1、Lessons Learned Entry: 0875Lesson Info:a71 Lesson Number: 0875a71 Lesson Date: 2000-02-29a71 Submitting Organization: JSCa71 Submitted by: Larry GreggSubject: Implementation of Sensors and Warning Devices to Detect Out-of-Tolerance Conditions Description of Driving Event: On May 16, 1994, an AMDAHL
2、5995M mainframe 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 po
3、wer outage and 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 cou
4、ld have prevented 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: Malfunctions (including warnings and alarms) on critical equipment and its supporting interfaces
5、 require an appropriate and timely response by trained personnel capable of taking immediate action or countermeasures according to preplanned procedures.Recommendation(s): All operators should be thoroughly trained on all equipment operations and potential malfunctions including troubleshooting pro
6、cedures to clearly define actions to take for malfunctions. In addition, malfunctions that are hazardous to critical equipment or operator health and safety should be defined and “quick response“ procedures developed and trained for these. Operational conditions that are potentially damaging to equi
7、pment should be identified and placards posted on the associated hardware. Sensors should be located such that they will detect the critical operational parameters under all credible malfunction conditions and environments.Provided by IHSNot for ResaleNo reproduction or networking permitted without
8、license from IHS-,-,-Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Administration/Organizationa71 Communication Systemsa71 Computersa
9、71 Configuration Managementa71 Emergency Preparednessa71 Environmenta71 Energya71 Facilitiesa71 Ground Operationsa71 Ground Equipmenta71 Hardwarea71 Industrial Operationsa71 Information Technology/Systemsa71 Occupational Healtha71 Policy & Planninga71 Risk Management/Assessmenta71 Safety & Mission A
10、ssurancea71 Securitya71 Test Articlea71 Test Facilitya71 Test & Verificationa71 Training EquipmentAdditional Info: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-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-,-,-
