# 12V Electric Electronic Relays



## Phaeton (18 Mar 2021)

Need to have some changeover relays to get my kitcar on matching switches for the test, not really need but would make it look nicer, anyway trawling ebay for the relays dodging all the Chinese sellers who claim to be in the UK came across a seller in Leeds, but he has 2 different types










The obvious difference is the resistor across the coil, what is it's purpose & do I need it?


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## newfhouse (18 Mar 2021)

Phaeton said:


> Need to have some changeover relays to get my kitcar on matching switches for the test, not really need but would make it look nicer, anyway trawling ebay for the relays dodging all the Chinese sellers who claim to be in the UK came across a seller in Leeds, but he has 2 different types
> 
> View attachment 579187
> 
> ...


Using a resistor is a polarity agnostic alternative to using a back-EMF prevention diode in the same place. If you’re using real switches rather than fancy electronics then you don’t really need it, but it won’t do any harm either.


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## Phaeton (18 Mar 2021)

So as they are the same price, I'll go for the resistor version, Thank you


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## figbat (18 Mar 2021)

I usually go to 12 Volt Planet for this kind of thing. So far, so good. Not sure how cost competitive they are but they can’t be too bad or I wouldn’t have used them!


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## Phaeton (18 Mar 2021)

figbat said:


> I usually go to 12 Volt Planet for this kind of thing. So far, so good. Not sure how cost competitive they are but they can’t be too bad or I wouldn’t have used them!


Like them, link saved for the future


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