Powerware BPIV 30 kVA Installation & Operation Manual page 37

You can transfer the Parallel System from Normal mode to Bypass mode manually.
However, the Parallel System switches automatically to Bypass mode whenever the
UPMs can no longer supply the critical load. If the Parallel System transfers to
Bypass mode from Normal mode due to an output voltage deviation, the Parallel
System automatically attempts to transfer back to Normal mode (up to three times
within a 10-minute period). The fourth transfer or an overload condition will lock the
critical load on the bypass source and requires operator intervention to transfer.
Bypass mode is a normal operating mode, and not an alarm condition. However, if
the Parallel System is unable to return to Normal mode following an automatic
transfer to Bypass mode, an alarm condition is recorded.
Powerware BPIV Parallel Cabinet Installation and Operation
164201409 REV. B 101503
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