GE Industrial Solutions TLE Series 225-500 User Manual - Manual (Page 16)

Critical Power
Modifications reserved Page 16/90
GE_UPS_USM_TLE_SUL_M22_M50_1US_V010.docx User Manual TLE Series 225 - 500 UL S1
4.2.5 Automatic Bypass
In normal operation, the Load is supplied by the
Inverter.
When the control system detects a fault in the
Inverter, an overload condition or a short-circuit
condition, the Automatic Bypass will transfer the
critical Load to the Utility without interruption.
When the Inverter recovers, or the overload or
short-circuit condition is corrected, the Load will
be automatically transferred back to the Inverter.
Fig. 4.2.5-1 Block diagram Automatic Bypass
If the UPS is unable to return to normal mode following an automatic transfer to Bypass mode, an
alarm condition will be initiated.
A Manual Bypass (operator initiated) will not be considered as an alarm condition.
In case of RPA Parallel System
Each unit has its own internal Bypass.
These units are continuously exchanging information, enabling all of the internal Bypass circuits in a
Parallel System to operate simultaneously.
If the Inverter of a unit fails, its Bypass circuit remains available to the Parallel System.
It is excluded only if the unit is separated from the common bus by opening its output switch Q1.
4.2.6 Manual Bypass
The Manual Bypass circuit consists of manual
switches Q1 and Q2, which permits transfer of
the Load directly to the unconditioned AC power
without interruption, leaving the UPS available
for maintenance.
Fig. 4.2.6-1 Block diagram Manual Bypass