Maintenance Bypass Procedure - Toshiba 4200FA User Manual

5.19 Maintenance Bypass Procedure

When operating the Maintenance Bypass, the following operation procedure should be used:
WARNING
From UPS to Maintenance Bypass
1) Move the "STOP/RUN" key switch, located on the front panel, to "STOP."
2) Verify that step one above is followed, and that the Bypass light indicator on the
3) Locate the Maintenance Bypass Rotary Switch (middle front panel of the UPS);
4) Turn off MCCB1 breaker labeled "MAIN POWER SWITCH."
The unit is now in the Maintenance Bypass mode and may be serviced. For units with an internal
isolation transformer, the transformer is still active.
From Maintenance Bypass to UPS
1) Verify that the "STOP/RUN" switch is in the "STOP" position. Turn on MCCB1
2) Wait until the output fans turn on (This is a good indication that the unit is in the
3) For units with an external battery cabinet, turn on MCCB1 "BATTERY CABINET."
4) Locate the Maintenance Bypass Switch (Middle front panel of the UPS) slowly
5) Rotate the "STOP/RUN" switch to the "RUN" position.
6) Verify that the Inverter indicator light on the front panel is lit.
The unit is now back On-Line and supplying conditioned power to the load.
TOSHIBA
Failure to adhere to the following instructions could result in damage to your
equipment and/or you risk removal of power to any equipment attached to
the UPS.
Operation of the UPS inverter stops. Output power is now provided to the load
through the Bypass circuit. While in this mode, if a power failure occurs on the
commercial power source, the UPS will lose power. Power to the critical
load device will be interrupted. The battery charging circuit and chopper circuit
remains active.
front panel is lit.
slowly rotate the Cam Switch clockwise until "BYPASS MODE" Position is
reached.
"MAIN POWER SWITCH."
Bypass mode), and that the Bypass indicator light on the front panel is lit.
rotate the Cam Switch counter-clockwise until "UPS MODE" Position is reached.
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