Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and AnswersTopic Posted by: Reliability & Maintainability Forum (email@example.com )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Original Message:Posted by: Destin LeBlanc (Destin.LeBlanc@craneaerospace.com )
Date posted: Fri Dec 12 20:10:30 US/Eastern 2003
Subject: Resistor short circuit failure modes/FMD-97
In RAC's Failure Mode/Mechanism Distributions 1997 (FMD-97), the failure mode "Shorted" is given for Resistors (I'm specifically looking at "Resistor, Fixed, Wirewound" here). My EEs are telling me this is completely impossible, but every FMEA I've ever seen has considered "Resistor Shorted" as a possible failure mode. Unfortunately, many many web searches on the possible combinations of keywords here have yielded almost no results; I've seen as many people saying shorted resistors are a failure to consider as saying that it is impossible (and I can count them each on one hand). So I'm hoping somebody can shed some more light on this situation. Are the failures listed in FMD-97 only manufacturing defects (ie, not a result of an operational situation)? Is it possible to say for sure that, if you drive too much current through a resistor, it *won't* fail shorted? [I would assume knowledge of the physical construction of resistors would tell us that.] Thanks!