be provided close to the equipment. Such earthing points shall be connected to the earth electrode system by means of a fully rated earth conductor. 26.5. Extension of existing earth electrode system Where an existing station is to be extended, the new earth electrode system shall be connected to the existing earth electrode system by at least four 50mm. x 6mm. GI. Flat conductors. The Contractor shall ensure that touch and step voltage are maintained within recommended safe limits. 26.6. Drawings and information The following drawings and information shall be submitted as part of the bid:

• Typical layout of the proposed earth electrode system: and • Drawings and information describing the various types of connectors and joints.


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The following drawings and information shall be submitted to the S.E. (PLANNING and WORKS), Head of the APDRP, within three months of the date of contract award:

• Final layout drawings of the earthing system for each substation; • Earthing system, design calculations encompassing measured date from soil receptivity tests, receptivity

curves and earthing electrode resistances; • Detailed specifications and descriptions of all materials used; and • Detailed specifications and descriptions of installation and jointing methods including details of special

tools used. 27. SITE TESTING, INSPECTION, PRE-COMMISSIONNING AND COMMISSIONING The Contractor within one month of contract award shall submit detailed proposals and a programme for the site measurements, inspection and testing of all substation plant and equipment to the S.E. (PLANNING and WORKS), for approval. The proposals shall include for detailed testing, pre-commissioning and commissioning reports for the substation and for the installed equipment, including but not be limited the following:

• Power Transformers; • Isolators; • Voltage transformers; • Surge arresters; • Control, protection, annunciation and metering system; • Busbars and connections to equipment; • 33/11KV Power transformers with associated remote on load change control panels; • 33KV and 11KV outdoor circuit breakers with associated CTs; • 11KV Automatic recloser; • 11KV indoor matelclad switchboard; • Power and Control Cables; • ACDC System;

AC Distribution Boards; DC Distribution Boards; Battery and Battery Charger; Auxiliary transformers (both 33/.433 and 11/.433KV)

• Structures for; Switchyard gantries/portals; Equipment;

• Earth mat and associated earth connection materials;

The S.E. (PLANNING and WORKS), may arranged to have these tests witnessed. In order to facilitate this, the contractor shall give the S.E. (PLANNING and WORKS), a minimum of four weeks notice that the equipment is ready for testing. If the S.E. (PLANNING and WORKS), dose not indicate his intention to participate in the testing, the manufacturer may proceed with the tests and shall furnish the results thereof to the S.E. (PLANNING and WORKS). All equipment and materials necessary for testing and inspection shall be supplied by the Contractor. Test result shall be submitted to the S.E. (PLANNING and WORKS) and commissioning of the equipment shall be carried out after receipt of approval from him. Payment of statutory inspection fees and filing of papers for such inspection shall be done by the Contractor.


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28. FIRE EXTINGUISHERS For each 33/11KV transformer a dry powder fire extinguisher of not less than 9Kg. Capacity, mounted in a suitable weatherproof box shall be provided adjacent to the transformer. The dry powder extinguishers shall conform to IS 2171. Two CO2 fire extinguishers each of not less than 5Kg. Capacity shall be wall mounted in convenient locations in the control room in substation. The CO2 fire extinguishers shall conform to IS: 2878. PART 3 GENERAL PARTICULARS AND GUARANTEES 29. OPERATIONAL TRAINING Contractor shall provide comprehensive training to the employer staff for each new 33/11KV Primary substation constructed under the contract. The contractor shall provide the instructor and all documentation for the training of upto ten of the employer staff. At each substation the training shall be completed before the substation is handed over. The training shall include but not be limited to the following: • Operations of all isolators, circuit breakers, auto reclosers, other switches, transformers and on load tap

changers. Remote and local operation and inter locking facilities will be included as required. • Operation, resetting, testing and performance of metering, annouanciation and protection schemes, including

relays, alarms, indicators and other associated equipment. • Response to the various automatic operation and alarm conditions which could arise in the substation. • Operation and monitoring of substation battery and other substation equipment. • Routine preventive maintenance of equipment including lubrication, operational testing, monitoring, topping

up of dielectric and electrolyte as required. The Contractor shall add to the above other items for which it is appropriate to provide instruction. The substation and manufacturer’s operation and maintenance manuals shall be the basis for the training materials. The training will mainly be hands on and all staff attending the training shall perform the various operations under the direction of the instructor. All training course notes and documentation shall be in the English language. Training shall generally be conducted in English, however the Contractor shall ensure that provision is made for on the spot interpretation to the location language (ORIYA) to ensure complete understanding. The Contractor shall submit detailted proposals for the training courses within 90days of the effective date of contract. These proposals shall include the relevant experience of the instructor and the draft training documentation. The training proposals and documentation shall be subject to the approval of the S.E. (PLANNING and WORKS), the cost of training shall be included in the overall cost of the facilities. 30. COMPLIANCE WITH SPECIFICATION The equipment shall comply in all respect with the requirements of this specification. However any minor departure from the provision of the specification shall be disclosed at the time of bidding in the non-compliance schedule either in this document or the appropriate technical specification. The mass and dimensions of any item of equipment shall not exceed the figures stated in the schedules.


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31. COMPLIANCE WITH REGULATIONS All the equipment shall comply in all respects with the Indian regulations and acts in force. The equipment and connections shall be designed and arrange to minimize the risk of fire and any damage which might be caused in the event of fire. 32. QUALITY ASSURANCE, INSPECTION and TESTING 32.1. General To ensure that the supply and services under the scope of this contract, whether manufactured or perform within the contractor’s works or at his sub-contractors premises or at any other place of work or in accordance with the specification, with the regulations and with relevant authorized International or Indian standards, the Contractor shall adopt suitable quality assurance programmes and procedures to ensure that all activities are being controlled as necessary. The quality assurance arrangements shall conform to the relevant requirements of ISO: 9001 or ISO: 9002 as appropriate. The systems and procedures which the Contractor will use to ensure that the plant complies with the contract requirements shall be defined in the Contractor’s quality plan for the works. The Contractor shall operate systems which implement the following: Hold Point “A stage in the material procurement or workmanship process beyond which work shall not proceed without the documented approval of designated individuals or organizations”. The S.E. (PLANNING and WORKS), written approval is required to authorize work to progress beyond the Hold Points indicated in approval quality plans. Notification point “A stage in material procurement or workmanship process for which advance notice of the activities is required to facilitate witness”. If the S.E. (PLANNING and WORKS), does not attend after receiving documented notification in accordance with the agreed procedures and with the correct period of notice then work may proceed. 32.2. Quality assurance program Unless the Contractors quality assurance system has been audited and approved by S.E. (PLANNING and WORKS), a quality assurance program for the works shall be submitted to S.E. (PLANNING and WORKS), for approval a minimum of one month from contract award, or such other period as shall be agreed with the S.E. (PLANNING and WORKS). The quality assurance program shall give a description of the quality system for the works and shall, unless advised otherwise, include details of the following:

• The structure of the Organization. • The duties and responsibilities assigned to staff ensuring quality of work. • The system for purchasing, taking delivery and verification of materials. • The system for ensuring quality of workmanship. • The system for control of documentation. • The system for the retention of records.


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• The arrangements for the Contractors internal auditing. The list of the administration and work procedures required to achieve and verify Contractor’s quality requirements. These procedures shall be made readily available to the S.E. (PLANNING and WORKS), Head of the APDRP for inspection on request.

32.3. Quality Plans The Contractor shall draw up for each erection of the work quality plans which shall be submitted to the S.E. (PLANNING and WORKS), for approval at least two weeks prior to the commencement of work on the particular section. Each quality plan shall set out the activities in a logical sequences and unless advised otherwise shall include the following:

• An out line of the proposed work and programme sequence: • The structure of the Contractor’s Organization for the contract; • The duties and responsibilities and responsibilities assigned to ensuring quality of work for the contract; • Hold and notification point; • Submission of Engineering documents required by the specification; • The inspection of materials and components on receipt; • Reference to the Contractor’s work procedures appropriate to each activity; • Inspection during fabrication/Construction; • Final inspection and test;

32.4. Non-conforming product The S.E. (PLANNING and WORKS) shall retain responsibility for decisions regarding acceptance, modification or rejection of non-conforming items. 32.5. Sub-Contractors The Contractor shall ensure that the Quality Assurance requirements of this specification are followed by any Sub-Contractors appointed by him under the Contract. The Contractor shall assess the Sub-Contractor’s Quality Assurance arrangements prior to his appointment to ensure compliance with the appropriate ISO 9000 standard and the specification. Auditing of the Sub-Contractor’s Quality Assurance arrangements shall be carried out by the Contractor and recorded in such a manner that demonstrates to the S.E. (PLANNING and WORKS) the extent of the audits and their effectiveness. 32.6. Inspection and testing The S.E. (PLANNING and WORKS) shall have free entry at all times, while work on the contract is being performed to all parts of the manufacturers works which concern the processing of the equipment ordered. The manufacturer shall afford the S.E. (PLANNING and WORKS) with out charge, all responsible facilities to assure that the equipment being furnished is in accordance with this specification. The equipment shall successfully pass all the type test and routine test referred to in the individual technical specifications and those listed in the most recent addition of the standards given in this specification. The S.E. (PLANNING and WORKS), reserves the right to reject an item of equipment if the test results do not comply with the values specified or with the data given in the technical data schedule.


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Type test shall be carried out at an independent testing laboratory or be witnessed by representative of such laboratory or some other representative acceptable to the S.E. (PLANNING and WORKS). Routine and acceptance test shall be carried out by the Contractor at no extra charge at the manufacturer’s works. Type test certificate shall be submitted with the bid for evaluation. The requirement for additional type tests will be at the discretion of the S.E. (PLANNING and WORKS). The S.E. (PLANNING and WORKS), may witness routine and type test. In order to facilitate this, the Contractor shall give the S.E. (PLANNING and WORKS) a minimum of four weeks notice that the material is ready for testing. If the S.E. (PLANNING and WORKS) does not indicate his intention to participate in the testing, the manufacturer may proceed with the test and shall furnish the results thereof to the S.E. (PLANNING and WORKS). Full details of the proposed methods of testing, including connection diagrams shall be submitted to the S.E. (PLANNING and WORKS) by the Contractor for approval at least one month before testing. All costs in connection with the testing, including any necessary re-testing, shall be borne by the Contractor, who shall provide the S.E. (PLANNING and WORKS) with all the facilities which the latter may require, free of charge. The S.E. (PLANNING and WORKS) shall have the right to select the samples for test and shall also have the right to assure that the testing apparatus is correct. Measuring apparatus for routine test shall be calibrated at the expense of the Contractor at an approved laboratory and shall be approved by the S.E. (PLANNING and WORKS). The Contractor shall be responsible for the proper testing of the plant or materials supplied by Sub-Contractors to the same extent as if the plant or materials were completed or supplied by the Contractor. Any cost incurred by the S.E. (PLANNING and WORKS) in connection with inspection and retesting as a result of failure of the equipment under test or damage during transport or off-loading shall be to the account of the Contractor. The Contractor shall submit to the S.E. (PLANNING and WORKS) five signed copies of the test certificates, giving the results of the test as required. No materials shall be dispatched until the test certificates have been received by the S.E. (PLANNING and WORKS) and the contractor has been informed that they are acceptable. The test certificate must show the actual values obtained from the tests, in the units used in this specifications and not merely conform that the requirements have been met. In the case of component for which specific type test or routine test are not given in this specifications. The Contractor shall include a list of the tests normally required for these components. All materials used in the contract shall with stand and shall be certified to have satisfactorily passed such test. No inspection or lack of inspection or passing by the S.E. (PLANNING and WORKS) or his representative, of equipment or materials whether supplied by the Contractor or Sub-Contractor shall relieve the Contractor from his liability to complete the Contract works in accordance with the Contract or exonerate him from any of his guarantees. 32.7. Guarantee The Contractor shall guarantee the following:

• Quality and strength of materials used:


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• Satisfactory operation during the guarantee period of one year from the date of commissioning, or 18 months from the date of acceptance of the equipment by the S.E. (PLANNING and WORKS) following delivery, whichever is the earlier:

• Performance figures as supplied by the bidder in the technical data schedules. • The offered surface treatment shall protect the treated metal from corrosion for a period of not less than

five years from the date of delivery. 33. PROGRESS REPORTING The Contractor shall submit for approval within four weeks of the effectives date of contract, and line of production, inspection, delivery, erection, pre-commissioning and commissioning in chart form. Within a further period of four weeks, the Contractor shall provide a detailed program of the same information in a form to be agreed by the S.E. (PLANNING and WORKS).The Contractor shall submit two copies of monthly progress reports not later than the seventh day of the following month. The report shall show clearly and accurately the position of all activities associated with the material procurement, manufacture, work tests and transport, with regard to the agreed contract program. The format for presentation of programs is M/s Project version 4.0 programs and monthly up dates should be submitted on 3.5 diskettes. The design aspect of the progress report shall include a comprehensive statement on drawings, Calculation and type test reports submitted for approval. The position on material procurement shall give the details of orders placed and indicate the delivery dates quoted by the manufacturer. If any delivery date has an adverse effect on the contract programme, the Contractor shall state the remedial action taken to ensure that delays do not occur. The position on manufacturer shall indicate the arrival of raw material and the progress of manufacture. Any events that may adversely effect completion in the manufacturer’s works shall also be reported. All works test done shall be listed and test results shall be remarked upon. Any test failure shall be highlighted. The dispatch of each order shall be monitored on the progress report giving the date by which the equipment will be available for transport, the estimated time of arrival on site and the dates actually achieved. Delays or test failures in any part of the programme which may affect any milestone or final completion dates shall be detailed by the Contractor who shall state the action taken to effect contract completion in accordance with the contract programme. 34. SPARE PARTS AND SPECIAL TOOLS The Contractor shall provide the mandatory spares as detailed in the schedules and the individual technical specification. The prices of mandatory spares will be taken in to account in the evaluation of bids. The bidder shall provide a list of recommended spare parts together with their individual prices. This list shall identify all essential spare items for any recommended maintenance for a period of five years after commissioning. The S.E. (PLANNING and WORKS) may order all or any of the spare parts listed at the time of contract award and the spare parts so ordered shall be supplied as part of the definite works. The S.E. (PLANNING and


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WORKS), may order additional spares at any time during the contract period at the rates stated in the contract document. A spare parts catalogue with price list shall be provided and this shall form part of the drawings & literature to be supplied. The Bidder shall give an assurance that spare parts and consumable items will continue to be available through the life of the equipment, which shall be 25 years minimum. However the Contractor shall give a minimum of 12 months notice in event that the contractor or any sub-contractor plan to discontinue manufacture of any component used in this equipment. Any spare apparatus, parts or tools shall be subject to the same specification, test and conditions as similar material supplied under the contract. They shall be strictly interchangeable and suitable for use in place of the corresponding parts supplied with the plant and must be suitably marked and numbered for identification. Spare parts shall be delivered suitably packed and treated for long periods in storage, each pack shall be clearly and indelibly marked with its contents, including a designation number corresponding to the spare parts list in the operation and maintenance instructions. A complete set of all the special tools, devices, slings or tackles required for the adjustment and maintenance of the equipment shall be supplied in the quantity listed in the schedule. Each set of tools shall be mounted in a lockable cabinet. Eye bolts which have to be removed after use shall be accommodated in the cabinet. Spanner and other maintenance equipment provided under this contract shall not be used for the purpose of erection of the equipment. Any special devices, slings or shackles necessary for the maintenance of equipment shall be handed over to the employer in working order on completion of the installation and commissioning of the substation. 34.1. Operation and maintenance 34.1.1. Operation handles Operation handles or operation rods required for manual operation shall be mounted in the controll building and shall be appropriately labeled. Operating handles and operating rods shall be supplied and priced as part of the equipment and not as separate items. 34.1.2. Portable earth equipment Each substation shall be provided with one set of portable earthing equipment for all open type equipment. The Contractor shall provide for the neat storage of portable earthing equipment in each substation. 34.1.3. Storage Lockable storage shall be provided in each station for operating handles, operating rods, portable earth, tools and all other loose equipment. 34.1.4. Key Box A lockable key box shall be provided in each station, for the storage of all equipment keys and operating handle keys. Key box shall be supplied as part of the building and shall not be separately priced.


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35. PACKING AND SHIPPING 35.1. Packing The equipment and any supporting structures are to be transported adequately sealed against water ingress. All accessories and spares shall be packed and securely clamped against movement in robust wooden, non-returnable packing cases to ensure safe transit in rough terrain, cross country road conditions and in heavy rain from the manufacturer’s works to the work sites. Equipment or material liable for deterioration by sea water, moisture or ingress of foreign matter shall be totally sealed in strong polythene bags and those liable to deterioration due to condensation shall be protected by packs of silica gel or other approved desiccant. All accessories shall be carefully packed so that they are fully protected during transport and handling operations and in storage. Internal surfaces of loose accessories shall be sealed by means of gaskets and bcanking off plates. All parts liable to rust shall receive an anti-rusting coat and shall be suitably protected. It shall be the responsibility of the contractor to make good any damage caused through insufficient packing. Each packing case shall be indelibly marked on two adjacent sides and on the top with the following:

• Individual serial number; • Employer’s name; • Contract number • Destination; • A color coded marking to indicate destination; • Contractor’s name; • Name and address of Contractor’s agent in Orissa; • Description and number of contents; • Manufacturer’s name; • Country of origin; • Case measurements; • Gross and Net weights in kilo Grams; and • All necessary slinging and stacking instructions;

Each crate or container shall be marked clearly on the out side of the case to show TOP and BOTTOM positions with appropriate signs to indicate where the mass is bearing and the correct positions for slings. All components parts which are separately transported shall have permanent identifications marks to facilitate coreect matching and assembly at site. Welded parts shall be marked before welding. Six copies of each packing list shall be sent to the S.E. (PLANNING and WORKS), prior to dispatching the equipment. 35.2. Shipping The Contractor shall be responsible for the shipping of all plant and equipment supplied from abroad to the ports of entry and for the transport of all goods to the various specified destinations including customs clearance, off-loading, warehousing and insurance. The contractor shall inform himself as to all relevant transport facilities and requirements and loading gauges and ensure that the equipment as packed for transport shall conform to these limitations.


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The Contractor shall also be responsible for verifying the access facilities specified. The contractor shall be responsible for the transportation of all loads associated with the contract works and shall take all reasonable steps to prevent any high ways or bridges from being damaged by his traffic and shall select routes. Choose and use vehicles and restrict and distribute loads so that the risk of damage shall be avoided. The contractor shall immediately report to the S.E. (PLANNING and WORKS), Head of the APDRP, any claims made against the contractor arising out of alleged damage to a high way or bridge. All transport accessories such as riding lugs, jacking pads or blanking off plates shall become the property of the employer. All items of equipment shall be securely clamped against movement to ensure safe transit for the manufacturer’s facilities to the appropriate depot or work sites. The contractor shall advise the storage requirements for any plant and equipment that may be delivered to the S.E. (PLANNING and WORKS). The contractor shall be required to accept responsibilities for the advice given in so far as these arrangements may have a bearing on the behavior of the equipment in subsequent service. 35.3. Hazardous substances The Contractor shall submit safety data sheet in a form to be agreed for all hazardous substances used with the equipment. The Contractor shall give an assurance that there are no other substances classified as hazardous in the equipment supplied. No oil shall be supplied or used at any stage of manufacture or test without a certificate acceptable to the S.E. (PLANNING and WORKS) that it has a PCB content of less than 2mg./Kg. the Contractor shall accept responsibility for the disposal of such hazardous substances, should any be found. The Contractor shall be responsible for any injuries resulting from hazardous substances due to non-compliance with these requirements. 36. SUBMITTALS 36.1. Submittals required with the bid The following shall be required in duplicate:

• Completed technical data schedules; • Descriptive literature giving full technical details of equipment offered; • Layout drawings for substation depicting the proposed arrangement of switchyard, fencing, outdoor

equipment and control/switch room building; • Layout drawings substation control buildings showing proposed arrangement of switchboard, control

panels, battery charger, AC and DC distribution boards; • Outline dimension drawing for equipment and for each component, general arrangement, drawing

showing component layout and general schematic diagrams; • Type test certificates, where available and sample routine test reports; • Detailed reference list of customers already using equipment offered during the last 5years with particular

emphasis on units of similar design and rating; • Outline quality plan including a method statement and program for the execution of the works; • Details of manufacturer’s quality assurance standards & programme and ISO 9000 series or equivalent

national certification; • Deviations from this specification. Only deviations approved in writing before award of contract shall be

accepted;


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• List of recommended spare parts for five years of operation with prices and spare parts catalogue with price list for future requirements.

36.2. Submittals required after contract award 36.2.1. Programme • Within 30days of the effective date of Contract, the Contractor shall provide five copies of an outline

programme of production, inspection, testing, delivery, survey, erection, precommissioning and commissioning in chart form. Included in the programme will be the detailed schedule of drawing to be submitted.

• Within 60days of the effective date of contract, the Contractor shall provide five hard copies of a detailed programme of the same information in a form to be agreed by the S.E. (PLANNING and WORKS). One copy of the programme on 3.5” diskette, shall also be provided.

• Each month from the effective date of contract, the contractor shall submit three hard copies of monthly progress reports not later than the seventh day of the following month. One copy shall also be provided on 3.5” diskette.

The format for presentation of programmers is MS Project version 4.0. The programmes and monthly updates shall be submitted on 3.5” floppy diskettes. The design aspect of the progress report shall include a comprehensive state on drawing and calculations submitted for approval. The position on material procurement shall give the date and details of order placed and indicate the test date and delivery date quoted by the manufacturer. If any delivery date has an adverse affect on the contract programme the Contractor shall state the remedial action taken to ensure that delays do not occur. The position on manufacturer shall indicate the arrival of material, the progress of manufacture and date at which the equipment will be ready for test and transport. Any events that may adversely affect completion in the manufacturer’s work shall also be reported. All works tested executed shall be listed and the test results shall be remarked upon. Any test failure shall be highlighted and the Contractor shall detail the necessary steps taken in order to avoid any adverse effect on the contract completion dates. The dispatch of each order shall be monitored on the progress report giving the date by which the equipment will be available for transport, the estimated time of arrival on site and the dates actually achieved. The site work shall be segregated in to civil, mechanical and electrical works for reporting purposes and each section of the site works shall be monitored giving the percentage completion and the estimated completion date in accordance with the contract program. The no. of man working on site, both labour and supervisory staff, shall be reported together with any incidence or events that may effect the progress of site works. Any delays which may effect any mile stone or final completion dates shall be detailed by the Contractor who shall state the action taken to effect contract completion in accordance with the contract program. 36.2.2. Technical Particulars. Within 60 days of effective date of contract award five bound folders with records of the technical particulars relating to the facilities. Each folder shall contain the following information:


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• General description of the equipment and all components including brochures; • Technical data schedule for all Contractor supplied equipment, with approved revisions; • Detailed layout drawing for substation showing control building, switch yard, fencing, gate and roads; • Drawing showing the arrangement of cable trenches for power and control cables; • Drawing showing plan and elevation of structures and equipment in the switch yard; • Statement drawing attention to all exposed points in the equipment at which copper, alluminium or aluminium

alloy parts are in contact with or in close proximity to other metals and stating clearly what protection is employed to prevent corrosion at point.

Within 90 days of effective date of contract award five bound folders with records of the technical particulars relating to the facilities. Each folder shall contain the following information; • Survey reports for substation sites; • Detailed list of price scheduled items and quantities to be included in each substations; • Calculations to substantiate choose of electrical structural, mechanical component size ratings; • Detailed dimension drawing for the equipment and for all component; • General arrangement drawing showing detailed component layout; • Detailed schematic and wiring drawings for all component; • Foundation design drawings and supporting calculation for columns, equipment support structures and

transformers; • Detailed layout drawing for the control building depicting ducts, trenches, switch board, panels and other

equipment in plan and elevation; • Drawing showing the layout and arrangement of the substation earth grid; • The installation and commissioning instructions; Note: The survey reports, price schedule item list, detailed designs and detailed programs for works shall be present at least nine months prior to the respective completion dates. At final hold point for S.E. (PLANNING and WORKS), approval prior to delivery of the equipment the following shall be submitted; • Inspection and test reports carried out in the manufacturer’s works; • Operation and maintenance instructions and trouble shooting charts for the equipment; 36.2.3. Operation and maintenance manuals For the 33/11 KV substations the contractor shall prepare a general operations and maintenance manual. When approved by the S.E. (PLANNING and WORKS), these manuals shall be the basis of the specific operations and maintenance manuals for each substation. The manuals shall be as complete and as specific as possible and shall in corporate documentation that is specific to the materials and equipment used on the contract. All precautions and warnings relating to the safety & life of equipment shall be included in the manuals. Six months before programme completion date of the first substation the following will be submitted for approval; • Three copies of the general operation and maintenance manuals; • Three copies of the training proposals and training documentation;


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After approval by the S.E. (PLANNING and WORKS), Head of the APDRP, the Contractor shall deliver ten copies of the complete manual. Two months before program completion date of each substation, three copies of the specification, installation and commissioning instructions and three copies of the specification, operation and maintenance manuals shall be supplied. The tacking over certificate will not be issued until the required number of approved copies of the manuals have been provided by the Contractor. 36.3. Drawings Within 30 days of the contract commencement the Contractor shall submit for approval by the S.E. (PLANNING and WORKS), a schedule of the drawings to be produced detailing which are to be submitted for “Approval” and which are to be submitted “For Information Only”. The schedule shall also provide a program of drawing submission, for approval by the S.E. (PLANNING and WORKS) that ensures that all drawings and calculations are submitted within the period specified above. All detail drawings submitted for approval shall be to scale not less than 1:20. all-important dimensions shall be given and the material of which each part is to be constructed shall be indicated on the drawings. All documents and drawings shall be submitted in accordance with the provisions of this specification and shall become the property of the Employer. All drawings and calculations submitted to the S.E. (PLANNING and WORKS) shall be on international standard size paper, A0, A1, A2, A3, or A4. All such drawings and calculations shall be provided with a contract title block, which shall include the name of the Employer and Consultants and shall be assigned a unique Project drawing number. The Contract title block and Project Numbering system shall be agreed with the S.E. (PLANNING and WORKS). Lettering size and thickness of lettering and lines shall be selected so that if reduce by two states to one quarter of their size, the alphanumeric characters and lines are still perfectly legible so as to enable them to be microfilmed. For presentation of design, drawing and circuit documents IEC publication 617 or equivalent standards for graphical symbols are to be followed. Details of the loads and fixing arrangements of the circuit breakers and transformers, supplied under a separate contract, shall be provided by the S.E. (PLANNING & WORKS), in order to enable the Contractor to design the foundations for these items of plant. All dimensions marked on drawings shall be considered contract although measurement by scale may differ from general arrangement drawings. Detailed drawings shall be worked to where they differ from general arrangement drawings. All documents, drawings and samples shall be submitted in accordance with the provisions of this specification and shall become the property of the employer. All drawings submitted by the Contractor shall be in sufficient detail to indicate the type, size, arrangement, material description, bill of materials, weight of each component, break-up for packing and shipment, the external connections, fixing arrangement and the dimensions , required for installation and interconnection with other equipment and materials, clearance and spaces required for installation and interconnection between various pertions of equipment and any other information specifically requested in the specification. Technical drawings must be shown, in a form understandable by the technicians, the information necessary to constract an installation or part of an installation. The drawings must therefore conform to following standards.


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36.4. Final as-built drawings After completion of work on site all drawings shall be revised where necessary to show the equipment as installed and three copies submitted duly signed by site-in-charge. Following approval, two reproducible transparencies and eight prints shall then be provided as required by the S.E. (PLANNING and WORKS), and shall of sufficient detail to enable all parts to be identified. The Contractor shall also submit where possible, digitally stored copies of all as built drawings on disc or CD-ROM in a format compatible with the employer’s drawing system. 37. APPROVAL PROCEDURE The Contractor shall submit all drawings; documents and type test reports for approval in sufficient time to permit modifications to be made if such are deemed necessary and resubmit them for approval without delaying the initial deliveries or completion of the contract work. The S.E. (PLANNING and WORKS), or his representative shall endeavor to return them within a period of four weeks from the date of receipt. Three copies of all drawings shall be submitted for approval and three copies for any subsequent revision. The S.E. (PLANNING and WORKS), reserves the right to request any further additional information that may be considered necessary in order to fully review the drawings. If the S.E. (PLANNING and WORKS), is satisfied with the drawing, one copy will be returned to the contractor marked with “Approved” stamps. If the S.E. (PLANNING and WORKS), is not totally satisfied with the drawing, then approved subject to comment status will be given to it and a comment sheet will be sent to the Contractor. If the drawing submitted dose not comply with the requirements of the specification then it will be given “Not Approved” status and a comment sheet will be sent to the Contractor. In both these cases the Contractor will have to modify the drawing, up date the revision column and submit for final Approval. Following approval, twenty copies of the final drawings will be required by the S.E. (PLANNING and WORKS). Any drawing and document submitted for information only should be indicated as such by the Contractor, drawing and documents submitted for information only will not be returned to the Contractor unless the S.E. (PLANNING and WORKS), considers that such drawings needs to be approved, in which case they will be returned suitably stamped with comments. The Contractor shall be responsible for any discrepancies or errors in or omissions from the drawings, whether such drawings have been approved or not by the S.E. (PLANNING and WORKS), approval given by the S.E. (PLANNING and WORKS) to any drawing shall not relieve the Contractor from his liability to complete contract works in accordance with this specification and the condition of contract nor exonerate him from any of his guarantees. If the Contractor needs approval of any drawing within a period of less than four weeks in order to avoid delay in the completion of supply, he shall advise the S.E. (PLANNING and WORKS) when submitting the drawings and provide an explanation of the document’s late submission. The S.E. (PLANNING and WORKS) will endeavour to comply with the Contractor’s time scale, but this cannot be guaranteed. 38. SURFACE TREATMENT A full description of the corrosion prevention system proposed by the bidder shall be given in the schedule and this is subject to acceptance by the S.E. (PLANNING and WORKS), Head of the APDRP. This description shall include details of surface preparation, rust inhibition, paint thickness, treatment of fasteners and paintings of surfaces in contact with oil.


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All machining, drilling, welding, engraving, scribing and graving or other manufacturing activities which would damage the final surface treatment shall be complete before the specified surface treatment is carried out. Any subsequent damage occurring to the surface treatment up to final acceptance shall be made good by the Contractor. 38.1. Painting All paints shall be applied on clean, dry surfaces under suitable atmospheric and other conditions in accordance with the paint manufacturer’s instruction. All paints used shall be compatible with each other and capable of being used as a system. The system shall be capable of performance for five years in the environment specified without any need for maintenance. No consecutive coats of paint shall be of the same shade. The minimum standards acceptable are: • Cleaning by shot blast to Grade Sa 2.5 of ISO 8501 – 1. • All sheet steel surface shall be degreased, pickled and phosphated in accordance with IS 6005 – “Code of

practice for phosphating of iron and steel”. • All rough surface of coatings shall be filled with approved two pack filler and rubbed downto a smooth finish. • Interior surfaces of mechanism chambers, boxes and kiosks, after preparation, cleaning and priming shall be

painted with one coat of zinc chromate primer, one coat of phenolic based undercoating, followed by one coat of phenolic based finishing paint to white colour followed by a final coat of anti-condensation white paint of a type and make to the approval of the S.E. (PLANNING and WORKS). A minimum overall paint film thickness of 150 microns shall be maintained throughout.

• Extra sheet work and metal work, after preparation and priming shall be painted with one coat of zinc chromate primer, one coat of phenolic based under coating and two coats of micaceous iron oxide paint, then painted with a final coat of phenolic based hard gloss finishing paint of the light Grey shade No.631 of IS 5, to provide an overall minimum paint thickness of 200microns.

38.2. Galvanising All galvanizing shall be carried out by hot dip process, in accordance with specification ISO 1460 or IS 2629. However, high tensile steel nuts, bolts and spring washers shall be electro galvanized to service condition 4. the zinc coating shall be smooth, continuous. It shall be free from acid spots and shall not scale, blister or be removable by handling or packing. There shall be no impurities in the zinc or additives to the galvanic bath which could have a detrimental on the durability of the zinc coating. Before pickling, all welding, drilling, cutting, grinding and other finishing operation must be completed and all grease, paint, varnish, oil welding, slag and other foreign matter completely removed. All protuberances which could effect could the life of galvanizing shall also be removed. The weight of zinc deposited shall be in accordance with that stated in standard BS 729, ISO 1460 or IS 2629 and shall be not less than 0.31Kg./m². with a minimum thickness of 86 microns for items of thickness more than five mm., 0.46Kg./m². (64 microns) for items of thickness between 2mm. and 5mm. and 0.33Kg./m². (47 microns) for items less than 2mm. thick. Foundation bolts for structures, however shall be fully galvanized so as to achieve 0.8Kg./m² of zinc coating. Parts shall not be galvanized if their shapes are such that the pickling solution can not be removed with certainty or if galvanized would be unsatisfactory or if their mechanical strength would be reduced. Surfaces in contact with oil shall not be galvanized unless they are subsequently coated with an oil resistant varnish or paint


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In the event of damage to the galvanized the method used for repair shall be subject to the approval of the S.E. (PLANNING and WORKS) or that of his representative. Repair of galvanizing on site will generally not be permitted. The threads of all galvanized bolts and screwed rods shall be cleared or spelter by spinning or brushing. A die shall not be used for cleaning the threads unless specifically approved by the S.E. (PLANNING and WORKS). All nuts shall be galvanized. The heads of nuts shall be cleaned with a tape and the threads oiled. Partial immersion of the work shall not be permitted and the galvanizing tank must therefore be sufficiently large to permit galvanizing to be carried out by one immersion. After galvanizing no drilling or welding shall be performed on the galvanized part of the equipment excepting that nuts may be threaded after galvanizing. To avoid the formation of white rust, galvanized material shall be stacked during transport and stored in such a manner as to permit adequate ventilation. Sodium dichromate treatment shall be provided to avoid formation of white rust after hot deep galvanization. The galvanized steel shall be subjected to test as per IS – 2633. 39. FASTENERS All bolts, studs, screw, threads, pipe threads, bolt heads and nuts shall comply with the appropriate Indian standards for metric threads or the technical equivalent. Bolts or studs shall not be less than 6mm. in diameter accept when used for small wiring terminals. All nuts and pins shall be adequately locked. Whenever possible bolts shall be fitted in such a manner that in the event of failure of locking resulting in the nuts working loose and failing off, the bolt will remain in position. All ferrous bolts, nuts and washers placed in out door position shall be treated to prevent corrosion by hot deep galvanizing, except high tensile steel bolts and spring washers which shall be electro galvanized to service condition four. Appropriate precautions shall be taken to prevent electrolytic action between dissimilar metals. Where bolts are used on external horizontal surface and where water can collect, methods of preventing the ingrees of moisture to the threads shall be provided. Each bolt or stud shall project at least one thread but not more than three thread through the nut, except when otherwise approved for terminal board studs or relay stems. If bolts, nuts are placed so that they are inaccessible by means of ordinary spanners, specials spanners shall be provided. The length of the screwed portion of the bolts shall be such that no screw thread may form part of shear plane between members. The washers shall be provided where necessary. Protective washer of suitable material shall be provided front and back on the securing screws. 40. COMPLTENESS OF CONTRACT All fittings or accessories, although not specifically mentioned herein, but necessary or usual for completion of the substation and its efficient performance shall be provided by the Contractor without extra charge. The bid


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shall clearly indicate if any additional equipment or parts would be necessary to give a complete offer and if so, the details and the prices shall be included in the bid. 41. PADLOCKS. The Contractor shall provide padlockable handles and non-ferrous padlocks with duplicate key for the local control cabinet, mechanism box or kiosk doors to prevent all unauthorized access and operation. 42. LABELS All apparatus shall be clearly labeled indicating, where necessary, its purpose and service positions. The material of all labels and plates, their dimensions, legend and the method of printing shall be subject to approval of the S.E. (PLANNING and WORKS). The surfaces of all labels and plates shall have a mat or satin finish to avoid dazzle from reflected light. Colours shall be permanent and free fading. Labels mounted on black surfaces shall have white lettering. All labels and plates for out door use shall be of non-corroding material. Where the use of enameled iron plates is approved, the whole surface including the back and edges, shall be properly covered and resistance to corrosion. Labels shall be engraved in English with the following exception: • Labels showing the names of high voltage circuits which shall be engraved in English and Oriya. Unless

otherwise specified, name plates shall be provided of white background with black engraved lettering carrying all the applicable information specified in the standards and other details as required by the S.E. (PLANNING and WORKS). the name plate inscription and the size and lettering shall be submitted to the S.E. (PLANNING and WORKS) for approval.

• Danger notice, as specified in the Indian Electricity Rules, shall be affixed permanently in conspicuous positions. They shall have the word “DANGER” and relevant voltage engraved both in English and Oriya in lettering on a white background together with a skull and crossbones in accordance with IS 2551.


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43.2. Technical data schedule

Item Number Description Unit

Bidder’s Offer

1.

2.

3.

4.

5.

6.

Insulation level for which the substation has been designed 33KV Plant and equipment • Power frequency withstand voltage • Switching surge withstand voltage • Lighting impulse withstand voltage 11KV Plant and equipment • Power frequency withstand voltage • Switching surge withstand voltage • Lighting impulse withstand voltage Have the proposed switching schemes been modified (Bidders must attach detail of modification with justification) Busbar layout 33KV busbar conductor type and size Phase specing Current carrying capacity 33KV line bay connection type/size 33KV transformer connection type/size 11KV transformer connection from bushing to UG cable ceiling ends -type/size 33KV busbar/gentry structures: Type (e.g. RSJ, RCC, Steel pipe, lattice steel?) Dimensions of sections used Height Width of sectionaliser bay Width of transformer/line bay 33KV equipment support structures Type (e.g. RSJ, RCC, Steel pipe, lattice steel?) Dimensions of sections used Height 33KV outdoor clearances Phase to Phase Phase to Earth Live on screened parts to ground Sectional clearance

kV kV peak kV peak

kV kV peak kV peak

y/ n

mm. A

/mm ² /mm ² /mm ²

mm x mm mm mm mm

mm x mm mm

mm mm mm

mm


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Bidder’s Offer

7.

8.

9.

9.1.

11KV outdoor clearances Phase to Phase Phase to Earth Live on screened parts to ground Sectional clearance Earth mat design and layout • Standard with which it complies • Type and size of earth grid conductor • Depth of burial of conductor • Safe step voltage • Safe touch voltage • Type of earth electrode • Method of earth transformer 11KV neutral • Method of earthing surge arresters • Method of jointing earth conductors and corrosion

protection of joints - Over ground - Underground LV AC DISTRIBUTION SYSTEM AC distribution board • Name of manufacturer • Type/designation • Standard with it complies • Rated operating voltage • Rated current of outgoing circuits • Short time current with stand rating Current Duration • Rated impulse withstand voltage 1.2/50us. • One minute power frequency withstand voltage • Minimum clearance in air • Crepage distance • Degree of protection of enclosure – IP Code • Total weight of board • Sheet metal details/thickness External surface treatment Internal surface treatment • Dimension (Height, Width, Depth)

mm mm mm

mm

/mm x mm mm V V

V A

kA s

kV mm mm

kg / mm

mm


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Bidder’s Offer

9.2.

9.3.

• Temperature rise: Terminals Busbars and conductors Manual operating means – metallic - Non-metalic accessible external enclosures and covers - Metal surfaces - Insulating surfaces

Moulded case circuit breaker (MCCB) • Manufacturer • Type designation • Standard with which it complies • Rated operating voltage • Rated current • Rated short circuit breaking capacity • Rated short circuit making capacity • Rated short time with stand current

- Duration • Rated impulse with stand voltage 1.2/50us. • Minimum clearance in air • Creepage distance • Over current protection range • Time current characteristic • Definite minimum time lag • Total break time • Total make time • Whether trip free? • Is anti-pumping feature provided? • Total weight of MCCB • Dimensions • Type of contacts • Thickness of plating Miniature circuit breakers (mcbs) • Manufacturer • Type designation • Standard with which it complies • Rated operating voltage • Rated current • One minute power frequency withstand voltage

°C °C °C °C

°C °C

V A kA kA kA s

kV peak mm mm

ms ms y/ n y/ n kg

mm

microns

V A

KV


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Bidder’s Offer

9.4.

• Minimum clearance in air • Creepage distance Instruments and Meters: • Ammeter Governing Standard Make and type Dial size Limits of error in effective range Maximum scale length Short time overload capacity Power consumption Range Temperature compensation details • Voltmeter Governing Standard Make and type Dial size Limits of error in effective range Maximum scale length Short time overload capacity Power consumption Range Temperature compensation details • Watthour meter Governing Standard Make and type Maximum demand integrating period Dial size Whether magnetically shielded Limits of error in effective range Maximum scale length Short time overloaded capacity VA burden Power consumption

Current Coil Voltage Coil

Range Temperature compensation details

mm. mm. mm. mm. Minute/Amps. Watts. mm. mm. Minute/Volt. Watts.


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Technical Data Schedule (Continued) Item

Number Description Unit Bidder’s

Offer 10.

11.

Control building Roof height Area of control room Wall/ceiling finish Area of Store/office Wall/ceiling finish Area of battery room Wall/ceiling finish Area of toilet Wall/ceiling finish Cable trench - dimensions External wall finish Materials: Kiln burnt bricks - manufacturer - type Cement - manufacturer - type High yield strength ribbed steel Reinforcement rods - manufacturer - type G.I. Mild steel angle - manufacturer - type

m.

m² m² m² m² mm.x mm.


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43. NON COMPLIANCE SCHEDULE On this schedule the Bidder shall provide a list of non compliances with this specification, documenting the effects that such non compliance is likely to have on the equipment’s life and operating characteristics. Each non compliance shall be referred to the relevant specification clause. Where are no deviations from specifications, the bidder shall so indicate by stating “No deviations” in this schedule.

Clause No. Non Compliance

44. TEST CERTIFICATES SCHEDULE On this schedule a list of the test certificates included with the bid shall be provided. This list should include type test certificates and sample routine test reports. Each certificate listed shall be reffered to the relevant specification clause and item of equipment to which the test applies.

Clause No. Non Compliance

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