I want a relay to turn on a 120V device when another 120V device is turned on.

Unfortunately most relays I've encountered are 12 or 24 volt DC. I could simply slap a power brick in there and get the job done, but is there such a thing as a relay that does this without fiddling around with converting?

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    \$\begingroup\$ Google 120vac coil relay. \$\endgroup\$ Aug 29 '20 at 20:12
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    \$\begingroup\$ Something like this is what you may be looking for. I've a box of them here -- something very much like it, anyway. In my case, I control them with an MCU and either a MOC3023 or else a MOC3063 as this avoids loading down my MCU DC supply with a relay coil. \$\endgroup\$
    – jonk
    Aug 29 '20 at 21:06
  • \$\begingroup\$ To the close-voters: "Does X exist?" and "How can I solve Y?" are on-topic questions, part-number and vendor requests are not. \$\endgroup\$
    – Jasen
    Aug 29 '20 at 23:08
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    \$\begingroup\$ Relays with 120V AC coils should be readily available from electronic distributors such as Mouser, Digikey, Farnell, etc. \$\endgroup\$ Aug 30 '20 at 0:08
  • \$\begingroup\$ There are lots of 120VAC coil relays and contactors (and even SSRs). They tend to be more expensive and use more energy than their DC equivalents. And sometimes they emit objectionable sounds such as hum or buzz at 100/120Hz. \$\endgroup\$ Aug 30 '20 at 5:47

Yes. 110 V AC relays are common in industrial control systems. All the major distributors stock them.


Yes. 120V relays exist, I’ve used them (long ago, when I worked in HVAC controls.)

That said, you could use a 120V-24V transformer (like for a doorbell) to run a lower voltage relay.


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