REG NASA-LLIS-0443--1992 Lessons Learned - High Voltage Electric Circuits.pdf

1、Lessons Learned Entry: 0443Lesson Info:a71 Lesson Number: 0443a71 Lesson Date: 1992-11-16a71 Submitting Organization: LERCa71 Submitted by: G. MichalsonSubject: High Voltage Electric Circuits Description of Driving Event: During the removal of power to a transformer prior to it being serviced, an ac

2、cidental 2400 Volt line to ground short circuit was created resulting in minor injury to a technician and minor hardware damage. The major contributing factor to this mishap was the use of a drawing that was not adequately checked after additions and changes had been made to the system. The secondar

3、y factor was that the technician did not test the voltage on the line side of the potential transformer compartment to verify that the bus was in fact de-energized.Lesson(s) Learned: Personnel injury and hardware damage can result if inaccurate drawings are used for preparation of power switching in

4、structions.Recommendation(s): Assure that approved drawings (verified, accurate and complete) are used to prepare power switching instructions or any maintenance procedure.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AProvided by IHSNot for ResaleNo reproduction or

5、 networking permitted without license from IHS-,-,-Mission Directorate(s): N/AAdditional Key Phrase(s): a71 Configuration Managementa71 Energya71 Logisticsa71 Safety & Mission AssuranceAdditional Info: Approval Info: a71 Approval Date: 1996-09-13a71 Approval Name: Sell Jamesa71 Approval Organization: 501-4a71 Approval Phone Number: 216-433-8618Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-