Emerson FPC Manuel D’Utilisation

NEC Article 645 requires that emergency power off (EPO) switches be located at the principal room 

exits. All standard Liebert power conditioning systems have provisions for external shutdown control 

from Remote Emergency Power Off (REPO) stations. Figure 14 is a simplified diagram of the shut-

down circuitry of the Liebert FPC.

Control wiring connections must comply with the NEC and all other applicable codes.

As shown in Figure 14, the control circuit operates on 24VDC. The shutdown device (represented by 

the REPO switch) activates a low-current, 24VDC relay that in turn operates the shunt-trip mecha-

nism. The shunt-trip solenoid opens the Main Input Breaker, which de-energizes the power center.

When more than one power center is installed by the user, a typical requirement is that actuation of a 

single device (REPO for example) must shut down all power centers. The low-voltage control circuits 

of all standard Liebert FPC systems are designed to meet this requirement.

External control wiring connections for remote shutdown, alarm, and/or monitoring are made to the 

low-voltage junction box (if used) or to the low-voltage control terminal strip located inside the unit.
Control wiring connections vary with the type of monitoring system furnished with the unit. Two typ-

ical control wiring configurations are shown in Figures 15 and 16.

Verify that all incoming high-voltage (power) and low-voltage (control) circuits are

de-energized and locked out before installing cables or making connections, whether in the 

junction box or in the unit.

B

9

6

3

7

4

1

A