KEPCO RKW 600W Series Operator Manual - Manual (Page 12)

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RKW 600W 060110
5.3 PARALLEL CONNECTION
Identical RKW 600W Power Supplies can be connected in parallel (with or without N+1 redun-
dancy). Current balancing per PAR 5.3.1 can be implemented. Parallel units can be configured in
a master-slave configuration so that all units can be adjusted using on Vadj control, either for mul-
tiple loads (PAR 5.3.2.1) where current draw is dependant upon the individual loads, or for a sin-
gle load (PAR 5.3.2.1), where current balancing (forced current sharing) per PAR 5.3.1 equalizes
the load among the parallel-connected units.
For a single remote ON-OFF signal to turn off all parallel-connected units, connect together all
+RC terminals and connect together all –RC terminals.
Figure 9 illustrates connection of up to four (maximum) power supplies in parallel. Output current
for a parallel connection operating into a single load must be equalized per PAR 5.3.1 after con-
necting the CB terminals as shown in Figure 9. Refer to PAR. 5.3.1 for conditions required for
proper current equalization (balancing).
N+1 Redundancy. An N+1 system requires one additional power supply than necessary to supply
the load. If one of the parallel-connected units fail, the others will seamlessly provide power to the
load without down time. For N+1 redundancy, add isolation diodes as shown in Figure 9.
FIGURE 9. PARALLEL CONNECTION WITH CURRENT BALANCING
5.3.1 CURRENT BALANCING
Current balancing (equalization) conditions required for up to four RKW 600W units in parallel are:
1. Output current of each power supply should be within 20 to 90% of the total output current
rating.
2. The output voltage of any Power Supply individually must be within 2% maximum of the
other power supplyies’ output voltage setting.
variation of output voltage in each power supply
3. The expected current sharing is such that the output current variation for each power supply
is less than or equal to 10% of each power supply rated output current.
5.3.2 MASTER-SLAVE CONFIGURATIONS
Master-slave operation allows the output voltage of all the power supplies connected in parallel to
be adjusted using the Vadj control on the designated master power supply.
Maximum Voltage Minimum Voltage –
Rated Voltage
------------------------------------------------------------------------------------------------------- 2 % =