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Relays and How They're Rated

Relays and How They're Rated

Relays and How They're Rated

(OP)
Hey everyone,

I was looking into getting relays for my circuit, and was hoping you could help. Here's what I want to do:

I need to use an AC power source (a typical wall socket) to power a DC solenoid valve (which has a 24 V rating) AND its AC controller (which has a 120 V rating). That's the way things are set up, good or bad as they are, and I'm supposed to find a way to make it work without spending a lot of money.

I'd like the controller to switch the solenoid valve on and off (that's what its there for), despite the fact that both parts use a different type of current. I figured a good way to wire them in the same circuit would be to use relay switches. This would be a cheaper way to do this versus a transformer, especially since I already have a DC source available (a 120 VAC to 24 VDC converter) for the solenoid valve, and also because my max current will be around 2.5 A, and most affordable transformers have a much lower current rating.

Any thoughts? Would I just get a 5-pin relay with a control voltage rated to 120 VAC? I'd connect my AC source to the relay's control coil, and my DC source / solenoid valve to two of the other contacts (common and N.O.), right?

RE: Relays and How They're Rated

Using a 115 VAC relay with contacts rated for you 2.5 A inductive current (or better) sounds like it would work from what you described.

Or, if your 'converter' you mentioned doesn't power anything else, you could use a 115 VAC relay with AC rated contacts of about an amp to turn the converter on and off (which would turn the solenoid on and off). This had the advantage that you can probably find a usable relay lots of places, including maybe Home Depot or a A/C supply house, or maybe even the maintainence department where you work.

RE: Relays and How They're Rated

Sounds like your on the money

RE: Relays and How They're Rated

I cringe at the thought of switching both AC and DC with the same relay. I would just switch the 120 V relay controller if that is feasible.
respectfully

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