PRODUCT IMPROVEMENT PROGRAM FOR INSTALLING NOMEX INSULATORS ON CERTAIN 1500IC UNINTERRUPTIBLE POWER SUPPLIES BETWEEN THE DC BUS AND THE SNUBBER CAPACITORS OF THE FLYWHEEL INVERTERS
Caterpillar’s obligations under this Service Letter are subject to, and shall not apply in contravention of, the laws, rules, regulations, directives, ordinances, orders, or statutes of the United States, or of any other applicable jurisdiction, without recourse or liability with respect to Caterpillar.
This Program must be administered as soon as possible. When reporting the repair, use "PI32481" as the Part Number and "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description code. Exception: If the repair is done after failure, use "PI32481" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.
The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.
|The nomex insulators need to be installed on certain 1500iC Uninterruptible Power Supplies. The existing air gap between the DC bus and the snubber capacitors can allow arcing to occur resulting in the failure of the flywheel inverters and possibly the utility inverters.|
|In order to allow equitable parts availability to all participating dealers, please limit your initial parts order to not exceed 45% of dealership population. This is an initial order recommendation only, and the ultimate responsibility for ordering the total number of parts needed to satisfy the program lies with the dealer.
|Remove the flywheel inverters to add four pieces of the nomex insulators between the DC bus and the snubber capacitors.|
|Owners in the following countries will receive the attached Owner Notification:
SERVICE CLAIM ALLOWANCES
|NOTE: This is a 20.0-hour job|
|Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.|
|MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.|
|EXAMPLE COPY OF OWNER NOTIFICATION
3240 Arrow Drive
Anywhere, YZ 99999
PRIORITY - PRODUCT IMPROVEMENT PROGRAM FOR INSTALLING NOMEX INSULATORS ON CERTAIN 1500IC UNINTERRUPTIBLE POWER SUPPLIES BETWEEN THE DC BUS AND THE SNUBBER CAPACITORS OF THE FLYWHEEL INVERTERS
MODELS INVOLVED - UPS1500iC
Dear Cat Product Owner:
Nomex Insulators need to be installed on the products listed below. The existing Inverter can arc between the DC bus and snubber capacitors. You will not be charged for the service performed.
Contact your local Cat dealer immediately to schedule this service. The dealer will advise you of the time required to complete this service.
If you are no longer the owner of this product(s), please contact your local Cat dealer so that our records can be updated. Please refer the dealer to their Service Letter dated 29Apr2015 when scheduling this service.
We regret the inconvenience this may cause you, but urge you to have this service performed as soon as possible to prevent unscheduled downtime.
Attached to 29Apr2015 Service Letter
|Refer to Systems Operation, Testing and Adjusting, "Internal Component Preremoval Steps (Flywheel Cabinet)" in order to shut down the system and gain access to internal components.
Note: The module for the Field Coil Driver (1) needs to be removed in order to gain access to the module for the Flywheel Inverter.
|1. Remove the assembly for the Field Coil Driver. Refer to Systems Operation, Testing and Adjusting, "Field Coil Driver".
2. Disconnect the input cable from the right side of the module (1).
3. Disconnect the "18 AWG Red/Black" (J2) wires from the module (1).
4. Disconnect the ribbon cable (J1) from the module (1).
5. Remove the two mounting bolts from the positive connection of the DC bus.
6. Remove the two mounting bolts from the negative connection of the DC bus.
7. Loosen the two mounting bolts at the top of the assembly for the heat sink.
The module for the Flywheel inverter is heavy. Exercise caution upon removing the last bolt of the assembly in order to not damage components.
8. Remove the module (1) from the assembly.
|Nomex Insulator Installation
1. Insert four pieces of the 469-9079 Nomex Paper insulator between the DC bus terminals on the Snubber Capacitors.
1. Reinstall the assembly in the cabinet.
2. Install the two mounting bolts for the negative connection of the DC bus. Tighten the bolts to 11.3 N.m (100 lb in).
3. Install the two mounting bolts for the positive connection of the DC bus. Tighten the bolts to 11.3 N.m (100 lb in)
4. Install the two mounting bolts at the top of the assembly for the heat sink. Tighten the bolts to 4.5 N.m (40 lb in).
5. Connect the ribbon cable (J1) to the module (1).
6. Connect the input cable to the right side of the module (1). Tighten the bolt to 34 N.m (25 lb ft).
7. Connect the "18 AWG Reb/Black" (J2) wires to the module (1).
8. Install the assembly for the field coil driver. Refer to Systems Operation, Testing and Adjusting, "Field Coil Driver".
9. Energize the system.