CG Switchgear and ControlA Business Unit of Crompton Greaves Ltd.

TECHNOLOGY TO THE FORE

SWITCHGEARC O M P L E X

SF6-GAS CIRCUIT BREAKERSFOR OUT-DOOR USE UPTO 36kV

INTRODUCTIONMore than 9000 Crompton Greaves SF6 GasCircuit Breakers with puffer type interruptors upto420 kV have been put into service in variousenvironments in many countries since 1983 wherethey are operating satisfactorily.Type SFGP SF6 Circuit Breakers are of live tank typewith rated voltage of 24 & 36 kV. Each breakerconsists of three puffer type interruptors,providing a high insulation as well as an excellentbreaking capability, a spring operating mechanismensuring high operational reliability.All our SF6 Gas Breakers (24 to 420 kV) adhere tothe requirements of the quality standards and scopeof supply of ISO 9001, 1994.

FEATURESThese SF6 Gas Circuit Breakers are extremely simpleand compact in their design owing to the fact thatno gas blast valves or exhaust valves are requiredand the force of contact separation simultaneouslydrives the puffer piston, which builds up the gaspressure according to the contact stroke. The struc-tural simplicity results in high performancereliability and, therefore, minimal inspection andre-assembly. Also this ensures that themaintenance time is low. Inspection is simple andeasy since the interrupting medium, which is alsothe insulating medium, is monitored with easethrough clearly readable pressure gauges andmechanical as well as electrical interlocks.The breaker opens from front as well as backpanels to provide easy access to all parts of themechanism. The checking or replacing of fixed,moving or arc contacts and nozzle can be done byremoving only the upper terminal of the interruptorunit as and when required. This operation does notrequire the breaker to be dismantled and it takesonly a few hours to put the breaker back intoservice.The low operating noise level of the spring chargedoperating mechanism used in this breaker enablesits use in residential areas. All exposed ferrous partsare treated to give high corrosion resistance andare finally painted with polyurethane based paintensuring excellent finish and protection. The breakerhas been made extraordinarily simple and light toincrease safety in the event of earthquakes.

INTERRUPTER UNIT - FIG1

OPERATING MECHANISM - FIG2

TECHNOLOGY TO THE FORE

SWITCHGEARC O M P L E X

Exploded schematic view ofthe operating mechanism

Motor

Spur gear

Closing trigger

Roller

Closing latch

Plunger core (closing coil)

HookInterlock spring

Link

Closing cam

Cam rollerPlunger core (tripping coil)

Hook

Tripping trigger

Roller lever

Cam shaftCrank lever

Crank pin

Connectingrod

Push rod

Tripping latch

Latch arm

Closingspring

Eccentric crankshaft

Ratchet wheelPawls

Main shaft

Main-shaft lever

Roller

Tripping spring

Absorbent

Stationary contact holder

Stationary contact

Gas flowArc

Nozzel

Moving arc contact

Moving main contact

PistonPuffer cylinder

Main contact

Contact spring

TESTS AND PERFORMANCEThe performance and reliability of these breakers and their excellent interrupting capability has been verified at renownedinternational testing laboratories like CESI, Italy and CPRI, India. The breakers are type tested for short circuit duties and capacitivecurrent switching test as per IEC 56-1987

EASE OF INSTALLATIONSince these units are shipped in two parts - namely the pole unit and the mechanism - minimal site preparation is required and setuptime is very low.

DESIGNThe interrupting unit (FIG.1) is puffer type and is contained in a porcelain insulator and the terminals. During interruption the puffercylinder is quickly driven downwards with its attached parts by the operating mechanism (from the breaker "closed" position to thebreaker "open" position). The gas within the puffer cylinder is compressed by the piston and blown to the arc through the nozzleachieving arc extinction.The operating mechanism (FIG.2) is an easy to handle motor charged spring type. It also permits manual operation of the breaker. Highreliability has been ensured by keeping the number of components to a minimum and, therefore, maintenance required is easy andminimal.

GUARANTEED TECHNICAL PARTICULARS24 / 36 kV SF6 GAS CIRCUIT BREAKER

UNITS 24 kV 36 kV

1. TYPE REFERENCE : - 20-SFGP-25A 30-SFGP-25A 30-SFGP-40A2. RATED VOLTAGE : kV 24 363. RATED LIGHTNING IMPULSE WITHSTAND VOLTAGE : kVp 150 2004. RATED POWER FREQUENCY WITHSTAND : kV 60 805. CREEPAGE DISTANCE (TOTAL) : mm 600 9166. APPLICABLE STANDARDS : - IEC 56, BS 5311 & JEC 1817. TYPE OF MECHANISM : - SPRING CLOSING / TRIPPING8. RATED NORMAL CURRENT : A 1250, 1600, 20009. RATED SHORT CIRCUIT BREAKING CURRENT : kAp 25

10. RATED SHORT CIRCUIT MAKING CURRENT : kA 62.511. RATED OPERATING SEQUENCE : - O-0.3 sec-CO-15 sec-CO12. RATED FREQUENCY : Hz 50 / 6013. RATED BREAK TIME : ms 8014. RATED CLOSING TIME : ms 10015. RATED CLOSING / TRIPPING VOLTAGE : V 110 / 220 VDC16. CURRENT OF CLOSING / TRIPPING COIL : A 5 at 110 VDC17. FIRST POLE TO CLEAR FACTOR : - 1.518. RATED DURATION OF SHORT CIRCUIT : sec 319. RATED CABLE CHARGING BREAKING : A / pu 50, <2.5

CURRENT AND OVER VOLTAGE.20. RATED SINGLE CAPACITOR BANK BREAKING : A / pu 440, <2.5

CURRENT AND OVER VOLTAGE.21. RATED OUT OF PHASE BREAKING CURRENT : kA 6.25 1022. AUXILLIARY CONTACTS : - 5 NO + 5 NC23. SF6 GAS PRESSURE (AT 20 ºC)

-NORMAL : Kg / cm2 5-GAS FEED ALARM : Kg / cm2 4.5-LOCKOUT : Kg / cm2 4

OPTIONALS

1. CREEPAGE DISTANCE 25, 31, 35 mm / kV2. CLOSING / TRIPPING COIL VOLTAGE 24 / 30 / 60 / 110 / 125 / 220 VDC3. CLEARANCE OF LIVE PARTS TO GROUND AS PER CUSTOMER SPECIFICATION4. ALTITUDE ABOVE SEA LEVEL UPTO 2500 M5. AUXILLIARY CONTACTS 10 NO & 10 NC6. LIGHTNING IMPULSE WITHSTAND VOLTAGE 250 kVp7. EARTHQUAKE WITHSTAND (SEISMIC ACCELERATION) 0.3 g / 0.5 g

25 & 4062.5 & 100

6.25 & 10

The Thapar GroupCG-S&C/EXP/Cat.No.SF6-102/3/01/2000

Data subject to change

CG Switchgear and ControlA Business Unit of Crompton Greaves Ltd.

Switchgear ComplexA-3, MIDC, Ambad, Nashik - 422 010 IndiaTel: (+91) 253 382271 to 75 Ext 107/108/110Fax: (+91) 253 382219/381247E-mail: exports@cglmail.com (Exports)

mktg@cglmail.com (General)URL: www.cgswgear.com

FOUNDATION PLAN DETAILS

DETAILS OF TERMINAL PAD(MATERIAL - AL, 22 THK)

GAS SYSTEM

GENERAL OUTLAY

1. INTERRUPTER2. SUPPORT PORCELAIN3. BASE FRAME4. MECHANISM HOUSING5. SUPPORT STRUCTURE

F

G

C

E

H

A A

B

D

1

2

3

4

5

FOUNDATION BOLT(M24×400) LOCATION250 50

80

4801100

450

900

Ø14, 4 HOLES

Ø15, 4 HOLES

1644.5 60

140

4040

40

150

44.5

15CO

ND

UC

TO

RS

IDE

BR

EA

KE

RS

IDE

DIMENSIONS (mm)

A B C D E F G H TOTAL WEIGHT (Kg)

20-SFGP-25A 600 1560 3349 680 1025 522 2783 502 675(24 kV)

30-SFGP-25A 750 1860 3819 680 1225 672 3103 502 750(36 kV)

30-SFGP-40A 750 1860 4079 680 1290 976 3103 502 750(36 kV)

A-Phase B-Phase C-Phase

Arcing column

Stop valve

Pressure gauge

Stop valveBlind cap

Temperaturecompensatedpressure switch

Gas pipe

Regd. Office :6th Floor, CG House, Dr. Annie Besant Road,Prabhadevi, Mumbai -400 025, India.