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UPS 20-40 kVA, 230/400 V 50/60 Hz output
User’s Guide
1025358
Revision D
Operating system bypass switch
The system bypass switch is used to bypass the parallel system during maintenance or
servicing. Maintenance bypass switch is located on the front panel of the optional SPM cabinet.
using the switch does not cause any break in the output voltage, if the input voltage and
frequency are accepted and the system is synchronised to the input mains.
SPM-30-2 and SPM-60-2
The parallel module includes a mechanical bypass switch S3 (Make-Before-Break type) and
two maintenence switches S1 and S2 for disconnecting the outputs of UPS modules during
maintenance or service.
The maintenance bypass switch has the following positions:
•
‘I’ or ‘UPS’ normal position, the load is supplied from the UPS modules.
•
‘II’ or ‘BYPASS position, the UPS modules are bypassed and the critical load is supplied
from the system bypass power line.
SPM-30-4 and SPM-40-4
The parallel module includes a mechanical bypass switch S5 (Make-Before-Break type) and four
maintenance switches S1, S2, S3, and S4 for disconnecting the outputs of UPS modules during
maintenance or service.
The maintenance bypass switch has the following positions:
‘I’ or ‘UPS’ normal position, the load is supplied from the UPS modules.
‘I’+’II’ or ‘UPS+BYPASS’ position, the load is supplied from UPS modules (internal bypass
mode) and the system bypass in parallel.
‘II’ or ‘BYPASS’ position, the UPS modules are bypassed and the critical load is supplied from
the system bypass power line.
If the system bypass switch needs to be used it is recommended to check that the bypass input
power is connected and present in the SPM cabinet. The swicth is used only on rare occasions
and the procedure is following:
1.
Check that the ‘bypass not available’ alarm is not active in the UPS modules.
(Press menu button, choose UPS status display).
2. Use LCD to turn UPS unit(s) on internal bypass mode.
Select: CONTROL
->
GO TO BYPASS MODE
3. Verify the transfer before proceeding the next step.
4. Turn the maintenance bypass switch to BYPASS position.
Warning
The use of the maintenance bypass switch will cause a break in the output
voltage if the input voltage or frequency is not correct and the UPS system is not
sychronised to mains.