Service manual

Always On UPS Systems Inc

- Indicators will show normal rectifier and inverter operation of the system.

Record UPS status

o Out of service, bypass mode

o Status form

12. UPS SHUTDOWN PROCEDURES

12.1. Complete UPS shut down procedure

a. Switch off the inverter – The inverter can be switched off by simultaneously

pressing the inverter off switch (O) and the inverter control switch (◄►). The

load will be automatically transferred to reserve without interruption.

b. Open the battery fuse holder and or breaker – This will disconnect the batteries

from the DC bus and the UPS no longer has back up available. This fuse holder

or breaker can be located within the UPS system or within the battery cabinets.

c. Open the rectifier breaker – Opening the rectifier breaker will remove the

power source from the DC bus. The DC bus will start to drop slowly until it

reaches a save level of approximately 20VDC.

WARNING!

Completing the next step will turn off the power to the loads.

Make sure all loads have been turned off before proceeding.

d. Open the Reserve breaker – Before opening the reserve breaker you must make

sure there is no critical load connected to the UPS that requires power. NO

OUTPUT POWER WILL BE SUPPLIED FROM THE UPS ONCE THE

RESERVE (UTILITY) BREAKER IS OPENED.

e. Open the Input breaker – transformers will de-energized.

f. Now that all power has been cut off within the UPS system. All LED’s, displays

and fans should be off.

12.2. From Inverter To Manual Bypass Procedure

The following procedures will allow the service personnel to switch the UPS

system to manual or maintenance bypass mode without interrupting the output

power to the loads.

a. Switch off the Inverter – The inverter can be switched off by simultaneously

pressing the inverter off switch (O) and the inverter control switch (◄►). The

load will be automatically transferred to reserve (utility) supply without

interruption.

b. Open the battery fuse holder and or breaker– This will disconnect the batteries

from the DC bus and the UPS no longer has back up available. This fuse holder

or breaker can be located within the UPS system or within the battery cabinets.

c. Open the Rectifier breaker – Opening the rectifier breaker will take the power

source away from the DC bus, therefore, the DC bus will start to drop slowly.

After 5 min., the DC bus will drop to a safe level (approx. 20VDC).