Critical Power
Modifications reserved
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GE_UPS_ISG_TLE_SUL_40K_M15_1US_V010.docx
Installation Guide TLE Scalable Series 40 - 150 UL S1
4.9
RPA PARALLEL SYSTEM CONNECTION
WARNING !
This operation must be performed by trained personnel before the initial start-up
(ensure that the UPS installation is completely powered down).
4.9.1
Power wiring of parallel units
To guarantee good Load sharing between the units of a Parallel System, we recommend that the cable
length from the input distribution board (5) to the output distribution board (9) is equal for each unit (a+b
= c+d = e+f = g+h = i+l = m+n = o+p = q+r).
Tolerance: +/-10%.
The AC input power of the Bypass must be the same for all units of the Parallel System - no phase shift
allowed between units.
NOTE !
It is strongly recommended that no transformers, automatic circuit breakers or
fuses should be inserted between the unit’s output and the
Load
common bus bars.
However, it is recommended that a disconnection or isolation switch is installed in
order to totally isolate a unit if needed.
Verify that power wiring and control wiring run in separate conduits or cable trays.
The power wiring requires two separate conduits: one for input and one for output cables.
Fig. 4.9.1-1 Power wiring of RPA Parallel System
1 = Rectifier
2 = Inverter
3 = Automatic Bypass
4 = Input Utility Distribution
5 = Unit Output Load
6 = External Battery MCB
7 = External Battery
8 = Common bus bar and
Output Load Distribution
= UPS number 1
= UPS number 2
= UPS number 3
= UPS number 4
= UPS number 5
= UPS number 6