Topband
[Top] [All Lists]

TopBand: Remote Beverage Switching

To: <topband@contesting.com>
Subject: TopBand: Remote Beverage Switching
From: lkayser@rideau.net (Larry Kayser)
Date: Sun, 29 Dec 1996 17:52:09 -0500 (EST)
Bill wrote about back emf from a relay as the voltage is removed...
>I once ran some scope tests on suppressed vs. unsuppressed relay coil
>transients.  The results were startling - an unsuppressed 28 vdc
>hermetically sealed aircraft relay can easily generate 600 volt spikes
>at the coil terminals.  The addition of a back-biased diode across the
>coil nearly eliminates the spike.

This is not without a penalty however.  The relay will be MUCH MUCH slower
in release time with the diode across the coil terminals.

Larry
va3lk / wa3zia


--
FAQ on WWW:               http://www.contesting.com/topband.html
Submissions:              topband@contesting.com
Administrative requests:  topband-REQUEST@contesting.com
Sponsored by Akorn Access, Inc & KM9P

<Prev in Thread] Current Thread [Next in Thread>