There are manual pushbuttons located on the front of the Circuit Breaker (K8) that will open and close the breaker.
Note: Opening the breaker will cause the customer load to be de-energized.
The top side of the Circuit Breaker (K8) contains a bank of terminal strips. The terminal strip sends the status of the Circuit Breaker (K8) to the External Source Sync Board (ESS) in the 4-Wire Transformer cabinet. In a 3-pole circuit breaker application, the neutral current transformer is wired into this terminal strip for grounding purposes.
The front of the Circuit Breaker (K8) contains control inputs that set the overcurrent trip levels of the breaker. This Circuit Breaker (K8) is coordinated with the rest of the UPS system so these settings should never be changed.
Removal Procedure
- Perform steps in Systems Operation, Testing and Adjusting, "Internal Component Preremoval Steps (4 Wire Output Cabinet)"in order to de-energize the system and gain access to internal components.
- Make sure the unit is either locked out or tagged DO NOT OPERATE.
- Remove all fuses.
- Make sure the generator engine is stopped.
- Make sure all batteries are disconnected.
- Make sure all capacitors are discharged.
- Make sure residual voltage in the rotor, stator and the generator is discharged.
- Disconnect the wire harness connector from the cabinet wiring.
 |
When servicing or repairing electric power generation equipment: Failure to do so could result in personal injury or death. |
 |
- Remove the 12 bolts that connect the connectors for the Circuit Breaker (K8) to the four vertical bus bars on the top side of the Circuit Breaker (K8).
- Remove the 16 bolts that connect the Circuit Breaker (K8) to the four lower bus bars at the bottom of the Circuit Breaker (K8).
- Remove the four bolts at the back bottom of the Circuit Breaker (K8) that hold the lower rail of the Circuit Breaker (K8) to the cabinet frame.
Refer to bolt locations in Illustration 1.
- Remove the three bolts on front of the mounting base of the Circuit Breaker (K8) that hold the Circuit Breaker (K8) to the frame.
Refer to Illustration 1.
Note: The Circuit Breaker (K8) weighs 80 kg (176 lb). It is recommended that two people and/or machinery are used to remove a breaker.
- Remove the breaker from the cabinet.
- Remove the rear bus duct for installation in the new Circuit Breaker (K8).
Installation Procedure
- Ensure the settings on the front of the new breaker match the old breaker.
For the location of the input panel see Illustration 1 and Illustration 3. If these settings cannot be determined, refer to Systems Operation, Testing and Adjusting, "Specifications".
 | |
| Illustration 1 | g01271162 |
Circuit Breaker (K8), 4-pole (3) Circuit Breaker I/O, Top (4) Wire Terminal (5) Wire Harness Connector (6) CB Rail (7) Control Panel (8) Circuit Breaker I/O, Bottom | |
 | |
| Illustration 2 | g01271163 |
Circuit Breaker (K8), 3-pole (1) Neutral Current Transformer (2) Cable (Neutral Current Transformer) (3) Circuit Breaker I/O, Top (4) Wire Terminal (5) Wire Harness Connector (6) CB Rail (7) Control Panel (8) Circuit Breaker I/O, Bottom | |
 | |
| Illustration 3 | g01271166 |
Control Panel For The Circuit Breaker (K8) (10) LCD Display (11) LED Indicators (12) Red Test Button (13) Spring Charge Status Indicator (14) Green Breaker ON Button (15) Manual Charge Spring Lever (16) Red Breaker OFF Button (17) Breaker Status Indicator | |
- Attach the rear bus duct from the old Circuit Breaker (K8) to the new Circuit Breaker (K8).
- Place the new breaker in the cabinet.
- Attach the rear CD rail to the cabinet frame with four bolts.
Refer to Illustration 1.
- Attach the front edge of the base plate for the Circuit Breaker (K8) to the cabinet frame with three bolts.
- Attach the four lower input bus bars of the Circuit Breaker (K8). Insert four bolts from the bottom through the output bus bars and the inputs for the Circuit Breaker (K8).
- Attach washers and nuts as indicated in Illustration 4.
Note: In all cases the side of the belleville washer that curves inward should be placed facing the bus bar.
- Attach the four vertical output bus bars to the four outputs at the top of the Circuit Breaker (K8). Insert four bolts in each bus bar, from the back side of the output bus bars.
- Attach washers and nuts as indicated in Illustration 4.
 | |
| Illustration 4 | g01271171 |
(20) Nut (21) Belleville Washer (22) Grade 8 Coated Steel Washer (23) Bus Bars (24) Bolt | |
- Connect the harness wire connector to the cabinet wiring.
See Illustration 5 for 3-pole configuration and Illustration 6 for 4-pole configuration.
 | |
| Illustration 5 | g01271167 |
Wire Terminal Connections For The Circuit Breaker (K8), 3-pole | |
 | |
| Illustration 6 | g01271169 |
Wire Terminal Connections For The Circuit Breaker (K8), 4-pole | |
- Tighten all 24 bus bar hex nuts to 150 N·m (110 lb ft).
Always tighten the hex nut, not the bolt.