Usage:
CONFIDENTIAL TIBU3883-00
TECHNICAL INFORMATION BULLETIN |
June 25, 2003 |
Uninterruptible Power Supply |
UPS 300 (CNJ, CPZ) UPS 301 (CSY) UPS 600 (CTX) UPS 900 (CRY) |
Component Codes: 4480 |
SUBJECT: All Series 300 Uninterruptible Power Supply (UPS) Systems that have either a 180-6221 Static Switch Interface, 201-2606 Bypass Cabinet Controller or a 229-8307 Board Assembly (ZigZag Controller)
PROBLEM:
The Gating Leads of the 200-8331 Cable (Thyristor) interconnect the following components to their associated devices: Static Switch Interface, the Bypass Cabinet Controller, and the ZigZag (Neutral Static Switch) Controller. It has been determined that the Gating leads of the 200-8331 Cable (Thyristor) may not be properly secured.
Some of the symptomatic conditions associated with this issue are as follows:
Static Switch:
A reoccurring Event Log entry stating:
"ERROR! Static Switch Thyristor Open."
The UPSView telemetry tiles may display the following:
The DC Offset will have "high" readings.
The Input Current may display an abnormally low reading on one phase while the other two phases have normal readings.
The UPS may "discharge" excessively when subjected to a load 50 percent or greater.
Static Bypass and Neutral Static Switch:
Errors associated with these two devices are difficult to detect due to the duration and frequency of operation.
SOLUTION:
In an effort to improve the service reliability of the UPS system, the following preventive maintenance examination 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
Personal injury or death can result from high voltage.
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 is required to be energized in order to perform test measurements and calibration procedures, high voltage and high current are present. Exercise extreme caution.
Improper test equipment can fail and present a high voltage shock hazard to its user.
Make sure that the testing equipment is designed for and correctly operated for the high voltage and high current tests that are being made.
When servicing or repairing UPS equipment, make sure all capacitors are discharged.
During this procedure, the rotor will be spinning on the bottom bearing. Keep hands, feet, and clothing away from all moving parts.
The preventive maintenance examination procedure is listed below. Before performing the procedure, determine whether the UPS is experiencing any of the aforementioned symptoms (Static Switch, Static Bypass, or Neutral Static Switch).
You can confirm if the UPS is experiencing any of the aforementioned symptoms by one of the following two methods:
- Retrieving a current "Event Log" from the UPS.
- Reviewing the various telemetry tiles when you are connected directly to the UPS with your laptop computer.
In the event you confirm that the UPS is experiencing a one of the symptomatic conditions, you will need to proceed as follows.
- 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.
- The following is the preventive maintenance examination procedure:
- Upon successful completion of the examination, place the UPS back On-Line utilizing the current RENR2476 Systems Operation Testing and Adjusting Manual and SEBU7464 Operation and Maintenance Manual procedures.
- For further assistance, call Griffin Product Support at 770-233-3911.
a. Disconnect the Gating Lead Connector(s) 200-8331 and examine the connector sockets.
b. Determine whether they are properly installed and firmly secured.
c. If the connector(s) exhibit any signs of excessive "flaring" which will prohibit the connector from making a secure connection, the Gating Lead Connector should be replaced.
d. Caution should be exercised whenever a technician places a test probe (i.e. VOM Probe end) into the Gating Lead Connector sockets, that they do not induce "flaring" of the Gating Lead Connector terminals.
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