SRC Forum - Message Replies
Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and Answers
Topic Posted by: Reliability & Maintainability Forum
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Posted by: Berni
Date posted: Thu Jun 3 2:46:33 US/Eastern 2004
Subject: Part Stress Calculation
When I perform a part stress analysis (MIL 217F2)which electrical condition should I use?
For example, if I have a resistor with a sinusoidal tension applied, how can I compute the actual power dissipation?
Should I use the max or the mean tension?
Subject: Stress Analysis
Reply Posted by: bwd
Date Posted: Wed Jun 9 15:37:04 US/Eastern 2004
The part stress analysis for a resistor is computed by dividing actual power dissipated by rated power. Rated power is the manufacturers specified values and the dissipated is calculated from the circuit design. if you do not have such information, then one should use the part count section of MIL-HDBK-217 as it contains default values for the variables. With regard to the sinusoidal tension, I do not believe that this is significant in the determination of the device failure rate.