GE Industrial Solutions SG Series 750 T12 UL S2 User Manual - Manual (Page 49)

Modifications reserved Page 49/71
OPM_SGS_USM_M75_M75_2US_V010.doc User Manual SG Series 750 UL S2 & SG Series 750 T12 UL S2
7.1.2 UPS shutdown with Load transfer on External Maintenance Bypass (option)
NOTE !
Not following this procedure can cause protected loads to shut down!
Never close or open either UPS Output Switch Q1 and External Maintenance
Bypass Switch (option) with the Inverter running!
Initial situation: the Load is powered by the Inverter.
If eBoost™ option is available, make sure that eBoost™ Operation Mode is
disabled before starting this procedure.
The complete UPS system has to be turned OFF, while providing the Load power
by Utility through the External Maintenance Bypass (option).
With the UPS in normal operation and the Inverter supplying the Load, the UPS Output Switch Q1 and
the Input Circuit Breaker CB4 are closed (Pos. I).
External Maintenance Bypass Switch (option) is open and the Battery Circuit Breaker is closed (Pos. I).
The Synoptic Diagram must display the status “LOAD
SUPPLIED BY INVERTER”.
1. Disconnect the Inverter by pressing the “Inverter OFF” ( O ) key and hold until the LED 5
(Inverter available) turns OFF.
The Load is transferred to Utility by Automatic Bypass.
Inverter shuts down. LED 5 (Inverter available) must be OFF.
LED Alarm is lit and the LED Operation is Off.
The Synoptic Diagram must display the status “LOAD
SUPPLIED BY AUTOMATIC BYPASS”.
2. Transfer the Load from Internal Automatic Bypass to External Maintenance Bypass (option).
Use the External Maintenance Bypass panel instructions to transfer the Load from the UPS Automatic
Bypass to External Maintenance Bypass Breaker (MBB).
After this step, the Load is supplied by the Utility through the UPS Automatic Bypass and the External
Maintenance Bypass (option).
3. Open the UPS Output Switch Q1 (Pos. O) and then press the “Load Off” key.
The Load is now supplied only through the External Maintenance Bypass (option).
Rectifier shuts down and all input and output contactors are opened.
Press the “MUTE” key to reset the alarm buzzer.
4. Disconnect the battery by opening the Battery Circuit Breaker.
Wait 5 minutes for DC-Link Capacitors discharge.
The Load is now powered from the Utility through External Maintenance Bypass (option).
END OF PROCEDURE
WARNING!
It will take a minimum of 5 minutes for the DC capacitors to discharge.
Open only the front door, do not open any other part of the UPS.