KIT-SEAL 2186823 - Caterpillar

CONFIDENTIAL TIBU4272-01
TECHNICAL INFORMATION BULLETIN August 11, 2004
Uninterruptible Power Supply
This Technical Information Bulletin replaces the June 16, 2004 UPS TIB, "UPS system-generated error messages regarding, "Static Switch Thyristor Open" and "Static Switch Timeout A+B-"". Disregard the June 16, 2004 UPS TIB.
UPS 300 (CNJ, CPZ)
UPS 301 (CSY)
UPS 600 (CTX)
UPS 900 (CRY)
UPS 250 (APZ, CNM, BEE)
UPS 500 (CSE)
UPS 750 (CPM)
Component Code: 7451SUBJECT: UPS system-generated error messages regarding, "Static Switch Thyristor Open" and "Static Switch Timeout A+B-"
This document applies to the UPS product equipped with the 199-5096 Static Switch Assembly, the 180-6221 SSI PWA, and the 200-8331 Gating Lead Harness.
PROBLEM:
Service technicians are improperly diagnosing the cause of the following UPS system-generated error messages: "Static Switch Thyristor Open" and "Static Switch Timeout A+B-". This misdiagnosed problem is resulting in improper repairs and invalid Warranty Claims.
SOLUTION:
The "Static Switch Thyristor Open" and/or the "Static Switch Timeout A+B-" error messages indicate a problem with the operation of a Silicon Controlled Rectifier (SCR) in the Static Switch Assembly (199-5096). There are six SCR components within the Static Switch Assembly. Refer to Illustration 1. Each SCR component has an associated Gating Lead wiring harness (200-8331, Illustration 3), which connects the SCR to the Static Switch Interface circuit board (SSI PWA) (180-6221). The typical cause for the "Static Switch Thyristor Open" or the "Static Switch Timeout A+B-" error message has been isolated to the Gating Leads or the Gating Lead connectors. Specifically, the problem has been primarily limited to the mating surface of the Gating Lead socket to the Plug Receptacle pin on the SSI PWA.
This document provides the service technician a proper trouble shooting guideline to determine the cause of the "Static Switch Thyristor Open" or the "Static Switch Timeout A+B-" error message and provide the appropriate corrective action. This trouble shooting guideline is to assist the service technician in locating a Short Circuit, High Impedance, Open Circuit, or Intermittent Circuit within the Static Switch assembly.
Use of this document assumes that the service technician has successfully completed the formal service training program for the CAT UPS Series 300 Product as provided by the Caterpillar Corporate Training Center.
Use of this document also assumes that the service technician has been trained on the usage of special equipment such as meters and oscilloscopes and that these devices are calibrated to a standard recognized and traceable to the National Bureau of Standards.
When using an oscilloscope, only utilize an oscilloscope which provides electrical isolation between each channel and the trigger source. The use of an unapproved oscilloscope could result in equipment damage, de-energizing the load, personal injury, or death.
Hazardous voltages maybe present. Failure to follow appropriate safety procedures could result in personal injury or death.
When the flywheel is spinning, the following components are energized: the bus, the armature leads, and the flywheel armature fuses.
When Uninterruptible Power Supply (UPS) equipment must be in operation to make tests and/or adjustments, high voltage and current are present.
Improper use of test equipment may result in equipment damage, de-energizing the load, personal injury, or death.
When servicing or repairing