Does anyone know what kind of outlet is this one: enter image description here

...and can I safely swap it with this one? enter image description here

Or is there anything power concerns that I should be aware of??

  • 1
    Try to look inside the box at the wires attached to the side of the receptacle. Is one of the wires white? How do you feel about opening up your service panel? Commented Jan 31, 2018 at 6:10

4 Answers 4


Your existing outlet (NEMA 6-20) is used for 240 volts while your USB/outlet (5-15) is designed for 120 volts. Assuming the 6-20 is correctly wired, you cannot just replace it with the USB outlet. As well as supplying the wrong voltage to anything plugged into it, the USB charger that is built in will probably die, possibly violently!

(The key to knowing that it is for 240 volts is that the right-hand slot is horizontal instead of vertical. The T-slot on the left is for 20 amps and can accept either a 6-15 (15 amp) ot 6-20 (20 amp) plug.)

If you want to use the new outlet in that place, you will need to go into your fuse/breaker box and change the wiring to the outlet to 120 volts.

  • what about just replacing it with a normal outlet (no USB)... The room will be a music room and will be having guitar/bass amps and other studio equipment, so the 240V is needed as is to being able to plug the equipment. Commented Feb 1, 2018 at 0:12
  • It is against code and dangerous to put a 120 volt outlet on 240 volts. While what you plug into it may accept a wide range of voltages, someone else might, unknowingly, plug a 120 volt-only device into it and have it blow up in his face.
    – DoxyLover
    Commented Feb 1, 2018 at 0:52
  • So the NEMA 6-20 is always used with 240V outlets? thus any 240V device will have a compatible plug... Commented Feb 1, 2018 at 2:28
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    @BaratierErebusDuHalm 6-20 is the standard 240 volt 20 amp outlet. There’s also the 6-15 and 6-30 for 15 and 30 amps. 5 series is always 120 volts and 6 series is always 240 volts. There’s also the 14 series which adds a neutral to the 6 series for devices that use both 240 and 120 volts. See en.m.wikipedia.org/wiki/NEMA_connector for details.
    – DoxyLover
    Commented Feb 1, 2018 at 2:48
  • BTW, 120 and 240 volts are nominal. They really represent 110-125 and 220-250 volts.
    – DoxyLover
    Commented Feb 1, 2018 at 2:50

You would need a 240v USB outlet.

They are common everywhere but north america, but the issue is getting the US plugs as well. The only places with US plugs and 240 are Japan and Columbia, so if you can find a combo USB outlet for those places it should work without rewiring or using bulky adapters.

If you just want USB (no AC), there's a ton of options because just about any universal or non-us adapter plate will work, and you don't have to match connectors: USB is the same worldwide.


It certainly resembles a standard outlet, doesn't it? It's actually a NEMA 6-20 receptacle made for 240V. I did a quick search for NEMA 6-20 receptacle+USB combos, and found none.

It is probably connected to the service panel with 12-2 cable, black/white/bare wires. It's the same wire you use to hook up normal receptacles. Except the white/black wires both land on a 240V/20A breaker and are both hot. No neutral.

If you just yanked this out and fit a common USB+receptacle combo, it would fry everything you plugged into it.

Inside the panel, it could be rewired to land the white wire on the neutral bar instead of the breaker. The black wire can stay where it is. Once this is done, you must also simultaneously change out the receptacle for the common NEMA 5 type (you know the one) and yeah, you have a picture of a NEMA 5-15+USB one.


Since that outlet is 240V, the easiest solution is to keep the outlet in the wall and use an international adapter that will allow you to use a regular USB power adapter in it. Most USB power adapters will work on a voltage range of 100-240 VAC and a frequency of 50-60 Hz, but verify that your adapter specifies that it works on 240 VAC and 60 Hz before doing this.

Below is an example of the international power adapter that you would need. This will plug into your existing outlet and allow you to use a normal USB power adapter on it as long as you verify that the AC power adapter works on 240 VAC and 60 Hz (which most of them do.)

enter image description here enter image description here


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