7.3.2Redundant CBP Mode (Optional)
The Parallel Capacity/Redundant system can be protected against failure of the CBP breaker to close if an electrically interlocked System Maintenance Bypass (SMB) with Redundant CBP controls has been provided. The Redundant CBP controls protect the critical load against power losses caused by CBP close failures during manual or automatic operations.
Redundant CBP operations can be recognized by an alarm condition at the SSBM and the following breaker conditions:
CBP OPEN
CBS OPEN
FBP OPEN
MIS CLOSED
MBP CLOSED
CAUTION:
The critical load is not protected while the Parallel Capacity/Redundant
system is in Maintenance Bypass or Bypass mode.
Once Redundant CBP operation has occurred, the SSBM must be isolated to allow CBP breaker maintenance without impact on the system’s critical load. To achieve SSBM isolation, the Redundant CBP controls have been interlocked with the System Maintenance Bypass controls. To exit from Redundant CBP operation, the SMB control switch must be turned to the TO MAINT position. This action opens the UPS system MIS breaker and places the the UPS system fully into Maintenance Bypass mode.
After the CBP breaker has been repaired, the UPS system can be transferred from Maintenance Bypass mode to Bypass mode as described above.
Figure 7---7 shows the path of electrical power through the Parallel Capacity/Redundant system when operating in Maintenance Bypass mode.
Powerware 9315 Parallel Capacity/Redundant System with PHP SSBM | |
| 164201373 Rev. A 092402 |
