Emergency Power Off
EPO Overview
The Emergency Power Off (EPO) option is a safety feature that will immediately disconnect all connected equipment from utility power. The UPS will immediately shut down and will not switch to battery power.
Connect each UPS to the EPO switch.
The UPS must be manually restarted to reapply power to connected equipment. Press ON/OFF on the front panel of the UPS.
Normally open contacts
1. If the EPO switch or relay contacts are normally open, insert the wires
from the switch or contacts at pins 1 and 2 of the EPO terminal block. Use
2. Secure the wires by tightening the screws.
If the contacts are closed, the UPS will turn OFF and power will be removed from the load.
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Normally closed contacts
1. If the EPO switch or relay contacts are normally closed, insert the wires from the switch or contacts at pins 2 and 3 of the EPO terminal block. Use
2.Insert a wire jumper between pins 1 and 2. Secure the wires by tightening the three screws at positions 1, 2, and 3.
If the contacts are opened, the UPS will turn OFF and power will be removed from the load.
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Note: Pin 1 is the power source for the EPO circuit, it provides a few milliampere of 24 V power.
If the normally closed (NC) EPO configuration is used, the EPO switch or relay should be rated for "dry" circuit applications, the rating should be for low voltage and low current applications. This normally implies the contacts are
Adhere to all national and local electrical codes when wiring the EPO. Wiring must be performed by a qualified electrician.
The EPO interface is a Safety Extra Low Voltage (SELV) circuit. Connect the EPO interface only to other SELV circuits. The EPO interface monitors circuits that have no determined voltage potential. SELV circuits are controlled by a switch or relay properly isolated from utility power. To avoid damage to the UPS, do not connect the EPO interface to any circuit other than a SELV circuit.
Use one of the following cable types to connect the UPS to the EPO switch.
•CL2: Class 2 cable for general use.
•CL2P: Plenum cable for use in ducts, plenums, and other spaces used for environmental air.
•CL2R: Riser cable for use in a vertical run in a
•CLEX: Limited use cable for use in dwellings and for use in raceways.
•Installation in Canada: Use only CSA certified, type ELC,
•Installation in countries other than Canada and the USA: Use standard
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