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Forum: Reliability & Maintainability Questions and Answers

Topic: Reliability & Maintainability Questions and Answers

Topic Posted by: Reliability & Maintainability Forum (src_forum@alionscience.com )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998

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Original Message:

Posted by: Jean-Marie CLOAREC (jean-marie.cloarec@ligeron.com )
Organization:LIGERON S.A.
Date posted: Fri Oct 25 10:11:26 US/Eastern 2002
Subject: Negative temperature
Message:
How calculate failure rate when ambiant temperature is negative. MIL HDBK 217 + RDF + ... are based on temperature from 0C to ... but when temperature is for example -25C ?


Reply:

Subject: Negative Temps
Reply Posted by: Joe Dzekevich (jdzekevich )
Organization: Raytheon
Date Posted: Tue Oct 29 12:52:09 US/Eastern 2002
Message:
You must use an absolute temp scale. If you look into most standards, they use degrees K for their Pi-T formulas. Hopefully the reliability prediction softeare you are using can handle a negative number if it requires temps in centrigrade. Otherwise, you must calculate Pi-T yourself and then overide it in your program.


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