UPS 1000S/ UPS 1200S Uninterruptible Power Supplys Caterpillar

Illustration 1	g01280788
Inverter Module Locations (1) Inverter Module 1A (2) Inverter Module 2A (3) Inverter Module 2B (4) Inverter Module 2C (5) Inverter Module 3A (6) Inverter Module 3B

There are six Inverter Modules that are located in the Inverter Cabinet.

Each complete inverter assembly includes the following components: an inverter module, DC capacitors, an AC fuse, a positive DC bus fuse and a negative DC bus fuse.

Illustration 2	g01280789
Complete Inverter Assembly (7) DC Capacitors (8) Negative DC Bus Fuse (-) (9) Heat Sink (10) Digital Gate Logic Board (11) Positive DC Bus Fuse (+) (12) AC Fuse

Illustration 3	g01280797
Complete Inverter Assembly, Expanded View (13) AC Fuse (14) DC Capacitors (15) Negative DC Bus Fuse (-) (16) Positive DC Bus Fuse (+) (17) Heat Sink (18) Digital Gate Logic Board

Illustration 2 and Illustration 3 show the complete inverter assembly for Inverter 1. Inverter 2 is the same unit rotated 180 degrees for installation.

Removal

Inverter Pre-Removal Steps

1. Perform steps in the Systems Operation, Testing and Adjusting, "Internal Component Preremoval Steps (Inverter Cabinet)" in order to de-energize the system and gain access to internal components.

2. Open the DC Disconnect in each of the Flywheel Cabinets.

   Make sure that the green light is ON before operating the DC Disconnect Switch.

3. Confirm that the voltages are zero using a digital multimeter.

4. Remove the vertical fan plenum in order to expose the inverter heatsinks.

   There are 12 bolts. Use a 178 mm (7/16 inch) socket.

Inverter Module Assembly Removal

1. Remove the clear plastic cover over the Digital Gate Logic Board of the Inverter Module Assembly to be removed. Three cross head screws.

2. Remove the connectors from the Digital Gate Logic Board. The wires locations are labeled. Verify the labeling.

3. Cut the tie-wraps in order to move the cables out of the way.

4. Remove the toroid wire assembly that is bolted to the bottom of the bracket for the Digital Gate Logic Board.

5. Remove the bolt from the bracket of the Inverter Module Assembly that holds the assembly to the cabinet frame.

6. Remove the four bolts that connect the Inverter Module Assembly to the DC Capacitor Assembly fuse bus. Use a 229 mm (9/16 inch) deep socket.

7. Remove the bolt that connects the Inverter Module assembly to the AC Fuse Assembly. Use a 229 mm (9/16 inch) socket.

8. Slide out the Inverter Module Assembly straight forward.

AC Fuse Assembly Removal

1. Remove the bolt from the bracket that connects the AC Fuse Assembly to the Inverter Module Assembly. Use a 229 mm (9/16 inch) socket.

2. Loosen the two bolts that hold the top and bottom of the AC Fuse Assembly to the cabinet frame.

3. Slide the AC Fuse Assembly off the two bolts forward and out of the cabinet.

DC Capacitor Assembly Removal

1. Remove the Inverter Module Assembly.

2. Remove the AC Fuse Assembly.

3. Remove the two clear plastic shields that cover the DC Capacitors.

4. Remove the white neutral bus wires from the two large resistors connected to the frame at the back of the cabinet.

5. Remove the red and black wires from the resistors. The wires locations are labeled. Verify and record the labeling.

6. Remove all DC cables from the positive and negative DC Bus bars.

7. Remove the positive and negative DC bus bars from the DC Bus fuses.

8. Loosen the six bolts that hold the DC Capacitor Assembly to cabinet frame.

9. Slide the DC Capacitor Assembly straight out the front of the cabinet.

Installation

DC Capacitor Assembly Installation

1. Slide the DC Capacitor Assembly straight in the front of the cabinet so that the loosened bolts slide into the corresponding slots in the cabinet frame.

2. Tighten firmly the six bolts that hold the DC Capacitor Assembly to cabinet frame.

3. Attach the positive and negative DC bus bars to the DC Bus fuses.

4. Attach all DC cables to the positive and negative DC Bus bars.

5. Tighten the cable lugs to 54 N·m (40 lb ft).

6. Attach the red and black wires from the resistors.

   The wires locations are labeled.

7. Attach the white neutral bus wires to the two large resistors connected to the frame at the back of the cabinet.

8. Attach the two clear plastic shields that cover the DC Capacitors.

9. Install the AC Fuse Assembly.

10. Install Inverter Module Assembly.

AC Fuse Assembly Installation

1. Slide the AC Fuse Assembly forward onto the two bolts loosened in the cabinet frame.

2. Tighten firmly the two bolts that hold the top and bottom of the AC Fuse Assembly to the cabinet frame.

3. Attach the bolt from the bracket that connects the AC Fuse Assembly to the Inverter Module Assembly, if present. Use a 229 mm (9/16 inch) socket.

Inverter Module Assembly Installation

1. Slide the Inverter Module Assembly straight forward into the cabinet.

2. Attach the bolt that connects the Inverter Module assembly to the AC Fuse Assembly. Use a 229 mm (9/16 inch) socket.

3. Attach the four bolts that connect the Inverter Module Assembly to the DC Capacitor Assembly fuse bus. Use a 229 mm (9/16 inch) deep socket.

4. Tighten the bolts to 61 N·m (45 lb ft).

5. Attach the bolt from the bracket of the Inverter Module Assembly that holds the assembly to the cabinet frame.

6. Attach the toroid wire assembly that is bolted to the bottom of the bracket for the Digital Gate Logic Board.

7. Tie-wrap the cables out of the way.

8. Attach the connectors to the Digital Gate Logic Board. The wires locations are labeled.

9. Attach the clear plastic cover over the Digital Gate Logic Board of the Inverter Module Assembly with three cross head screws.

Inverter Post-Installation Steps

1. Attach the vertical fan plenum over the inverter heatsinks. There are 12 bolts. Use a 178 mm (7/16 inch) socket.

2. Close the DC Disconnect in each of the Flywheel Cabinets. Make sure that the green light is ON before operating the DC Disconnect Switch.

3. Refer to the information in Systems Operation, Testing and Adjusting, RENR7654, "Bringing UPS Online" for bringing the UPS online after work is done to the DC Bus.