UPS 120, UPS 150, UPS 250, UPS 300, UPS 301, UPS 500, UPS 600, UPS 750 and UPS 900 Uninterruptible Power Supplies Caterpillar

Description

Illustration 1	g01272338
(1) EPO Reset Switch

The Emergency Power Off Reset Switch (EPO) is attached to a EPO circuit breaker that is located behind the locked left door of the MMS System Cabinet. Refer to Illustration 1.

The switch resets the functionality of the EPO after the following events occur:

• The EPO button on the front door has been pushed.

• The system is shutdown.

The EPO breaker disconnects 230 VAC from the system in order for the circuit breaker "K3" to close.

This switch is attached to the AC Interface board (ACI) that is located on the left panel.

Removal Procedure

Refer to Systems Operation, Testing and Adjusting, RENR9988, "Internal Component Preremoval Steps (MMS System Cabinet)" in order to shut down the system and gain access to internal components.

1. Check the labeling of the wires to the EPO reset switch (1). Verify the labeling on the wires to the EPO reset switch (1).

2. Disconnect the wires from the EPO reset switch (1).

3. Remove the EPO reset switch (1) from the metal bracket that connects the switch to the left panel. Compress the rear tabs and orient the "ON" to the top. Pull the switch straight through the hole in the front of the bracket.

Installation Procedure

1. Attach the EPO reset switch (1) to the metal bracket that connects the switch to the left panel.

2. Connect the wires to the back of the EPO reset switch (1).

Illustration 2	g01272344
Wire Connections of the "Style 1" EPO Reset Switch

Illustration 3	g01272343
Wire Connections of "Style 2" EPO Reset Switch

There are two styles of reset switch that are present in the flywheel cabinet. Refer to Illustration 2 and Illustration 3 for the appropriate wire diagram.