Emerson 7400 - Manual (Page 28)

19
Series 7400 Single Phase 1+N UPS
IMPORTANT
The Maintenance Bypass Isolator may be operated at any time when the UPS is
powered down to connect / disconnect each load to the raw maintenance bypass
supply if required.
Emergency Stop
The emergency stop pushbutton is located behind a hinged safety shield to prevent
inadvertent operation. When this switch is pressed both modules are electronically
shut down and both battery circuit breakers are tripped. Power is removed from the
critical load, but pressing the emergency stop pushbutton will not remove the
modules’ input mains supply unless an external contactor, controlled via the
emergency stop pushbutton, is fitted in the mains supply line.
How to totally Power down the System
This procedure should be followed only if the one-plus-one AND LOAD are to be
completely powered down.
Step Action Response
1. Press the Inverter OFF switch (S6)
on both modules.
2. Open the battery circuit breaker.
3. Open the input isolator (and static
bypass isolator also. For 110V
systems Static bypass isolator is
mounted in auxiliary cubicles).
Mimic panel LEDs - LS4 and LS6 should
extinguish and LS5 should illuminate to
show that the load has been transferred
to the static bypass line.
(Note: In a Non- Redundant Module system LS5
and LS6 will also changeover on the second
module)
Mimic panel LEDs LS2 should
extinguish.
All the operator panel led indications and
messages should extinguish as the
mains driven internal power supplies
decay.