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: Bob Valerius
Organization:Northrop-Grumman Oceanic Systems
Date posted: Fri Jun 4 14:06:30 US/Eastern 2004
Subject: Solid State Relays
Hi. I was looking through RAC's 1991 Failure Mode/Mechanism Distribution Guide. On page 2-23 relays are said to have failed by a spurious trip 26% of the time. Should I assume that is for electro-mechanical relays and is not applicable to solid state relays (SSR), so that a spurious trip of an SSR is extremely unlikely? Thanks for the help.
Subject: Relay Failure Modes
Reply Posted by: bwd
Date Posted: Wed Jun 9 15:00:30 US/Eastern 2004
The data in FMD-91 for relays is for electro-mechanical relays and the mode of spurious tripping would not be applicable to solid state devices. FMD-97 has a section on solid state relays and the failure modes are: corrosion, degradation, open, out of specification, workmanship, induced and fatigue.