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From: Lasse Langwadt <llc@fonz.dk>
Newsgroups: sci.electronics.design
Subject: Re: DC relay latching voltage
Date: Sat, 24 Aug 2024 14:32:06 +0200
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On 8/23/24 21:43, Don Y wrote:
> On 8/23/2024 7:36 AM, John Robertson wrote:
>> I assume you have the normal back diode across the coil for clamping 
>> the ringing voltage.
> If you care about the life of the relay (and how well it "opens"),
> a better approach is to add a zener rated at the coil voltage in
> series with that diode.  The diode, by itself, delays opening of
> the contacts and leads to more opportunities for arcing.  The
> zener speeds up this transition.
> 

or use a fet that is avalanche rated or has build in clamping