UPS 750 Uninterruptible Power Supply Caterpillar

PWA Breaker Controller Interface Board

Illustration 1	g03789077
(1) Breaker controller interface board location

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Breaker controller interface board

The breaker controller interface board (BCI) is located behind the left door panel of the SIO cabinet. The BCI board monitors and controls the K1, K2, K3, and the K4 contactors. The BCI board also monitors power supply status, inductor temperatures, bypass SSD, and EPO.

Removal

1. Refer to Systems Operation, Test and Adjust, UENR4695, "Internal Component Pre-Removal Steps". Perform the internal component pre-removal procedure to shut down the system and to gain access to internal components.

   Note: The system must be shut down before removal steps can be performed.

2. Disconnect all connectors from the board. The connectors are labeled to match the appropriate location. Verify that the labeling for each connector is present and legible.

3. Disconnect the nine white plastic stand-offs that the board is mounted to. Use the following method.

   Note: The board must be removed from the stand-offs without bending the board.

   1. Pinch the head of each stand-off so that the board is not locked to the stand-off but is still attached to the stand-off.

   2. Remove the board by gently and evenly pulling the board from all stand-offs at the same time.

Installation

1. Install the board in the correct position over the nine white stand-offs that are connected to the swing-out panel.

2. Push the board, gently and evenly, onto all the stand-offs simultaneously.

3. Plug the wire connectors into the correct locations on the board. Check the labels on each connector for proper placement.