1、Lessons Learned Entry: 1756Lesson Info:a71 Lesson Number: 1756a71 Lesson Date: 2006-07-7a71 Submitting Organization: JPLa71 Submitted by: : Kenneth Ericksona71 POC Name: Albert Whittleseya71 POC Email: Albert.C.Whittleseyjpl.nasa.gova71 POC Phone: 818-354-3496Subject: EMC Test Configuration per MIL-
2、STD May Fry Switch-Mode Power Supply Abstract: EMC testing (CS101 or CS01/02) configured in accordance with commonly used engineering standards may result in input power line oscillations, causing an overvoltage condition and damaging flight hardware. Consider the consequences of switch-mode power s
3、upply negative input impedance in the design of EMC conducted susceptibility tests, and ensure that EMC test requirements and procedures include warnings and safeguards against input power line oscillations.Description of Driving Event: Information in this section of the lesson learned is controlled
4、 under the International Traffic in Arms Regulations (“ITAR“) by the U.S. Department of State. If you are authorized to review the content, a copy can be obtained from David Oberhettinger at the Jet Propulsion Laboratory.Lesson(s) Learned: EMC testing performed on switch mode power supplies in accor
5、dance with MIL-STD-461 and MIL-STD-462 may result in input power line oscillations that may cause an overvoltage condition and damage flight hardware. Many EMC test organizations may be unaware that these commonly used standards do not include warnings or safeguards to prevent such oscillations.Reco
6、mmendation(s): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Consider the consequences of switch-mode power supply negative input impedance in EMC test design, and ensure that EMC test requirements and procedures include appropriate warnings and sa
7、feguards against input power line oscillations. Determine whether the commercial EMC test equipment features a DC voltage-stabilizing CS01 test fixture as depicted in Reference (6).Evidence of Recurrence Control Effectiveness: JPL opened Preventive Action Notice (PAN) No. 1468 on July 7, 2006 to ini
8、tiate and document appropriate Laboratory-wide action on the above recommendations.Documents Related to Lesson: NPD 8700.1, NASA Policy for Safety and Mission Success, Rev. C, October 18, 2002Mission Directorate(s): a71 Sciencea71 Exploration SystemsAdditional Key Phrase(s): N/A Additional Info: a71 Project: Microwave Limb Soundera71 Year of Occurrence: 2000Approval Info: a71 Approval Date: 2007-02-01a71 Approval Name: ghendersona71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
