UPS 750 Uninterruptible Power Supply Caterpillar

Illustration 1	g03693642
(5) Vacuum Gauge Location, front view (6) Vacuum Gauge

Vacuum Gauge

The thermocouple vacuum gauge is located on the top of the flywheel assembly. The gauge measures the vacuum in the flywheel assembly. The gauge reports the amount of vacuum to the flywheel interface PWA which reports value to the APC3. There is an RJ-45 connector on the side of the gauge.

Removal

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

   Note: The flywheel cabinet must be de-energized before removal steps can be performed.

2. Remove the eight bolts from the top cover of the flywheel assembly.

3. Disconnect RJ-45 cable.

4. Unscrew the gauge from the flywheel housing using 11/16 inch wrench.

Installation

1. Screw vacuum gauge into flywheel housing until snug using 11/16 inch wrench.

2. Reconnect RJ-45 cable to vacuum gauge.

3. Install the top cover of the flywheel assembly with the eight bolts that were removed earlier.