Installation manual

4-12

Wiring

The 8720MC-RPS Regenerative Power Supply boosts up and

controls the DC bus voltage, by utilizing the magnetic

characteristics of a reactor. Therefore, reactors are required for the

8720MC-RPS Regenerative Power Supply.

Install a single-phase type reactor to each of L

-phase, L

-phase and

-phase. Do not use three-phase AC reactors, since this will cause

unwanted coupling between the phases.

The following inductance of the reactor must be maintained in a

high frequency as 10 to 20 kHz. Note that use of a reactor for

commercial power supply may not maintain the required

inductance, resulting in increased heat generation or saturation due

to iron loss.

When multiple units are connected in parallel, a current unbalance

between the units is produced due to variation of reactor

inductance. To make the current difference between the connected

units as small as possible, use reactors having a variation of no

more than +/-2.5%.

For Model 8720MC-RPS065BM and 8720MC-RPS065BS units:

Allen-Bradley - 100-C43x10 (CE marked) (where x

is voltage suffix code of operating

coil)

Fuji Electric - SC-N2S (UL listed component)

(Select an adequate operating coil for the magnetic contactor

within the range of 100 to 230 VAC depending on the used

voltage.)

Be sure to provide required quantity of magnetic contactors (MC)

for all units connected in parallel (see Figure 4.2 or 4.3).

Installing Reactor

ATTENTION

: During operation of the 8720MC-RPS

Regenerative Power Supply, the reactor is at a high

temperature. Do not touch the reactor during

operation or immediately after the unit has been

turned OFF. Failure to observe this precaution could

result in bodily injury.

ATTENTION

: During operation of the 8720MC-RPS

Regenerative Power Supply, the reactor operates at a

high temperature. Install the reactor in a location

where high temperature does not present a problem.