KEPCO RA 19-4C Operator Manual - Manual (Page 27)

RA 19-4C 121013
2-9
2.4.2.1 INDIVIDUAL CONTROL
Refer to Figure 2-6 for connections. Each parallel-connected unit must be adjusted within 2% of
each other. The unit with the highest output voltage functions as the master, while the rest are
slaves. In the event of a failure of any power supply, the next highest unit will continue to supply
the load without interruption, making this configuration ideal for N+1 redundancy.
Refer to applicable HSF manual for HSF DIP switch settings required for local (Vadj control) or
remote (external R or V). To adjust output voltage first place the configuration under an operat-
ing load. Then monitor the (+) and (–) test points on the front panel with a precision voltmeter.
For local control turn the HSF Vadj control to the desired operating value. For remote control
adjust the external resistance or voltage source for the desired operating value. Refer to appli-
cable HSF manual for the recommended Adjustment Range of all the HSF Models. Refer to
PAR. 2.4.2.4 for current balancing requirements.
Figure 2-6 shows a configuration in which the master is determined by whichever power supply
has the highest voltage. In this configuration the output voltage of all power supplies must be set
within 2% for current balancing to be in effect. The internal DIP switches, SW1 and SW2, of
each HSF module must be configured to allow control of the output voltage by either a) the HSF
front panel Vadj control (as shown in Figure 2-6) or b) remote control of the output, either by an
external voltage or an external resistance.
This configuration requires that CB (Current Balance) and -COM (negative Common) of all mod-
ules be tied together, using either the DIP switches at the rear of the rack adapter, or by wiring
the I/O mating connector as shown in Figure 2-6. Wiring of the I/O mating connector allows non-
adjacent slots to be connected in parallel. If rack adapter DIP switches are used to connect the
RV and –COM lines, positions 9 and 10 of adjacent modules (DIP 2 and DIP 3 in Figure 2-6)
must be ON (closed). If external wiring of the I/O connector is used, positions 9 and 10 of DIP
switches for adjacent modules (DIP 2 and DIP 3 in Figure 2-6) must be set to OFF (open) and the
RV and –COM connections must be wired at the I/O mating connector as shown in Figure 2-6.
NOTE: When connections are made at the I/O mating connector, use shielded wire for con-
nections to RV pins. Match impedance of load wires between each power supply and
load by using the same wire lengths and wire sizes.