Vertiv Liebert EXM, User Manual

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Vertiv™ | Liebert® EXM™ UPS 20-100kVA, 50/60Hz User Manual | 31
3.4.5 EPO Input—Optional
NOTICE
Risk of exceeding internal voltage limits. Can cause equipment damage.
Do not apply more than 12V to the Emergency Power Off (EPO) input. Exceeding 12V on this input can damage the
Liebert
®
EXM’s internal circuitry and control boards. Exceeding 12V will also put the Liebert EXM in an EPO state, and the
unit will not reset, making it non-functional.
The UPS has an Emergency Power Off (EPO) function operated by a button on the control panel or by a remote
contact provided by the user. The EPO button is under a hinged, clear plastic shield.
The J2 connector, shown in Figure 18 , is the remote EPO input interface. The EPO has NO/NC contacts that
become active when shorting terminals J2:3 and 4 or open terminal connection J2:2 and 1.
If an external Emergency Stop capability is required, it is connected at terminals J2: 1 and 2 and at J2: 3 and 4 on
the monitor board. It also is connected to the Normally Open or Normally Closed remote stop switch between
these two terminals using shielded cable (see
Figure 18 and Table 8 ). If this function is not used, Terminals J2:3
and 4 must be opened and J2:1 and 2 must be closed.
Figure 18 EPO wiring and signal names for J2
Table 8 EPO input contact relays—J2
Pin Name Description
1 EPO-NC EPO activated when opened to Pin 2
2 + 12V —
3 + 12V —
4 EPO-NO EPO activated when shorted to Pin 3
NOTE
The Emergency Stop action within the UPS shuts down the rectifier, inverter and static bypass. It does not
internally disconnect the input power supply. To disconnect ALL power to the UPS, open the upstream feeder
breaker(s) after the remote EPO is activated.
NOTE
Normally Closed EPO – J2: 12, these terminals are supplied factory-linked on the Bypass Module on the UPS. The
terminals must remain installed if using NO contacts.
NOTE
All auxiliary cables of terminal must be double-insulated. Wire should be 20-16AWG stranded for maximum runs
between 80 and 200 feet (25-60m), respectively.
EPO-NO
12V
J2
12V
EPO-NC
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