Parallel Ups Shutdown With Load Transfer On Manual Bypass Q2 - GE 8 Series Operating Manual

8.2.2 Parallel UPS shutdown with load transfer on manual bypass Q2

NOTE !
Not following this procedure can cause protected loads to shut down!
Never close or open either Q1 or Q2 with the inverter running!
Initial situation: the load is powered by all inverters of the Parallel System.
The complete UPS Parallel System has to be turned OFF, while providing the load
power by mains through all manual bypass switch Q2 of the Parallel System.
With the UPS Parallel System in normal operation and the inverters supplying the load, the switches Q1
and Q4 are closed (Pos. I), Q2 are open (Pos. O) and the battery fuses F8 – F9 are inserted.
The synoptic diagram, on all UPS units, must display the status
"LOAD SUPPLIED BY INVERTER".
1. Disconnect the inverter by pressing "Inverter OFF" ( O ) key and hold until the LED Inverter (5)
turns OFF on all UPS units.
At no redundancy, the system will transfer to mains supply.
LEDs Alarms are lit and the LEDs Operation are Off.
The synoptic diagram, on all UPS units, must display the status
"LOAD SUPPLIED BY AUTOMATIC BYPASS".
2. Close the manual bypass switch Q2 (Pos. I) on all UPS units.
LED 9 (manual bypass Q2) lights up on all UPS units as soon as the first switch Q2 shuts down
Load is now supplied from mains in parallel from automatic bypass and manual bypass Q2 of all UPS units.
3. Open the output switch Q1 (Pos. 0) on all UPS units.
The load is now supplied only through the manual bypass Q2.
4. Press "Load Off" key on all UPS units.
The output contactor K6 open and LED 8 (load on automatic bypass) is OFF.
5. Open the input rectifier switch Q4 (Pos. 0) on all UPS units.
The acoustical alarm is activated, press "MUTE" key to reset it.
6. Disconnect the battery removing the battery fuses F8 – F9 on all UPS units.
The electronic boards and the control panel are still powered from AC power supply through the plug X8 on
the "P1 - Power Interface" (Warning! This board will remain powered from the mains throughout this
procedure!).
The acoustical alarm is activated, press "MUTE" key to reset it.
The load is now powered directly by mains through all
MANUAL BYPASS Q2.
WARNING!
It will take 5 minutes for the DC capacitors to discharge
Open only the front door, do not open any other part of the UPS.
Modifications reserved
OPM_SPE_XXX_10K_40K_8GB_V020.doc
Page 77/99
Operating Manual SitePro 10-15-20-30-40 kVA / S8