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TPCMQ48 SERIES
INSTALLATION & OPERATING MANUAL
Manual No. tpcmq48-4
tpcmq48-man-rev4-0116.indd
13.0 PARALLEL OPERATION
13.1
Parallel Connection
- Two or more TPCMQ48 modules can be operated in parallel by
connecting their outputs in parallel and connecting their current sense terminals together.
The TPCMQ48 19-inch rack power shelves permit conveniently operating two or three units
in parallel in either redundant mode or non-redundant mode.
13.2
Redundant Operation
- Connecting two TPCMQ48 modules in parallel, with or without
the compatible 19-inch rack, so that the full output load current can be carried by one unit
results in 1+1 redundant operation. While operating normally, the load current is shared
approximately equally between the two units. Should one TPCMQ48 module fail, the full
load is then maintained by the other unit. The failed unit can then be replaced (hot-swap)
without affecting the load current. This operation is facilitated by an active ORing circuit
built into the module. 1+1 redundancy with quick replacement of a failed unit results in
virtually infinite MTBF. 2+1 redundancy works the same way except that the full load is
carried by two out of three units respectively.
13.3
Non-Redundant Operation
- Higher output load currents can be realized by operating two
or three modules in the non-redundant mode to achieve up to 2000 watts for two modules,
3000 watts for three modules. The units are connected in parallel the same as before. In
this case if one unit fails, the load will lose power since only part of the load current can
now be supplied by the remaining module(s), which will go into current limit. The failed
unit can be quickly replaced, however, without turning the power off (hot-swap) to restore
load current.
The number of TPCMQ48 modules that can be operated in parallel is 16. The most convenient
way to parallel large numbers of units is to connect multiple TPCMQ48 19-inch rack power
shelves in parallel.
LOAD
+VOUT
+Sense
Current Share
-Sense
-VOUT
+VOUT
+Sense
Current Share
-Sense
-VOUT
+VOUT
+Sense
Current Share
-Sense
-VOUT
Figure 6 – Connection Diagram for Parallel Operation
