Separate (Shutdown) A Ups Unit From The Parallel System (System Redundancy) - GE LP 33U Series Operating Manual

7.2.4 Separate (shutdown) a UPS unit from the Parallel System (System Redundancy)

One UPS unit of the Parallel System has to be turned Off, while the load is shared between the other
units supplying the parallel bus.
1. Disconnect the inverter, only on this unit, by pressing "Inverter OFF" ( O ) key and hold until the
LED Inverter (7) turns OFF.
With redundant system, pressing the key OFF the inverter shuts down and it will stay OFF.
If by pressing the key "O" the load is transferred to the utility and the inverter remains operating, it means the
system is not redundant.
In this case is not possible to switch-OFF one unit without transferring the load on utility).
Load supplied from inverter(s) of the other Unit(s) of the Parallel System.
2. Open the output switch Q1 only on this unit.
LED Alarms is lit and the LED Operation is Off.
3. Perform the command "Total Off" only on this unit.
Perform the command "Total Off" by entering the screen (see
Section 6.5):
COMMANDS / REQUEST TOTAL OFF
4. Switch OFF battery breaker only from battery cabinet belongs to this unit..
5. In order to discharge the DC link capacitors, insert the inverter by pressing "Inverter ON" ( I ) key
only on this unit.
Remark:
Command INVERTER ON will be enabled only when the inverter
voltage of each phase decreases below 7 Vac (about 30 seconds).
Before proceeding to step 6, check on the display panel that the DC
link voltage (both polarities) Vp and Vn has reached the max.
voltage of 5 Vdc (about 30 seconds).
The acoustical alarm is activated, press "MUTE" key (from Home
screen) to reset it.
6. Disconnect the inverter, only on this unit, by pressing "Inverter OFF" ( O ) key and hold until the
LED Inverter (7) turns OFF.
7. Switch OFF the utility power, only on this unit, at the AC input distribution panel.
WARNING !
In case the unit should be disconnected and removed from the operating system, the
operation MUST BE PERFORMED BY QUALIFIED PERSONS.
If an intermediate unit must be disconnected from a parallel system pay attention do not
open the control bus: keep the plugs J3 and J4 connected to the board "P16 - Connector
adapter RPA" (See Chapter 3.9.5 of Installation Guide).
For any further intervention contact nearest Service Center.
Modifications reserved
OPM_LPS_3UO_50K_60K_1US_V010.doc
END OF PROCEDURE
Home\Commands
COMMANDS
RESET TOTAL OFF
REQUEST TOTAL OFF
Home\Meter
INVERTER
f :
L1 :
L2 :
L3 :
T :
SYNCHRONIZED
Home\ Meter
BOOSTER
f :
L1 :
L2 :
L3 :
Vp :
Vn :
Operating Manual LP 33U Series 30 & 40 kVA
60.0 Hz
7 V
7 V
7 V
OK
60.0 Hz
120 V
120 V
120 V
5 V
5 V
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