Modulon NH Plus Series
5-6
5-7 Manual Bypass Startup Procedures (Parallel Redundancy)
5-7-1 Online Mode Transfers to Manual Bypass Mode
1. Press the “
O
” button of the UPS that you want to shut down for 3 seconds until you
hear a “beep” and then release the button. The LCD screen will show
“SHUTDOWN
UPS?”
, then select
“YES”
and press
“
”
to confirm.
- If the other UPS can take over the total loads, then the turned-off one will shut down
the inverter. The LCD screen shows
”LOAD NOT POWERED”
for the turned-off
one. The working UPS shows
”ONLINE MODE”
.
- If the total loads are greater than one UPS can take over, then both UPSs will shut
down the inverter and transfer to bypass mode. Both UPSs show
”ON AUTO
BYPASS”
.
2. Repeat Step 1 for another UPS.
3. Switch
off
“Q1”
of both UPSs.
4. Confirm if both UPSs are completely shut down.
5. Switch on “Q3” of both UPSs. Bypass power source supplies the loads. The LCD
screen shows
”ON MANUAL BYPASS”
.
6. Switch
off
”Q4”
and
”Q2”
of both UPSs. The LCD screen will be off.
7. Switch off battery circuit breaker of the external battery cabinet.
8. In this mode, only
”Q4”
and terminal block has hazard voltage. Service personnel can
perform maintenance work.
5-7-2 Transferring from Manual Bypass Mode to Online Mode
1. Switch on the battery circuit breaker of external battery cabinet.
2. Switch
on
”Q2”
and
”Q4”
of both UPSs.
Switch off
”Q3”
of both UPSs.
The LCD screens of both UPSs show
”ON AUTO
BYPASS”
.
3. Switch
on
”Q1”
of both UPSs.
4. Press
the
“
I
” button for 3 seconds until you hear a “beep” and then release the button.
5. Repeat Step 5 to start up another UPS. When the inverter voltage of both UPSs
activates normally, both UPSs will transfer to normal mode at the same time.
Only for maintenance purpose, you can manually turn on the bypass switch. If you
switch on Q3 under normal status, the inverter will shut down and the output will
be supplied by manual bypass source.
