1、Lessons Learned Entry: 0874Lesson Info:a71 Lesson Number: 0874a71 Lesson Date: 2000-02-29a71 Submitting Organization: JSCa71 Submitted by: Larry GreggSubject: Quality Inspection of Maintenance Work Performed on Critical Equipment Description of Driving Event: On May 16, 1994, an AMDAHL 5995M mainfra
2、me computer overheated at approximately 8:20 AM in the Software Production Facility (SPF) in Building 30 at JSC. Physical damage to the computer due to this overheat was estimated at $669,000. This overheat occurred due to an inadvertent miswiring of a circuit breaker after a routine power outage an
3、d maintenance of the breaker. The quality inspection failed to check for the proper rewiring of the circuit breaker. The miswiring caused a phase rotation of the power, which in turn caused fans cooling the AMDAHL 2550 to turn backwards. Power isolation and monitoring equipment that could have preve
4、nted any impact from the phase rotation was not properly utilized. This led to insufficient cooling of the AMDAHL 2550 which resulted in the overheat and subsequent damage.Lesson(s) Learned: All operations and maintenance on critical equipment and its supporting interfaces (e.g., power, cooling) sho
5、uld be subject to a quality inspection by an inspector who understands the work done and who verifies the work is done correctly.Recommendation(s): Quality inspection procedures and training should be developed to match the specific maintenance work being accomplished on critical equipment and its s
6、upporting interfaces.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics Resear
7、chAdditional Key Phrase(s): a71 Communication Systemsa71 Computersa71 Configuration Managementa71 Environmenta71 Energya71 Facilitiesa71 Ground Operationsa71 Ground Equipmenta71 Hardwarea71 Human Resources & Educationa71 Industrial Operationsa71 Information Technology/Systemsa71 Policy & Planninga71
8、 Spacecrafta71 Test Articlea71 Test Facilitya71 Test & Verificationa71 Training EquipmentAdditional Info: Approval Info: a71 Approval Date: 2000-04-11a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
