Emerson 7400 Series User Manual page 26

Series 7400 Single Phase 1+N UPS
How to turn ON the System from a Maint. power-down condition
This procedure should be followed to start the one-plus-one from a MAINTENANCE
power-down condition - i.e. where the load is being initially powered through the
internal maintenance bypass supply.
Step Action
1. Check that the UPS mains supply
(and bypass supply, if separate) is
turned on externally.
2. Close the input isolator (and static
bypass isolator if separate.
systems
mounted in auxiliary cubicles).
3. Wait 20 seconds then close the
battery circuit breaker.
4. Press the battery metering selector
switch [B] (S4).
5. Press the Inverter OFF pushbutton
(S6).
6. Close the Output Isolator
7. Open the
Isolator on
Press the Inverter ON switch (S7) on
both modules.
(Note: The inverters of both modules are
inhibited if either modules' Maintenance
Bypass Isolator is closed).
(Complete this action on module at a time)
For 110V
Static bypass isolator
Maintenance Bypass
both modules
Response
Mimic panel LEDs LS1 and LS3 should
illuminate immediately, to indicate that
is the input
healthy.
Inverter will not turn ON unless output
isolator is closed.
Inverter will
configuration at this stage.
Inverter will not turn ON at this stage with
output isolator open if modules are in
1+1 configuration.
Mimic panel LED LS2 should illuminate.
The display should indicate a positive (+)
battery charging current.
Mimic panel LED LS4 should extinguish
Mimic panel LED LS5 should illuminate to
indicate that load is connected to the
static bypass line.
(Note: In a Redundant Module system LS5 will
not illuminate on the second module to be
started as its static bypass line is inhibited).
Mimic panel LEDs LS4 (Inverter OK)
and LS6 (Load on Inverter) should
then
illuminate
seconds.
Module system LS6 will not illuminate
on the first module to be started until
you reach this point in starting the
second module).
LS5 should extinguish at the same
time as LS6 illuminates.
LS7 (alarm) should extinguish.
and bypass supplies
not turn ON for
after approximately
(NB: In a Non-Redundant
are
1+1
30
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