Flyback / snubber diodes

Discussion of the physical aspects
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Jrhaas60
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Flyback / snubber diodes

Post by Jrhaas60 »

I'm using 24vdc solenoids for my glycol valves. I'm thinking I need flyback diodes to protect the relays. Any experienced opinions out there? Thanks
Jrhaas60
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Re: Flyback / snubber diodes

Post by Jrhaas60 »

I thought I would get some response to this. Anyone running 24v dc solenoids who've had relays fail and not know why? I've ordered my diodes and will be adding them either way. Too cheap and easy not to do it and I do believe it will help relay life in my case. Not sure if it's significant at 12v. Cheers.
JonW
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Re: Flyback / snubber diodes

Post by JonW »

Most relay boards come with flyback diodes these days. Are you using individual relays that don't already have the protection?
Jrhaas60
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Re: Flyback / snubber diodes

Post by Jrhaas60 »

I'm using a board from electronic salon like I saw used by many others on this forum. There are no diodes across the output contacts shown in the schematic linked to below for these boards.
https://images-na.ssl-images-amazon.com ... HTDz-L.pdf
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Re: Flyback / snubber diodes

Post by JonW »

A flyback diode is across the coil contacts, not the output contacts. The board you've shown does have a flyback diode on the coil.
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Re: Flyback / snubber diodes

Post by Jrhaas60 »

You need it on both sides for the same reason.
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Re: Flyback / snubber diodes

Post by Jrhaas60 »

You need it on both sides for the same reason.
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Re: Flyback / snubber diodes

Post by Jrhaas60 »

Oops on the double posting.... newbie mistake...
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