I found this outlet on the second floor of my apartment.

I thought the plug could be an isolated ground plug, but then why is the connector so weird? And I dont live in a hospital.

Important: I found this plug trying to analyze the fuses in one of my rooms. I'd like to hopefully find there to be ~25A of possible current in this room - right now the fuses are at 20A. So if i could somehow pull a lot of current from this plug that would be dandy.enter image description here

  • Forgot the photo and got a downvote. Sorry
    – mick jagger
    Commented Aug 31, 2019 at 17:12
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    You also forgot to give a country / location and there is none in your user profile.
    – Transistor
    Commented Aug 31, 2019 at 17:12
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    I am the third person calling for you to describe what exactly you are trying to power. There is no such thing as a 120V/25A load, no one builds those because there is no place to plug them in. Last time we had one of these, it turns out he wanted to power 6 servers. He could easily put 3 servers on 1 circuit and 3 servers on another he had available. That never dawned on him, so by keeping his load a secret, he was giving us an XY problem! Commented Aug 31, 2019 at 23:13
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    Oh no, that's a bad design. The two hair dryers will fail very quickly; they're not made for continuous load. However, making heat is cheap, you won't have any trouble making 3000W of heat, just use 240V products or permanently hack/hardwire identical heaters in series. I do that with Chromalox strips all the time. If you really want to do it this way, just use two 120V circuits, every house has 10-20 of them. Commented Sep 1, 2019 at 8:52
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    If you're going to use a 250W bulb, you should consider using an infrared bulb instead of halogen. Doing so is likely to be more efficient, as halogen bulbs are usually designed primarily to provide visible light, with the heat as a quite significant undesired byproduct. That's in contrast with an infrared bulb, which is intended to provide heat with visible light as a byproduct.
    – Makyen
    Commented Sep 1, 2019 at 16:33

2 Answers 2


The formal technical term is Ms. Winky (sockets are female)...

That is a NEMA 6-20. It provides 240V at up to 16 amps continuous. The fuses must be 20A, that is the only size allowed here.

As a general rule, you can never give yourself more power by up-sizing fuses or breakers, so put that idea right out of your head and never consider it again. It's not like we randomly use excessively large wires for no reason. Fuses and breakers are already the max the wires will allow.

There is no neutral here, which means you cannot derive 120V except with a transformer. You cannot take neutral from anywhere else for a variety of reasons. However if the cable supplying this outlet also includes a (capped off) neutral, or if the wires reach this outlet via conduit, an upgrade is possible - ask.

Also as a general rule, any load that requires 25A @ 120V (3000W) is very stupid. That's not how power is done in North America. Common receptacle circuits are 15-20A. The vast majority are 120V (permitting 1440-1920W maximum (80% is the max for a plug-in appliance). However, 240V is well supported, giving 2880-3840W maximum. Therefore: Any appliance that needs 3000W would be manufactured to use 240V.

You are keeping your load a secret, so we have to guess. You say it needs 25 amps (3000W). If it is an array of PCs or other load that is capable of running 120V or 240V, then you are in luck. You can get 4800W (3840W continuous) out of this receptacle. Just get a NEMA 6-15 power strip and cords and you're off to the races (6-15 is more readily available than 6-20).

If your load absolutely requires 120V, then buy a different thing, or get an isolation transformer (not a stepdown transformer) of appropriate size.

  • A 3000W PC is going to be one hell of a gaming rig.
    – stib
    Commented Sep 1, 2019 at 0:15
  • If i live in the US, how exactly is this voltage in my landlord's apartment complex generated? through a transformer in his backyard? Because the AC lines carry 120V here and it's just a normal apartment Commented Sep 1, 2019 at 5:13
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    Every household in the U.S. (that’s connected to the power grid) has both 120 and 240 volts.
    – prl
    Commented Sep 1, 2019 at 6:07
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    @steveantwan power in North America is supplied as 240V with a tap in the middle called "neutral", giving you either 240V, or two "banks" of 120V. This receptacle does not give you access to that tap, so it is 240V only. However it is plenty enough 240V to do whatever you need. Commented Sep 1, 2019 at 8:46
  • Holy sh*t thanks. Google just spits out 120V when i look that up. That's a really cool design and something I never knew Commented Sep 1, 2019 at 14:18

That is a NEMA 6-20, 240 volt 20 amp outlet. It will have two "hot" wires and no neutral. There should be 240 Volts between the two hot wires, and it should be fed by two fuses, one in each hot wire, or by a two-pole breaker.


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