B&K Precision 1730A - Manual - Manual (Page 20)

19
CONNECTING TWO POWER SUPPLIES IN PARALLEL
Two power supplies may be connected in parallel to double the maximum load current. In this configuration, two 1710As will
provide a variable 0-30 volt output at up to 2 amps; two 1730As will provide a 0-30 volt output at up to 6 amps (heavier gauge
hook-up leads are advisable). Current equalizing resistors must be used as shown in Fig. 9. However, the protective current
limiting feature will prevent damage if current is temporarily unbalanced during set -up.
When connected in parallel and operating in the constant voltage mode, determine the total load current limit and preset the
current limiting for each power supply to half the total load current value. Then when the load is connected, set the VOLTAGE
controls on the two power supplies for equal voltage readings on the V meters. This should also provide approximately equal
current from each supply, as read on the A meters. Add the two A meter readings together for total load current, or connect an
external ammeter in series with the load.
If the current equalizing resistors are not well matched, it is preferable that the voltages be slightly unbalanced to achieve
current balance. Be sure that the supplies are adequately balanced so that both remain in the CV mode.
When connected in parallel and operating in the constant current mode, the VOLTAGE controls of both supplies should be
preset to the same value. Then when the load is connected, the CURRENT controls of the two supplies should be adjusted for
approximately equal current from each unit. Be sure that both supplies remain in the CC mode.
OPERATING INSTRUCTIONS