electrical plug/motor advice

[Dean Chapel]

My powermatic edge sander's motor is rated 20/10 amps. It was switched over to 220, and has a 15 amp plug on it now from the previous owner. Is that the right plug, or should it have a 20 amp plug, or something else? TIA

[John K Jordan]

My powermatic edge sander's motor is rated 20/10 amps. It was switched over to 220, and has a 15 amp plug on it now from the previous owner. Is that the right plug, or should it have a 20 amp plug, or something else? TIA

If by "20/10 amps" they mean 20 amps at 110v and 10 amps at 220 volts single phase and it is wired for 220 volts that plug sounds perfect. That is, if you have the proper 220 receptacle you can connect it to.

[Bill Dufour]

If by "20/10 amps" they mean 20 amps at 110v and 10 amps at 220 volts single phase and it is wired for 220 volts that plug sounds perfect. That is, if you have the proper 220 receptacle you can connect it to.

Good advice here but, look at the cost of a matching receptacle vs switching to some other style. Some times it is cheaper to buy a plug and receptacle rather then just the receptacle for some odd ball plug. Also a good idea to settle on one or two standards for you shop. But make it a standard that you can buy locally or all over ebay.
Bill

[Mike Cutler]

Yep, it's fine. I have them on my table saw and band saw.
Receptacles that accept both a 15amp, plug and a 20 amp plug, are pretty normal. All of my 240 receptacles can accept either. ( The 240/30 amp twist lock being the exception.)

[Lee Schierer]

I don't think the electrical code allows a 120 volt plug or receptacle to be wired in a 240 volt circuit. They make 240 volt twist lock plus and recepatacles for a reason. Using a receptacle intended for 120 volt applications to supply 240 volts is a disaster waiting to happen when someone unknowingly plugs in a 120 volt device. Using a 120 volt plug on a 240 volt motor is also asking for trouble if someone plugs it into a 120 volt outlet.

[Jim Becker]

As Lee suggests, the specific terminations have to be 240v rated/types--which will not fit in 120v terminations physically, but a 15 amp setup is fine for the machine to be running on 240v with its 10 amp rating. For practical purposes, however, most folks put in 240v 20a (or 30a) circuits for woodworking machinery and you can certainly use 20a rated 240v terminations for your tool. In this manner, you're not creating a "special" 15a only connection that confines it to that one tool. And again, you cannot use a 120v termination on a 240v tool, so if the original owner was doing that, change the plug!

[John K Jordan]

...And again, you cannot use a 120v termination on a 240v tool, so if the original owner was doing that, change the plug!

For questions like this, to clarify what is actually attached to the tool and the available receptacle a photo or two is worth a thousand or two words and might save a lot of speculation and misunderstanding. :)

(Hey, do you realize that if a picture is worth 1000 words a word then is worth a milli-picture? Ha!)

[Art Mann]

I don't think the electrical code allows a 120 volt plug or receptacle to be wired in a 240 volt circuit. They make 240 volt twist lock plus and recepatacles for a reason. Using a receptacle intended for 120 volt applications to supply 240 volts is a disaster waiting to happen when someone unknowingly plugs in a 120 volt device. Using a 120 volt plug on a 240 volt motor is also asking for trouble if someone plugs it into a 120 volt outlet.

240V plugs and receptacles that aren't twist lock are common. They come in 15A or 20A sizes. This may be what the original poster was referring to. They look similar to 120V plugs but one of the blades is rotated 90 degrees. I use them in my shop and they work fine. I don't like twist lock precisely because they won't pull out easily if you trip over the wire.

[Mike Cutler]

I don't think the electrical code allows a 120 volt plug or receptacle to be wired in a 240 volt circuit. They make 240 volt twist lock plus and recepatacles for a reason. Using a receptacle intended for 120 volt applications to supply 240 volts is a disaster waiting to happen when someone unknowingly plugs in a 120 volt device. Using a 120 volt plug on a 240 volt motor is also asking for trouble if someone plugs it into a 120 volt outlet.

Lee
The code definitely does not allow you to use 120vac receptacle for 240vac use.
If your post is a response to mine, then that tells me that I wasn't clear in my response.
All of the 240 rated receptacles I have in my shop are 6-20R's They can accept either a 15 amp, or a 20 amp, 240 rated plug. 6-15P, or 6-20P., respectively. The only exception being the 30 amp, 240vac, L630R, receptacle I use for my air compressor.

[Ed Edwards]

:confused:375601

I don't know how to enlarge the image, sorry Ed

[John K Jordan]

:confused:375601

I don't know how to enlarge the image, sorry Ed

Ed, clicking on the thumbnail will display it large. If you want it large inline in your message, you can first upload it to a personal album then insert the image from there.

But one problem with this chart is it doesn't tell what the voltages are. This one might be more useful, full-sized chart in this downloadable PDF (easier to read):
http://www.interpower.com/ic/designers/designing-for-export/guides-and-charts/non-locking-nema-configurations.pdf

375606

For locking plug configurations, search for NEMA locking plug chart


JKJ