UPS 750 Uninterruptible Power Supply Caterpillar

Illustration 1	g03693687
(1) Vertical back fan assembly (2) Horizontal back fan assembly (3) Horizontal front fan assembly (4) Front plate (5) Vertical front fan assembly

There are eight fans in the flywheel cabinet. Four fans, (2) and (3), are in a horizontal position and located above the flywheel. There are four fans, (1) and (5), in a vertical position and are located on the left side panel of the flywheel cabinet. Each fan has an alarm that signals the fan interface board if any problems occur.

Horizontal Fans

Horizontal Fan 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 de-energized before removal steps can be performed.

2. Remove the 17 bolts from front plate.

3. Remove the six bolts that attach the front horizontal fans (3), to the flywheel cabinet.

4. Unplug the power cables and the sensing cables from each fan.

5. Slide the assembly forward to remove from the flywheel cabinet.

6. Remove front fan assembly.

7. Remove the two bolts that connect the back fans (2) to the flywheel cabinet.

8. Unplug the power cables and the sensing cables from each fan.

9. Slide the assembly forward to remove from the flywheel cabinet.

10. Remove back fan assembly.

Horizontal Fan Installation

1. Slide the back fan assembly (2) into the flywheel cabinet along the metal guide rails.

2. Plug the fan power and sensing cables into the fan assembly.

3. Tighten the two bolts that mount the fan assembly to the flywheel cabinet.

4. Slide front fan assembly (3) into the flywheel cabinet along the metal guide rails.

5. Plug the fan power and sensing cables into the fan assembly.

6. Tighten the six bolts that mount the fan assembly to the flywheel cabinet.

7. Mount the front plate to the flywheel cabinet with the 17 bolts that were removed earlier in the procedure.

Vertical Fans

Vertical Fan 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.

2. Remove the 12 bolts that connect the door panel to the flywheel cabinet.

3. Remove the left door of the flywheel cabinet.

4. Remove the 19 bolts from the front plate.

5. Remove the front plate.

6. Remove the three bolts that connect the front fan assembly (5) to the flywheel cabinet.

7. Unplug the power cables and the sensing cables from each fan.

8. Slide the assembly forward to remove from the flywheel cabinet.

9. Remove the front fan assembly from the flywheel cabinet.

10. Remove the two bolts that connect the back fan assembly (1) to the flywheel cabinet.

11. Unplug the power cables and the sensing cables from each fan.

12. Slide the assembly forward to remove from the flywheel cabinet.

13. Remove the back fan assembly.

Vertical Fan Installation

1. Slide the back fan assembly (1) into the flywheel cabinet along metal guide rails.

2. Plug the fan power and sensing cables into fan assembly.

3. Tighten the two bolts that mount the fan assembly to the flywheel cabinet.

4. Slide the front fan assembly (5) into the flywheel cabinet along metal guide rails.

5. Plug the fan power cable and sensing cable into fan assembly.

6. Tighten the three bolts that connect the fan assembly to the flywheel cabinet.

7. Install the front plate. Secure the front plate to the flywheel cabinet with 19 bolts.

8. Install the left door of the flywheel cabinet with 12 bolts.

Fan Interface Board

Illustration 2	g03693693
(10) Fan interface board location

Illustration 3	g03693694
PWA fan interface board (FWI)

The fan interface board (10) is located behind the left door panel of the flywheel cabinet. The FWI controls fan speed and shows fan faults.

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.

2. Disconnect J1 through J8, J11, and J13 connectors. The connectors are labeled to identify the correct location on the board. Verify that each connector has a label and is legible.

3. Remove the screw from the right, top corner of the board.

4. Disconnect the 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 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. Position the board in the cabinet over the white stand-offs that are connected to the panel.

2. Push the board, gently and evenly, onto all the stand-offs simultaneously. Make sure all stand-offs are locked in place.

3. Install the mounting screw on the right, top corner of the board.

4. Plug in J1 through J8, J11, and J13 wire connectors into the correct connectors on the board. Check the labels on each connector for proper placement.

Extended Runtime Cabinet (EXRC) Fan

Illustration 4	g06049848
(11) Inverter fan location

The following sections describe the service procedures for the Extended Runtime Cabinet (EXRC) fans.

EXRC Fan Removal

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

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

2. Remove and retain the ten bolts from the inverter fan cover.
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   Illustration 5	g06049911
   (12) Fan motor brackets (13) Fans (14) Fan tray

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   Illustration 6	g06049950
   (15) Fan housing retaining screws (16) Fan tray mounting screw locations

3. Remove and retain the two bolts (16) connecting the fan assembly mounting tray (14) to the EXRC cabinet.

4. Unplug the fan power and sensing cables from the front fan assembly.

5. Slide assembly forward to access power and sensing cables from back fan assembly.

6. Disconnect power and sensing cables from the back fan assembly

7. Slide assembly forward and remove from the EXRC cabinet.

8. Remove the fan housing. Remove and retain the screws (15) holding the fan housing in position on the fan assembly mounting tray (14).

9. Remove the housing with attached fan bracket (12) and the fan (13) from the fan assembly mounting tray.
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   Illustration 7	g06049993
   (17) Fan bracket mounting screws

10. Remove and retain the fan bracket mounting screws (17). Remove the fan motor bracket (12) from the fan housing by removing and retaining hardware.
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    Illustration 8	g06050010
    (18) Fan cap bracket securing bolt

11. Remove the bolt (18) securing the fan cap bracket to the fan. Remove and retain hardware.

12. The fan is ready to be replaced.

EXRC Fan Installation

1. Mount the fan cap bracket (18) with the retained hardware. Refer to Illustration 8.

2. Place the fan (13) in the fan housing.

3. Place and secure the fan motor bracket on the fan housing with the retained hardware. Refer to Illustration 7.

4. Place and secure the fan housing bracket to the fan assembly mounting tray (14) with the mounting screws (15). Refer to Illustration 6.

5. Partially slide the fan assembly mounting tray into the EXRC cabinet.

6. Connect access power and sensing cables to the fans.

7. Slide the fan assembly mounting tray (14) into the cabinet on the two rails.

8. Secure the fan assembly mounting tray (14) with the two mounting bolts (16). Refer to Illustration 6.

9. Replace the inverter fan cover. Refer to Illustration 4.

10. Secure the ten mounting bolts into the inverter fan cover.

11. Ensure that all other components removed earlier are secured.

12. Check all connections.

13. Prepare the UPS and EXRC for operation.

14. Return the system to service.