UPS 750 Uninterruptible Power Supply Caterpillar

DC Capacitor Module

Illustration 1	g03692544
DC capacitor module (1) Holes for mounting bolts (2) DC capacitors

The DC capacitor module is located in the center of the FPU cabinet. There are 4 DC capacitor modules. One module is attached to each flywheel inverter/utility inverter sets. The DC capacitor module provides energy storage from the inverter modules.

Note: When servicing the DC capacitor modules, any DC capacitor modules located in front of the DC capacitor module requiring attention must be removed. Replacement capacitors must be installed.

Removal

The DC capacitor module is heavy. Exercise caution when removing the last bolt so the assembly does not fall and damage components or injure personnel.

1. Open the flywheel cabinet doors 90 degrees or more. Refer to Illustration 2.

2. Remove the ground strap that is attached to the door.

3. Remove all cable ties on the wiring from the top 24 inches of the flywheel cabinet frame.

4. Remove the 1/4 inch bolts that hold the DC capacitor module shield in place. Set the bolts aside. The bolts are to be reused.

5. Remove DC capacitor module shield. Set the shield aside. The shield is to be reused.

6. Disconnect the DC (+) and DC (-) cables from bottom right of DC capacitor module.

7. Remove the 16 1.5 UF capacitors that connect the DC capacitor module to the FDG and UGD modules.

8. Remove the four bolts and hardware that connect the module to the center plate.

9. Install the DC capacitor/inverter module lifting tool by performing the following steps.
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   Illustration 2	g03692570
   (5) Lifting tool in stowed position

   1. Remove the bolts and washers that secure the lifting tool (5) in the stowed position on top of the flywheel cabinet. Refer to Illustration 2. Be sure to save the bolts and washers. The bolts and washers are used to attach the beam to the brackets and the brackets to the flywheel cabinet frame.

   2. Remove the lifting tool brackets and beam from the top of flywheel cabinet.

   3. Attach the lifting tool assembly to the left and right upright brackets of the frame. Use the 1/4 inch nuts that are provided with the tool. Refer to Illustration 3.
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      Illustration 3	g03692571
      (6) Left and right lifting tool brackets installed

      Note: The left and right bracket threaded studs must be installed on the rail with the top-most stud in the hole. Install the bracket 2-1/16 inches down from the corner gusset of the left and right upright front rails. Refer to Illustration 4.

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      Illustration 4	g06063622
      (7) Lifting tool bracket threaded studs

   4. Attach the lifting tool beam to the top flanges of the left and right upright brackets.

      Note: There are four threaded studs on the top of each upright bracket. The flanges of the lifting tool beam are held in place by these threaded studs.

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      Illustration 5	g06063673
      (8) Block and tackle assembly (9) Lifting tool beam (10) Left and right lifting tool brackets (11) Lifting tool hook

   5. Attach the lifting tool block and tackle (8) to the lifting tool assembly frame. Refer to Illustration 5.

      Note: The lifting tool cross-beam (9) must be parallel to top rail of the enclosure.

   6. Attach the block and tackle lifting hook (11) to the DC capacitor module handle.

   7. Use the locking pin to secure the lifting tool hook in place in the module handle DC Cap Module Handle.

10. Remove the two bolts that connect the bottom of the module to the frame of the flywheel cabinet.

11. Remove the two bolts that connect the top of the module to the frame of the flywheel cabinet.

12. Slide the module forward and down to remove the old assembly.

Installation

1. Install the DC capacitor/inverter module lifting tool block and tackle on the new module.

2. Move new module into place.

3. Install the four bolts and hardware that connect the module to the center plate.

4. Install the two bolts that connect the top of module to the frame of the flywheel cabinet.

5. Install the 16 1.5 UF capacitors that connect the DC capacitor module to the FDG and the UGD modules.

6. Connect the DC (+) and the DC (-) cables from the bottom right of the DC capacitor module.

7. Ensure that the installation is complete correctly.

8. Remove the lifting tool and stow properly.

9. Close and lock the cabinet doors.

10. Start up the system. Refer to the Systems Operation, Test and Adjust, UENR4695, "System Startup" section.

Extended Runtime Cabinet (EXRC) DC Capacitor Module

Illustration 6	g06050530
Left side of Extended Runtime Cabinet (EXRC) with outside and inside panels removed (19) DC Capacitor module location

The EXRC capacitor module is located behind the front baffle of the EXRC. The EXRC fans must be removed before removing the capacitor module.

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

Removal and Installation

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Illustration 7	g06050692
DC Capacitor Module

1. Remove the "EXRC" fan assemblies. Refer to Systems Operation, Test and Adjust, UENR4695, "Cooling Fan" for proper procedure.

   Note: The DC Capacitor module is below the opening and bolted to the right bulkhead as you face the front of the EXRC.

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   Illustration 8	g06050645
   Battery capacitor and fuse wiring

2. Disconnect all wires connected to capacitors and ceramic resistors. Refer to Illustration 8

3. Retain all hardware.

4. Remove neutral, negative, and positive bus bars from the top of the DC cap module.
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   Illustration 9	g06050731
   (20) DC Capacitor container mounting bolts

5. Remove and retain the three bolts (20) securing the capacitor to the right panel.

6. Remove the case. Lift the case up and out of the EXRC.

7. Move to a suitable work area.
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   Illustration 10	g06050764
   (21) DC Capacitor module top (22) Mounting screws for the capacitor module top

8. Remove module case top (21). Loosen and remove the mounting screws (22).
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   Illustration 11	g06051060
   (23) Nylon nuts securing capacitors in capacitor module

9. Identify and remove any non-functioning capacitors. On the bottom of the case, remove the nylon nuts (23) securing the non-functioning capacitors.
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   Illustration 12	g06051084
   Top view of capacitors in DC capacitor module

10. Replace the capacitors. Reference Illustration 12 for the proper orientation.

11. Replace the top of the capacitor case.

12. Reinstall the capacitor case on the right panel.

13. Reattach the wires that were removed earlier.

14. Reinstall the fan assemblies. Refer to Systems Operation, Test and Adjust, UENR4695, "Cooling Fan" for the proper procedure.

15. Replace any other components removed earlier.

16. Check all connections.

17. Prepare the UPS and EXRC for operation.

18. Return the system to service.

Front and Rear Booster and DC Capacitor Assembly Overview

Illustration 13	g06051140
Front view of EXRC Booster LEG Module Assembly (24) Rear Booster Module (25) EXRC DC Capacitors (26) Front Booster Module (27) Bus Terminals (two on each side) (28) DC Bus Assembly (29) Fuses (1000 VAC, 1250 A) (30) Capacitors - 1.5 μF, 1200 VDC (14 with 7 on each side) (31) IGBT Common Bus

Illustration 14	g06051194
Rear view of EXRC Booster LEG Module Assembly (24) Rear Booster Module (25) EXRC DC Capacitors (26) Front Booster Module (32) Front Booster Module Shroud (33) Negative Booster Input (34) Nylon Nuts (35) Rear Booster Module Shroud

The front and rear booster module assemblies are shown in Illustration 13.

Front Booster Module

Illustration 15	g06058717
Front Booster Module

Illustration 16	g06058838
(36) 3/8 inch hex head bolt (37) Negative 2, 4-0 cables (38) Negative 3, 4-0 cable

Servicing the front booster module requires replacing the entire front module. To replace the front booster module, refer to the following steps.

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

Removal

1. Remove the 3/8 inch bolt, washers, and nut securing the cable lugs to the IGBT common bus.

2. Remove the negative cables from the IGBT common bus.

3. Remove the communication and power cable connectors from the Gate Driver board. Refer to the following list:

   J1-1 - Top front

   J25-1 - Bottom front

   J2-1 - Bottom front

   J3-1 - Bottom front

4. Remove the seven 1/4 inch bolts securing the top of the front booster module to the overhead mounting baffle.

5. Remove the six 1/4 inch bolts securing the bottom of the front booster module to the bottom mounting baffle.

6. Remove the 1/4 inch bolts at the top and bottom of the front booster module. These bolts secure the module to the upper and lower DC capacitor booster brackets.

7. Slide the front booster module out of the EXRC.

   Note: The front booster module weighs approximately 29 kg (65 lb).

8. Use the lifting tool to lift the module up and out of the unit.

9. Lower the module to the floor or another appropriate work surface.

Installation

1. Unpack and inspect the replacement module.

2. Install lifting handle with hardware provided.

3. Use lifting tool to lift the module up and into the unit.

4. Slide the front booster module into the EXRC and toward the DC capacitor module.

5. Insert and hand tighten the 1/4 inch bolts at the top and bottom of the front booster module. These bolts secure the module to the upper and lower DC capacitor booster brackets.

6. Insert and tighten the six 1/4 inch bolts securing the bottom of the front booster module to the bottom mounting baffle.

7. Insert and tighten the seven 1/4 inch bolts securing the front booster module top to the overhead mounting baffle.

8. Plug in the communication and power cable connectors from the Gate Driver Board. Refer to the list seen in Step 3.

9. Replace the negative cables on the IGBT common bus.

10. Replace the 3/8th bolt, washers, and nuts securing the cable lugs to the IGBT common bus.

11. Torque all bolts to the proper torque specifications.

12. Ensure that all connectors are secure on Gate Driver board.

13. Ensure that there is no leftover hardware.

Rear Booster Module

Illustration 17	g06059294
Rear Booster Module (39) Remove DC bus from these locations (40) Disconnect cables and remove

Illustration 18	g06059322
(41) Gate Driver Board Cable Hardware (42) Gate Driver Board cables

Servicing the rear booster module requires replacing the entire module.

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

Note: The Rear Booster Module weighs approximately 29 kg (65 lb).

Removal

1. Remove the 3/8 inch bolt, washers, and nut securing the cable lugs to the IGBT common bus.

2. Remove the negative cables from the IGBT common bus.

3. Remove the communication and power cable connectors from the Gate Driver board. Refer to the following list.

   J1-1 - Bottom rear

   J25-1 - Top rear

   J2-1 - Top rear

   J3-1 - Top rear

   Note: The connectors are at the rear most side of the Gate Driver board against the cabinet sheet metal.

4. Remove the seven 1/4 inch bolts securing the top of the Rear Booster Module to the overhead mounting baffle.

5. Remove the six 1/4 inch bolts securing the bottom of the Rear Booster Module to the bottom mounting baffle.

6. The 1/4 inch bolts at the top and bottom secure the Rear Booster Module to the upper and lower DC capacitor booster brackets. Remove the securing bolts.

7. Slide the Rear Booster Module out of the EXRC.

8. Use the lifting tool to life the module up and out of the unit.

9. Lower the module to the floor or another appropriate work surface.

Installation

1. Unpack and inspect the replacement module.

2. Use the lifting tool to lift the module up and into the unit.

3. Slide the rear booster module in and toward the DC capacitor module.

4. Insert and hand tighten the 1/4 inch bolts at the top and bottom of the Rear Booster Module. These bolts secure the module to the upper and lower DC capacitor booster brackets.

5. Insert and tighten the six 1/4 inch bolts securing the Rear Booster Module bottom to the bottom mounting baffle.

6. Insert and tighten the seven 1/4 inch bolts securing Rear Booster Module top to the overhead mounting baffle.

7. Plug in the communication and power cable connectors from the Gate Driver board. Refer to the list in Step 3.

8. Connect the negative cables to the IGBT common bus.

9. Torque all bolts to the proper torque specifications.

10. Ensure that all connectors are secure on the Gate Driver Board.

11. Ensure that there is no leftover hardware.

Capacitor (DC Booster)

Illustration 19	g06059450
DC Capacitor Booster Module

Servicing the DC capacitor booster requires replacing the entire module.

Removal

1. Ensure that the front booster module has been removed.
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   Illustration 20	g06062997
   (43) DC capacitor module (44) Remove and retain hardware

2. Remove the bolts securing the DC capacitor module to the 750 VAC fuse on the right. Refer to Illustration 20.

3. Remove the bolts securing the DC capacitor module to the lower mounting baffle.

4. Remove the bolts securing the DC capacitor module to the upper mounting baffle.

5. Attach lifting straps.

6. Using the hoist, lift the DC capacitor module out of the EXRC cabinet.

7. Lower and place on the floor or an appropriate work surface.

Installation

1. Attach the lifting straps to the DC capacitor module.

2. Secure the hoist to the DC capacitor module.

3. Using the hoist, lift the DC capacitor module to where the base is level with the lower mounting baffle in the EXRC cabinet.

4. Slide the unit into the EXRC.

5. Locate the base over the mounting holes in the upper and lower mounting baffle.

6. Insert and finger tighten the bolts securing the DC capacitor module to the lower mounting.

7. Insert and finger tighten the bolts securing the DC capacitor module to the upper mounting baffle.

8. Insert and finger tighten the bolts securing the DC capacitor module to the fuses. These bolts secure the module to the 750 VAC fuse on the right and the two 1200 VAC fuses on the left.

9. Tighten all bolts.

10. Check all work.