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What kind of relay do I need to switch 20A 120VAC using a 12V coil?
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Marty_L:
Basically I want to be able to turn on a space heater remotely. The one I have uses 13 amps but I wanted to be able to switch the maximum that one of them could pull which I figure is 15 amps through a regular wall plug, so I figure I should get a relay that can handle more than that just so its not operating at its max. So I was thinking I would get a relay that can switch about 20 amps 120V (AC from a US home) and I wanted to do it with 5-12V DC but really any low-ish DC voltage would work if 5-12V is not a reasonable ask or if it is cost prohibitive. But I'm having trouble finding a relay that meets those specs, I'm sure I'm just searching using the wrong terms but all I get are relays with 120VAC coils or else all they can switch is 12VDC (automotive relays). I'm hoping that somebody has some experience with this and can tell me what device I'm looking for or what I'm doing wrong when I'm searching. I've tried a BUNCH of different terms on a lot of different sites, some of the terms:
12v coil 120vac 20a load relay
12v coil 120vac 20a contacts relay
12v coil 120vac 20a contact rating relay
12v coil 20a switching current relay
12v coil 20a relay
20amp relay

those are the more complete terms, I've use lots of others and partials of those and the others. Oh and SPDT would be nice but I can kinda work with whatever on that front. Thats all the relevant information I can think of, let me know if I have left something out and thank you in advance for your help.
Tom45:
A search at Digikey for in-stock 12 VDC coil, 15 amp contacts relay gives 37 choices.

An example is a Potter and Brumfield relay (Digikey PB329-ND)
Marty_L:
So on digikey, if I search out of all products it returned 0 results, if I changed it to only search in Relays it returns 2,700 and some results, not sure I understand how that works but I guess I don't have to :)

Don't I want 20 amp or should I just go with 15 amps? I've read your not supposed to operate things at their max ratings or it greatly reduces its life. Plus since its going to be operating in a separate room possibly while I'm sleeping and its a large load, I figured I should stay well within the limits. I'm gonna put a fuse inline with it but still... But I'm open to new information.
Siwastaja:
Ratings are difficult; case-by-case. Sometimes you can run continuously at maximum rating no problem whatsoever, with built-in safety margins on specs. Sometimes the manufacturer is outright lying (not limited to Aliexpress sellers; reputable large Western companies do this as well); or there is a strong enough tradition of lying so that people don't even consider it lying but "just the way it is" (like the voltage ratings on tantalum capacitors).

For relays? There is no generic rule. But, when switching mains voltage, definitely pick a relay with third party safety approval markings. Check that the stardard they are tested against is relevant; these should be safe at maximum load, it's the intended use for such relays.

For me, Digikey shows 162 products:
https://www.digikey.com/products/en/relays/power-relays-over-2-amps/188?k=&pkeyword=&sv=0&pv1411=80&pv1411=184&pv1411=88&pv1411=47&pv1411=48&pv1411=58&pv1411=177&pv1411=66&pv1411=165&pv1411=94&pv1411=52&pv1411=63&pv1411=57&pv1411=65&pv1411=39&pv1411=59&pv1411=60&pv1411=152&pv1411=148&pv1411=147&sf=1&FV=ffe000bc%2C120007c%2C1200002%2C120001b%2Cmu100A%7C1410%2Cmu120A%7C1410%2Cmu150A%7C1410%2Cmu200A%7C1410%2Cmu20A%7C1410%2Cmu21A%7C1410%2Cmu25A%7C1410%2Cmu26A%7C1410%2Cmu30A%7C1410%2Cmu31A%7C1410%2Cmu32A%7C1410%2Cmu33A%7C1410%2Cmu35A%7C1410%2Cmu400A%7C1410%2Cmu40A%7C1410%2Cmu48A%7C1410%2Cmu50A%7C1410%2Cmu60A%7C1410%2Cmu90A%7C1410&quantity=&ColumnSort=0&page=1&stock=1&pageSize=25

But do note that relays are sometimes difficult - even dangerous - to shop because multiple different products with different ratings tend to be "multiplexed" in a single datasheet, with confusing and long part numbers, sometimes without explicit tables about what is available and what the actual specs are; hence, the workers at distributors like Digikey often get the specs wrong! Be extra careful with the part numbering so you know you are looking at the correct numbers.

One lucky thing is that your heater is a nice resistive load, so inrush current, or reactive voltage spikes and sparking are not going to be problems.
IanB:
Possibly you don't want a relay, but a "contactor"? Try searching for contactors instead of relays and see what turns up.
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