Normal, Battery, And Bypass Modes With Parallel Operation: 7−2 - Eaton Powerware 9315 Installation And Operation Manual

During maintenance, the output of the system can be supplied power through the
bypass breakers in the SBM or the optional System Maintenance Bypass (SMB).
The bypass input and breaker must be rated for the total system load since it must
supply all of the system load when on bypass. Manual transfers between the
bypass source and the paralleled UPMs are verified make before break.
For manual transfers to bypass, the static switch is not used. During the transfer,
CBP is closed and verified and then CBS is opened. For transfers of the load from
bypass to the UPMs, CBS is closed and verified and then CBP is opened. The
static switch is armed and ready during both types of transfers.
Communications is required between the SBM and UPMs in the system for full
system operation. System level communications and control are accomplished
using a dual redundant network known as PowerNet. PowerNet consist of two
independent networks that are connected to each component network node in the
parallel system.
Data is always transmitted on both networks simultaneously. Each network node
monitors both PowerNets. Failure of one of the two will only result in an alarm
condition. In addition, the applications at each node are designed such that
messages can be lost on the network without affecting the operation of the system.
7.2 Normal, Battery, and Bypass Modes with Parallel
Operation:
With the Parallel Capacity/Redundant system, the system continues to function
automatically to supply AC electrical power to the critical load. There are three
standard operation modes and one optional mode in this system:
•
In Normal mode, the Parallel Capacity/Redundant system functions normally,
suppling clean, filtered power from the UPMs to the load.
•
In Bypass mode, the SBM bypass input supplies the load and isolates the
UPMs.
•
In Battery mode, the battery cabinet supplies DC power, which maintains UPM
operation.
•
In Maintenance Bypass mode (optional), the SMB bypass supplies the load and
isolates the SBM and UPMs for maintenance purposes.
The following descriptions provide the Parallel Capacity/Redundant system
operating mode differences.
7−2 EATON Powerware 9315 Parallel Capacity/Redundant System
164201150 Rev. E www.powerware.com