I have generally seen that if you go by the Ecap data sheet say: 2000hrs @ 105 degrees C. T
Then if you are running at an Ecap case temp of say 65 degrees C; the MTBF works out to be about 32000hrs; if the case temp is 75 deg C, the MTBF is 16000hrs and so on. MTBF generally applies to 50% of the batch. Caps generally fail as the electrolyte liquid evaporates due to heat, reducing the ripple current capacity and thus going in to an avalanche deterioration mode inverse exponentially. I would recommend you to run a statistical batch in a temperature controlled oven at about the data sheet temperature, for which the manufacturer has provided the life data. ( Also known as accelerated life test). Related info in MIL-STD-105. Arun Kaore EMC Engineer ADI Limited Systems Group Test & Evaluation Centre Forrester Road, St Marys 2760 P O Box: 315, St Marys NSW 1790 Tel: 61 2 9673 8375 Fax: 61 2 9673 8321 Email: kao...@sg.adi-limited.com.au -----Original Message----- From: WOODS, RICHARD [SMTP:wo...@sensormatic.com] <mailto:[SMTP:wo...@sensormatic.com]> Sent: Thursday, 24 June, 1999 5:30 To: 'emc-pstc' Subject: Capacitor Failure Analysis Can you recommend a lab in the USA that can perform failure analysis on an electrolytic capacitor? --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
