Understanding Parallel Capacity/Redundant System Operation
The Switchboard System Bypass Module (SSBM) supports the normal operation of the Powerware 9315 Parallel Capacity/Redundant system by offering parallel capacity/redundant capability. The Parallel Capacity/Redundant system continues to maintain power to the critical loads during commercial electrical power brownout, blackout, overvoltage, undervoltage, and
If utility power is interrupted or falls outside the parameters specified in the Powerware 9315 Operation manual, the Parallel Capacity/Redundant system uses a backup battery supply to sustain power to the critical load for a specified period of time or until the utility power returns. For extended power outages, the backup battery supply allows you to either transfer to an alternate power system (such as a generator) or shut down the critical load in an orderly manner. Refer to the Powerware 9315 Operation manual provided with the UPMs for operation of the UPMs.
7.1Looking Inside the Parallel Capacity/Redundant System
The output of the system is normally supplied by several Uninterruptible Power Modules (UPMs). Multiple UPMs are connected with their outputs in parallel to provide a load level greater than the rating of one UPM and for redundancy. The paralleled UPMs supply the output load with protected power as long as the load does not exceed the combined rating of the paralleled UPMs.
The power system is denoted redundant as long as one of the UPMs can be disconnected from the output bus and the remaining UPMs can continue to supply power to the load without exceeding their ratings.
The SSBM, contains switchgear and components that allow the the UPMs to be paralleled and the source of system output power to be transferred between Bypass and the paralleled UPMs.
When the load is being supplied by the UPMs, the system output bus is continuously monitored by the SSBM for an over or under voltage condition. If an out of limits condition is detected, the SSBM will transfer the load to bypass using a high speed emergency bypass. The transfer will occur in less than 4 milliseconds.
The emergency bypass consist of a static switch, a wraparound bypass breaker (CBP) and a backfeed protection breaker (FBP). The backfeed protection breaker is located in series with the static switch. If an SCR shorts, the breaker will open so that the UPMs will not backfeed the bypass source, dropping the load when a utility outage occurs.
Powerware 9315 Parallel Capacity/Redundant System with PHP SSBM | |
164201373 Rev. A 092402 |
|
