Can someone identify this plug?

plug socket

It came on an older radial-arm saw. Can I replace the plug with a NEMA equivalent that will fit in a regular socket? Not sure where it'll go, but all the locations I'm considering would be easy to put in a new breaker and run a line if it needs either 240V, or higher amperage.

Nameplate: Nameplate

If I'm reading this correctly I can open up the wiring, connect as directed for 115V and then I just need a 10 amp, 60Hz, single-phase circuit - ie. normal wall outlet.


  • 1
    Any model # or motor ratings on the saw? Because it isn't just which type of plug/socket but also making sure it is the right size circuit - too big and it's not safe, too small and it will trip frequently. Jan 19 '21 at 0:12
  • 2
    Yes, can you get us a photo of the nameplate on the saw's motor please, as well as more angles of the plug? Jan 19 '21 at 0:12
  • You see them on construction sights a lot used so the cord don't get yanked out of the receptacle.
    – ojait
    Jan 19 '21 at 0:47
  • 1
    My guess is that plug is pre-dates adoption of nema locking standards because none of the blades have a kick on the ground. But really what it is isn't important, you need to match the voltage and amp rating of the tool to the appropriate configuration. So (as ThreePhaseEel asked) a photo of nameplate would be great! Jan 19 '21 at 1:49
  • 1
    Since you have the opportunity to run new wiring, I'd strongly recommend you leave your saw wired for 240v operation. It will run much better at 240v than it will at 120v. "Everyone" says so!
    – FreeMan
    Jan 19 '21 at 18:48

That is a twist-lock-style plug used with receptacles like this:

enter image description here

Receptacles are still available - I have no idea if it's code-allowed to use them, they're not at all common in my experience.

I would also be inclined to replace the plug for use with a normal common socket. Check the electrical ratings on the equipment for how many volts and amps it uses. These twist-lock receptacles I found go from 120V/15A up to 220V/20A so what's safe and proper would depend on your device/appliance.

  • 3
    Twist-locks are fine by Code still (and I believe required in a few exceptional circumstances) Jan 19 '21 at 1:27
  • 1
    It doesn't have the kink/bend inward, which is why I was thrown when looking at the twist-locks. They all seem to have that on one of the legs.
    – Alex
    Jan 19 '21 at 2:10
  • @Alex Probably a legacy plug, like this one ourbungalows2ndcentury.files.wordpress.com/2016/12/… Jan 19 '21 at 2:27

Twist locks are a level above standard receptacles. There are 120v and 277v models the ground lug is on the opposite side of the ground blade I don’t see the fold but they are still indexed by width so they can’t be plugged in wrong. 4750 is 277v,, 4700 120v 15 amp. To convert to a standard duplex is fine like a 5362 receptacle and a 5266 cord cap would replace the twist lock if it is wired for 120v (I just happened to be in front of my plug bin)


I would expect to apply a 125% rating to the nameplate as a motor requirement, and NEC Table 210.21(B)(3) limits 15A plugs to twelve amps. I would use a nema 5-20 (20A/120v) or preferably a nema 6-15 (15A/240v) plug and receptacle.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.