Forum: Reliability & Maintainability Questions and Answers
Posted by: Mats C
Date posted: Thu Aug 12 10:53:30 US/Eastern 2004
Subject: reliability prediction software market
What softwares are on the market for prediction MTBF ?, I am only interested to use for electronics circuits with component librarys ? thanks in advance Mats
Posted by: Andrew Rowland (email@example.com )
Date posted: Mon Aug 2 11:48:21 US/Eastern 2004
The guidance provided in MIL-HDBK-1131A appears to be intended for capacitors being stored as replacement parts. What is the practice for aluminum electrolytic capacitors that are in storage as part of a larger assembly? For example, if I am storing switching DC power supplies as spares, how would I apply (or how do others apply) the guidance in MIL-HDBK-1131A to the capacitors used in the power supplies?
Posted by: Benjamin (firstname.lastname@example.org )
Date posted: Wed Jul 7 5:57:12 US/Eastern 2004
Subject: Tests : HALT, HASS, Qualification
I'm a french student and I work on the HALT (Highly Accelerated Life Test). I have two questions : --> what sort of informations give the HALT tests to start creating the HASS tests ? (specifications, etc.) --> if the HALT tests were realised, what is the development of the Qualification tests (life test during 2000hours, etc.) ? Are they completely removed or just simplified (less hours, stress less rugged, etc.) ? Very many thanks. Benjamin
Posted by: Brett Roundy (email@example.com )
Date posted: Thu Jul 1 13:19:50 US/Eastern 2004
Subject: Failure Modes/Mechanisms in FMD-97
Why does the FMD-97 contain both Failure Modes and Failure Mechanisms?
I am performing a FMECA for a customer using Relex 7.7 and the built-in FMD-97 to define the Failure Modes and I noticed that it includes both Modes (such as short, open, etc.) and Mechanisms (electrical overstress, lead damage, etc.). Aren't Mechanisms usually addressed once the Modes have been sorted by criticality? Thank you.
Posted by: Andrew Rowland (firstname.lastname@example.org )
Date posted: Thu Jun 17 16:06:05 US/Eastern 2004
If anyone has experience with MIL-STD-2173, I am curious about the equation for acceptable failure probability found on page 47. This equation uses 0.5 failures in the numerator. Is there a basis for 0.5 and, if so, what is it?