Vertiv Liebert APM2 - Host Communication Port

Figure 4.11 REPO Port
Pin Name Meanings Pin Name Meanings
1 EPO-NC EPO activated when opened to Pin 2 3 + 12 V
EPO activated when shorted
to Pin 4
2 + 12 V EPO activated when opened to Pin 1 4 EPO-NO
EPO activated when shorted
to Pin 3
Table 4.10 Description of REPO Port
WARNING! The UPS emergency shutdown action will shut down the rectifier, inverter and static bypass, but
will not disconnect the UPS input mains from the inside. If it is necessary to completely power off the UPS,
after triggering EPO, it is also necessary to disconnect the external power switch, bypass input switch,
output switch and battery switch. EPO requires the use of shielded cables.
The EPO is triggered when the pins 3 and 4 are shorted or the pins 2 and 1 are opened.
If an external EPO function is required, pins 1 and 2 or 3 and 4 are reserved for this function. The external EPO facility is also
connected to the normally open or normally closed remote EPO switch between these two terminals using shielded cable. If
this function is not required, pins 3 and 4 must be opened and pins 1 and the 2 must be closed.
NOTE: The EPO action of the UPS shuts down the rectifier, the inverter and the static bypass, but it does not
internally disconnect the mains input power supply. To disconnect all power to the UPS, open the external power
switch, bypass input switch, output switch and BCB after the EPO is activated.
4.2.8 Host communication port
This port monitors and sets parameters through connecting with computer.
The communication port provides serial data and is intended for use by authorized commissioning and service personnel in
UPS commissioning and service. Refer to Vertiv™ Liebert® APM2 Option Configurations on page155.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual