A friend of mine asked a good question, why is that most SMT capacitor specs call out for a maximum heating rate at SMT of 2-4 C/sec but the same specs allow a temperature delta at wave soldering of 100-125 C? In case of wave, the time between preheat and soldering causes a heating rate in excess of the SMT heating rates. But it is OK to subject the part to the wave solder but not SMT using those heating and cooling rates?

I never could recall a logical explanation. Called several capacitor manufacturer's and they seemed to dance around the question.

Any information would be helpful




______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/ContentPage.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------