MGE UPS Systems Comet Series Installation And User Manual page 49

3.4.6.2 From Maintenance
Bypass to Normal
mode
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The cooling fans will remain operational when the UPS is placed on
Maintenance Bypass mode to prevent the optional input/output
transformers inside the UPS from overheating. If it is necessary to de-
energize the fans, move the fan control switch (SR2) to the "OFF"
position.
In this mode of operation, the UPS is ready for maintenance, but
voltage is still present on terminal blocks and various internal
components.
Failure to follow the proper Start-Up sequence will result in load loss.
After SR1 is set to "TRANSFER," it takes the UPS five (5) to six (6)
seconds to test the input power before turning on the "Static Switch."
During this time, the load is still supplied by the Maintenance Bypass
line, and moving SR1 to "NORMAL" will result in interruption of power
to the load.
Installation and Users Manual
NOTE
CAUTION
Now the UPS is ready for maintenance.
WARNING
1. Move the fan control switch (SR2) to the "ON" position if
the cooling fans were de-energized during
maintenance.
2. Turn the manual bypass switch SR1 to the
"TRANSFER" position.
3. Wait for the alarm and diagnostics display to go on (at
least 5 seconds).
Operation 3 — 13