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: Andrew Rowland
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?
Subject: Al Electrolytic Capacitors
Reply Posted by: bwd
Date Posted: Tue Aug 10 9:38:46 US/Eastern 2004
Mil –Hdbk-1131A is the guidance document for storage shelf life and reforming procedures for aluminum electrolytic capacitors. The handbook is for guidance only and is not a specification. The information is at the part level, although many military customers are asking about reforming capacitors on units. The handbook says to reform capacitors after a six or ten year storage period. The process for a unit would be to simple take the unit out of storage and operate for several hours so that the full capacitance will be achieved. The same leakage problems for individual parts in storage exist for units in storage. Therefore, reforming of the aluminum electrolytic capacitors is a concern that needs to be addressed as part of the maintenance concept.