LVSB SYSTEM & OPERATION

EXERCISE 5

LVSB SYSTEM & OPERATION

LVSB SYSTEM & OPERATION

LEARNING OUTCOME

1. To familiarize with Low Voltage Switch Board (LVSB) systems

2. To demonstrate skill in LVSB operation.

CONTENT

5.1 THEORY

Makmal Elektrik Industri, Jabatan Kejuruteraan Elektrik Kuasa, Fakulti Kejuruteraan Elektrik dan Elektronik (UTHM) had six (6) sets of industrialLow Voltage Switchboards which shall be configured for practical application as an integrated electrical training system for the faculty engineering students.

Figure 5

LVSB SYSTEM & OPERATION

familiarize with Low Voltage Switch Board (LVSB) systems. (C3

demonstrate skill in LVSB operation. (A2-LO9)

Makmal Elektrik Industri, Jabatan Kejuruteraan Elektrik Kuasa, Fakulti Kejuruteraan Elektrik dan Elektronik (UTHM) had six (6) sets of industrialLow Voltage Switchboards which shall be configured for practical application as

d electrical training system for the faculty engineering students.

Figure 5.1: Low voltage Switch Board.

. (C3-LO2)

Makmal Elektrik Industri, Jabatan Kejuruteraan Elektrik Kuasa, Fakulti Kejuruteraan Elektrik dan Elektronik (UTHM) had six (6) sets of industrial-type Low Voltage Switchboards which shall be configured for practical application as

d electrical training system for the faculty engineering students.

5.1.1 Each set of the LV Switchboards comprise the following: 1. 600 A, Main Switchboard 1 (MSB incomer No.1) c/w capacitor bank

panel. 2. 600 A, Main Switchboard 2 (MSB incomer No.2) c/w capacitor bank

panel. 3. 100 A, Essential Switchboard c/w auto-change over contactor & local

wheel. 4. 100 A, Automatic Mains Failure (AMF) Board c/w local wheel

A. MSB No.1 and MSB No.2 The 600 A, MSB No.1 and MSB No.2 comprise two (2) panels, P01 and P02, and mounted on a steel frame with four (4) numbers nylon wheels for mobility. The switchboards are designed for rear access that is to say that all external cabling has to be carried out at the rear of the panel. The back of the switchboards are constructed and fabricated with clear polycarbonate Perspex sheets to enable visibility of the components with the panel door closed. Panel 01 of MSB No.1 and MSB No.2 are identical with the exception that MSB No.1 is provided with a Digital Power Meter (DPM) and MSB No.2 is equipped with the analogue ammeter, voltmeter and power factor meter with the associated selector switches; as seen on the respective MSB together with the two sets of phase indication lights. Panel 01 also houses the 640 A, incoming ACB, IDMT over current and earth fault relay, Kilo-Watt Hour (KWH) meter, switchboard anti-condensation heater switch and heater indication light and Electronic Surge Protector (ESP). Panel P02 of the MSB includes a busbar compartment for the vertical busbar connections to various outgoing circuits from the main horizontal busbars at the top of the switchboard. Panel 02 of MSB No.1 and MSB No.2 are also identical with the exception that MSB No.1 is equipped with the Key Exchage Box for the key interlocking system.

B. Essential Switch Board (ESB) The ESB is provided with voltmeter, ammeter, their respective selector switches and two sets of phase indication lights for the incoming supplies from the normal source (TNB) and from the emergency supply source (standby generator). The 100 A, TPN MCCB with shunt trip for the incoming supply and 100 A Automatic Transfer Switch (ATS) with status indication lights for the normal and generator supply source and the following are also provided with the ESB. Had 60 A TPN MCCB, 30 A TPN MCCB and 30 A SPN MCCB for the various outgoing circuits.

Figure 5

C. Automatic Main Failure (AMF) The top of the AMF panel houses the voltmeter, ammeter with the respective selector switches, kilo-Watt (kW), Power Factor (PF), generator Hour Run (HR), Frequency (Hz) meters and a set of phase indication lights incoming supply from the emergency supply source (standby generator). The AMF channels the power supply from the standby generator via the 100 A, TPN MCCB with shunt trip coil and protected by the over current and earth fault relay. The lower compartment of the AMF houses the control circuitry with an industrial-type diesel standby generator complete with DC ammeter and voltmeter to monitor the battery condition of the generator, various generator alarms, indicating lights, control push buttons and switches.

Figure 5.2: Essential Switch Board (ESB).

Automatic Main Failure (AMF)

The top of the AMF panel houses the voltmeter, ammeter with the respective Watt (kW), Power Factor (PF), generator Hour Run (HR),

Frequency (Hz) meters and a set of phase indication lights incoming supply source (standby generator).

The AMF channels the power supply from the standby generator via the 100 A, TPN MCCB with shunt trip coil and protected by the over current and earth fault

The lower compartment of the AMF houses the control circuitry for interfacing type diesel standby generator complete with DC ammeter and

voltmeter to monitor the battery condition of the generator, various generator alarms, indicating lights, control push buttons and switches.

The top of the AMF panel houses the voltmeter, ammeter with the respective Watt (kW), Power Factor (PF), generator Hour Run (HR),

Frequency (Hz) meters and a set of phase indication lights incoming supply

The AMF channels the power supply from the standby generator via the 100 A, TPN MCCB with shunt trip coil and protected by the over current and earth fault

for interfacing type diesel standby generator complete with DC ammeter and

voltmeter to monitor the battery condition of the generator, various generator

Figure 5

D. Integrated Electrical Training System

The LV Switchboards have been setup, cabled and interconnected to operate as the Integrated Electrical Training System, simulating a typical industrialapplication, which essentially is diagram in Figure 5.4. Two main switchboards (MSB No.1 and MSB No.2), each with its own power supply source with busbar coupling facilities complete with a keysystem. The Integrated Electrical Training System is supplied with an ESB complete with Auto Transfer Switching (ATS) facilities; this comprises a 4changeover contactor with the ATS Controller. As in any industrial-type application, the ATS Controller is programmed to detect failure of the normal power source and detects the availability of the standby power supply source, which, when detected, the ATS would initiate the changeover contactor to operate. Upon failure of the normal power supply source, the ATS Controller iprogrammed to initiate a signal to AMF and thence to the generator to startUpon return of the stabilized normal power supply source, the ATS Controller would then command the generator for shut

Figure 5.3:Automatic Main Failure (AMF).

Integrated Electrical Training System

The LV Switchboards have been setup, cabled and interconnected to operate as the Integrated Electrical Training System, simulating a typical industrialapplication, which essentially is represented in the schematic single line

Two main switchboards (MSB No.1 and MSB No.2), each with its own power supply source with busbar coupling facilities complete with a key-interlocking

Training System is supplied with an ESB complete with Auto Transfer Switching (ATS) facilities; this comprises a 4-pole automatic changeover contactor with the ATS Controller.

type application, the ATS Controller is programmed to ct failure of the normal power source and detects the availability of the

standby power supply source, which, when detected, the ATS would initiate the changeover contactor to operate.

Upon failure of the normal power supply source, the ATS Controller iprogrammed to initiate a signal to AMF and thence to the generator to startUpon return of the stabilized normal power supply source, the ATS Controller would then command the generator for shut-down of the generator.

The LV Switchboards have been setup, cabled and interconnected to operate as the Integrated Electrical Training System, simulating a typical industrial-type

single line

Two main switchboards (MSB No.1 and MSB No.2), each with its own power interlocking

Training System is supplied with an ESB complete pole automatic

type application, the ATS Controller is programmed to ct failure of the normal power source and detects the availability of the

standby power supply source, which, when detected, the ATS would initiate the

Upon failure of the normal power supply source, the ATS Controller is also programmed to initiate a signal to AMF and thence to the generator to start-up. Upon return of the stabilized normal power supply source, the ATS Controller

Figure 5.4: LVSB Integrated Training System.

5.2 EQUIPMENT LIST

5.2.1. Low Voltage Switch Board 1 unit

5.2.2. Safety helmet 1 unit

5.2.3 Safety boots 1 unit

5.2.4 Safety glasses 1 unit

5.2.5 Gloves 1 set

5.2.6 Insulated rubber mats 1 unit

ACTIVITIES Acvitivity 1 (Busbar Coupling of MSB1 & MSB2) :

1. Turn on MSB1 main isolator (Observe the Main Supply indicator light -

RYB). Charging the ACB and turn it on (Observe the Busbar Supply indicator light - RYB).

2. Turn on MSB2 isolator (Observe the Main Supply indicator light

Charging the ACB and turn it on (Observe the Busbar Supply indicator light - RYB).

Figure 5.5: Busbar Supply & Main Supply indicator light.

3. In this position there are two transfo

main switchboards.

4. Make sure in the normal conditions, key C1 and C2 are trapped in the Key Exchange Box (Panel P02

Figure 5

5. Make sure keys K are trapped in the ACBs in Panel P01MSB2.

RYB). Charging the ACB and turn it on (Observe the Busbar Supply

Turn on MSB2 isolator (Observe the Main Supply indicator light Charging the ACB and turn it on (Observe the Busbar Supply indicator

.5: Busbar Supply & Main Supply indicator light.

In this position there are two transformer sources feeding into separate

Make sure in the normal conditions, key C1 and C2 are trapped in the Key Exchange Box (Panel P02-1 of MSB1)

Figure 5.6: Key Exchange Box.

Make sure keys K are trapped in the ACBs in Panel P01-2 of MSB1 and

RYB). Charging the ACB and turn it on (Observe the Busbar Supply

Turn on MSB2 isolator (Observe the Main Supply indicator light - RYB). Charging the ACB and turn it on (Observe the Busbar Supply indicator

rmer sources feeding into separate

Make sure in the normal conditions, key C1 and C2 are trapped in the Key

of MSB1 and

Figure 5.7: K key position in ACB

6. Either MSB1 or MSB2 shall be switched OFF by the lab instructor (for

example, MSB1 will be OFF). Then you need to coupling the supply from MSB2 to support MSB1 panel.

7. Remove the respective interlocking K key from the ACB and used to release the trapped keys C1 and C2 in the Key Exchange Box.

Figure 5.8: Remove K key from ACB and lock it to Key Exchange Box.

8. The two isolator interlocking keys C1 and C2 shall be used to free the interlocks on the bus-tie isolators in MSB1 and MSB2 respectively.

Figure 5.9: Remove C1 key and lock it to MSB2 interlock isolator key.

Figure 5.10: Free the interlock isolator

9. Both interlock isolators now free to be switched ON thus completing the busbar coupler operation.

10. The respective busbar supply indicator lamps indicate that the respective panel being energized by the other the panel.

11. Record the voltage reading for this panel.

Figure 5.11: Busbar Supply indicator lamps ON, although Main Supply OFF.

12. Lab instructor will record the time taken to complete the busbar coupler

operation for each personnel starting from either MSB1 or MSB2 being switched OFF.

Activity 2 (Normal Supply Restored) : 1. Performed reverse operation to release the trapped K key for one of the

ACBs. Switched OFF the bustie isolators, release the C keys which are then inserted in the respective keys slots in the Key Exchange Box.

2. Release the K key to free the ACB interlock.

3. Switched ON the respective ACB to have the normal supply.

4. Record the voltage reading for this panel.

5. Lab instructor will record the time taken to complete this operation starting from the supply back to normal condition.

Figure 5.12: Pumping and ON the respective ACB.

Figure 5

Lab instructor will record the time taken to complete the busbar coupleroperation for each personnel starting from either MSB1 or MSB2 being

2 (Normal Supply Restored) :

Performed reverse operation to release the trapped K key for one of the ACBs. Switched OFF the bustie isolators, release the C keys which are then inserted in the respective keys slots in the Key Exchange Box.

key to free the ACB interlock.

Switched ON the respective ACB to have the normal supply.

Record the voltage reading for this panel.

Lab instructor will record the time taken to complete this operation starting from the supply back to normal condition.

.12: Pumping and ON the respective ACB.

Figure 5.13: Normal supply condition.

Lab instructor will record the time taken to complete the busbar coupler operation for each personnel starting from either MSB1 or MSB2 being

Performed reverse operation to release the trapped K key for one of the ACBs. Switched OFF the bustie isolators, release the C keys which are then inserted in the respective keys slots in the Key Exchange Box.

Lab instructor will record the time taken to complete this operation starting

Activity 3 (ESB – Automatic Transfer Switching) : 1. Turn ON ACB for MSB1 and MSB2. For this time considered, MSB2 as a

alternative supply (generator set). 2. At MSB2, make sure the 100A TPN MCCB at plate P02-2 is in OFF

position. 3. At MSB1, turn on 100A TPN MCCB at plate P02-2 (ESB normal supply).

For about 5 seconds, observe the indicator lights of normal supply at ESB panel.

Figure 5.14: Normal supply indicators is ON at ESB.

4. Observe the supply voltage received by ESB. 5. Switch of the main isolator for MSB1 considered the normal supply is

interrupted. Observe the normal supply indicator lights at ESB.

6. At MSB2 (which considered as genset supply), turn on 100A TPN MCCB at plate P02-2 to ON position.

7. For about 5 seconds, observe the Genset supply indicator lights at ESB. Record the voltage reading.

Figure 5.15: Genset supply indicators are ON at ESB.

Activity 4 (Normal Supply Restore

1. Switch ON MSB1 main isolator, observe the normal supply indicator lights at ESB, record the voltage reading.

2. Turn OFF MSB2 main isolator (Genset shutdown). Observe the indicator lights at ESB.

Activity 5 (Questions)

1. Briefly explain the function of

2. Briefly explain the function of Essential Switch Board (ESB).

3. Briefly explain the function of Automatic Main Failure Board (AMF).

REFERENCE

1. Paul Gill; Electrical Power Equipment Maintenance & testing; Taylor & Francis (1998).

2. Robert W. Seaton; William H. Ubert; Switchgear & Control Handbook (3th Edition); McGraw Hill (1998)

.15: Genset supply indicators are ON at ESB.

Activity 4 (Normal Supply Restored) :

Switch ON MSB1 main isolator, observe the normal supply indicator lights at ESB, record the voltage reading.

Turn OFF MSB2 main isolator (Genset shutdown). Observe the indicator

Briefly explain the function of four (4) pole isolator.

Briefly explain the function of Essential Switch Board (ESB).

Briefly explain the function of Automatic Main Failure Board (AMF).

Paul Gill; Electrical Power Equipment Maintenance & testing; Taylor &

Robert W. Seaton; William H. Ubert; Switchgear & Control Handbook (3th Edition); McGraw Hill (1998)

Switch ON MSB1 main isolator, observe the normal supply indicator lights

Turn OFF MSB2 main isolator (Genset shutdown). Observe the indicator

Briefly explain the function of Automatic Main Failure Board (AMF).

Paul Gill; Electrical Power Equipment Maintenance & testing; Taylor &

Robert W. Seaton; William H. Ubert; Switchgear & Control Handbook (3th