Critical Power
Modifications reserved
Page 17/91
GE_UPS_USM_TLE_SUL_M16_M50_2bU_V010.docx
User Manual
TLE Series 160 - 500 UL S2B
4.3
RPA PARALLEL SYSTEM OPERATION
4.3.1
Introduction to the RPA Parallel System
Fig. 4.3.1-1 Block diagram RPA Parallel System operation
Two or more equal power units can be paralleled to increase the output power (
paralleling for capacity
)
or to improve the overall reliability of an UPS system (
paralleling for redundancy
).
The outputs of parallel units are connected to a common power bus, and in normal operation the units
connected on the parallel bus share the
Load
equally.
The modular concept of
TLE Series
allows parallel operation of up to
6 units
, without using paralleling
switchgear, external bypass circuits or common control circuitry (see
Fig. 4.3.1-1
).
Parallel units for power capacity
Several units can be paralleled in order to achieve output power greater than the maximum power of a
single unit.
The maximum total power shared between the paralleled units is equal to the
total installed nominal
power
.
In the event of a failure of one unit, the power supplied by the UPS system becomes insufficient and the
Load
will be transferred to the
Utility Bypass
source.
Parallel units for redundancy
The nominal power rating of the
n out of n+1
redundant paralleled modules must be equal to or higher
than the required
Load
power.
The
Load
will be equally
shared by the n+1 units
connected on the output bus.
Should
one of the n+1 paralleled units
trip Off-line,
the remaining (n) modules
will supply the
Load
,
maintaining conditioned power to the
critical Load
.
From this results
higher reliability and security for the Load plus a higher MTBF
(Mean Time Between
Failures).
