1、Lessons Learned Entry: 0227Lesson Info:a71 Lesson Number: 0227a71 Lesson Date: 1993-06-21a71 Submitting Organization: LERCa71 Submitted by: S. PapellSubject: Air Compressors Description of Driving Event: A 500 HP service air compressor stayed engaged after a stop command was issued from the central
2、control dispatcher after a test run. The motor came to an abrupt halt and started to burn, causing extensive damage. The primary damage occurred to the compressor motor as the coils were burned. Damage also occurred to the starter in the form of blown fuses and burned contacts.The cause of the misha
3、p was a direct result of an inadvertently bent follower arm on the starter. When the central control dispatcher commanded the control circuitry off, the DC field was turned off but the starter stayed engaged. The angle of the bent follower arm allowed it to fall behind the walking beam assembly prev
4、enting the starter from disengaging. The running of the motor out of synchronism without field exitation caused overheating of the cage windings to the point where the motor started to burn.Lesson(s) Learned: Mechanical controls on Brown-Boveri air compressor starter assemblies can become damaged, l
5、eading to extensive fire damage to the compressor motor.Recommendation(s): Remove follower arm and walking beam assemblies from Brown-Boveri starters and use indicating lights to establish contactor status.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for ResaleNo reproduction
6、or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Hardwarea71 Industrial OperationsAdditional Info: Approval Info: a71 Approval Date: 1994-04-19a71 Approval Name: Maria Havenhilla71 Approval Organization: LERC/EBASa71 Approval Phone Number: 216-977-1483Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
