Usage:
CONFIDENTIAL TIBU3817-00
TECHNICAL INFORMATION BULLETIN |
March 26, 2003 |
Uninterruptible Power Supply |
UPS 300 (CNJ, CPZ) UPS 301 (CSY) UPS 600 (CTX) UPS 900 (CRY) |
Component Codes: 1418 |
SUBJECT: All Series 300 Uninterruptible Power Supply (UPS) Systems that have a 201-2706 (Power Distribution Board) and a 201-2604 Circuit Board Assembly Circuit Board Assembly (AC Interface Board)
PROBLEM:
Under abnormal conditions, the fuse ratings for the vacuum pump, 190 VAC Power Supply, and the AC Interface Board may be insufficiently sized. These insufficiently sized fuse ratings can result in a fuse opening due to a false condition.
SOLUTION:
In an effort to improve the service reliability of the UPS system, the following preventive maintenance should be performed at the next scheduled maintenance interval.
For exact operational instructions and procedures, refer to the following publications:
RENR2476, Systems Operations, Testing and Adjusting, "UPS250, UPS300, UPS500, UPS750, and UPS900 Uninterruptible Power Supply"
SEBU7464, Operation and Maintenance Manual, "UPS250, UPS300, UPS500, UPS600, UPS750, and UPS900 Uninterruptible Power Supply"
PROCEDURE:
Warning:
When the flywheel is spinning, the following components are energized: the bus, the armature leads, and the flywheel armature fuses. Perform this procedure as quickly as possible. During this procedure, the rotor will be spinning on the bottom bearing.- Place the UPS system in Bypass mode by turning the key switch to the Bypass position.
- Isolate the UPS system from the load by closing the Bypass circuit breaker(s).
- Open the circuit breaker for the Output of the UPS system.
- Open the circuit breaker for the Input of the UPS system.
- Allow the capacitor banks to bleed down for approximately five minutes.
- Locate the 201-2706 Circuit Board Assembly (Power Distribution Board PWA).
- On the PWA Board, locate fuse F1. Remove the currently installed fuse and replace with a 180-6254 Fuse (20 Amp).
- On the PWA Board, locate fuse F2. Remove the currently installed fuse and replace with a 235-5655 Fuse (7 Amp).
- On the PWA Board, locate fuse F3. Remove the currently installed fuse and replace with a 235-5655 Fuse (7 Amp).
- On the PWA Board, locate fuse F7. Remove the currently installed fuse and replace with a 199-5099 Fuse ? Midget (10Amp).
- On the PWA Board, locate fuse F8. Remove the currently installed fuse and replace with a 199-5099 Fuse ? Midget (10Amp).
7. Locate the 201-2604 Circuit Board Assembly (AC Interface (ACI) Board).
- On the ACI Board, locate fuses F1, F2, F3, and F4. Remove the currently installed fuses and replace with 236-4453 Fuses (5 Amp).
8. Close the AC circuit breaker for the Input of the UPS system.
9. Close the AC circuit breaker for the Output of the UPS system.
10. Open the Bypass circuit breaker(s).
11. Return the system On-Line by turning the key switch to the On- Line position.
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