Hypertherm 380 Plug

The plug is either a 20 amp 120 volt or a 20 amp 250 volt, depending on which pin is horizontal and which is vertical. See bottom of the page at
Jim Meyer wrote:

Hypertherm, Thermal and Miller all do this and it is just annoying.
Cut the plug off and wire on a standard 110 volt plug. Then make an adapter to go from a 220 v plug to the 110 volt plug.

Is your plug Nema 5-20?

Yes, that's the one. I'm going to take Ernie's advice and just cut the plug off and put a standard 110v plug on it. Then I'll make a pigtail to covert to a 220v.
Thanks Guys, Jim

That is the same plug that was on my Maxstar 140STR. All I did was take a pair of pliers and twist the pole to match the other side. I know that is not the correct way but it worked fine.

That's exactly what the guy at the local Welding Supply store said!
I just couldn't do it. I may be 40 years old, but I can still hear my Dad saying "That's not how you do it. Do it right."
Jim

Quite right. Its there to insure that the welder is not used on a too small 15 amp circuit. Its quite common in machine tools that use more than the normal "appliance" amperage.
My home machine shop is wired with the matching female outlets, which is nothing more than a basic 110 volt duplex receptical, with one slot that can be used either way. The recepticals are a couple bucks at Home Despot or Lowes. All my 110 volt outlets have 20 amp breakers on them and the appropriate sized wiring.
From the above link... Look at the second from the top left, 5-20. The Right one is the one I use, so I can use high ampereage devices anywhere in the shop, and still use regular devices in the same outlet. Ive put them on all my welder extension cords as well. Single Phase 220 with a box on the end with break outs for the various 220 welding connectors and 110vt devices like grinders etc. They fit in the standard duplex box Gunner
"People are more violently opposed to fur than leather, because it is easier to harrass rich women than it is motorcycle gangs." - Bumper Sticker

saying "That's not how you do it. Do it right." That's exactly what the guy at the local Welding Supply store said!

Come to think of it, I bet my Dad doesn't realize I was listening. I'm sure I was the same pig-headed kid to him. I should give him a call and let him know he is haunting me from 3,000 miles away. :-)
Anyway, I didn't cut the end off. I left it on and made two adaptors. One for a standard 110v outlet and one for my normal shop 220v. That way I have 3 possible plugs (including the Nema 5-20 plug that's on it).
I still haven't fired it up yet. I have the Powermax 600 right now and was looking for something a little smaller for light gauge stuff using 110v. Looking at the manual I didn't see anything about the machine operating any different in 110v or 220v. For whatever reason my noodle thought it would cut better & quicker at 220v.
Jim

Though maybe your dad would not be proud of you for plugging a 20 amp machine into a 15 amp receptical :) Seriously, if you do that, put a mark on the amp dial at about 2/3 or even 1/2 it's max range to remind you to not get to aggressive when plugged into 110. I cannot believe that anyone working at a welding shop would suggest such a thing as twisting the horizontal plug! Everyone I've met has been amazingly saftey conscious, but I do live in Ca...
I have this same machine, I made a pigtail to run it off of 220V/30A sockets. I don't think there is any difference in outward performance between 110 and 220 (Assuming you actually have 20A of 100 available), BUT it may actually be better for the machine to run it at 220. The transformers primary winding will run cooler at the lower currents that 220 allows. I have some other 110/220 equipment where using 110 causes the thing to audiably hum because the transformer is bucking from requiring double the current of 220.
Larry
> Come to think of it, I bet my Dad doesn't realize I was listening. I'm sure > I was the same pig-headed kid to him. I should give him a call and let him > know he is haunting me from 3,000 miles away. :-) > > Anyway, I didn't cut the end off. I left it on and made two adaptors. One > for a standard 110v outlet and one for my normal shop 220v. That way I have > 3 possible plugs (including the Nema 5-20 plug that's on it). > > I still haven't fired it up yet. I have the Powermax 600 right now and was > looking for something a little smaller for light gauge stuff using 110v. > Looking at the manual I didn't see anything about the machine operating any > different in 110v or 220v. For whatever reason my noodle thought it would > cut better & quicker at 220v. > > Jim > >
> >>>I just couldn't do it. I may be 40 years old, but I can still hear my > >>>Dad > > saying "That's not how you do it. Do it right." > > Good for you! My father wasn't around to do that for me but I had a boss > > that was a stickler for "if it's worth doing, it's worth doing right" and > > I'm trying to teach my pig-headed 20 year old son the same thing! :-) > > > > Best Regards, > > Keith Marshall > > snipped-for-privacy@progressivelogic.com > > > > "I'm not grown up enough to be so old!" > > > >
> >> That's exactly what the guy at the local Welding Supply store said! > >> > >> I just couldn't do it. I may be 40 years old, but I can still hear my > >> Dad saying "That's not how you do it. Do it right." > >> > >> Jim > >> > >>
> >>> That is the same plug that was on my Maxstar 140STR. All I did was take > >>> a > >>> pair of pliers and twist the pole to match the other side. I know that

That is very true. I will be drawing more current at full tilt than the breaker will allow. I'll just have to play around with it and see what happens. Worse case scenario should be that I trip the breaker. No pain, no foul.
Hmmm, on a similar train of thought. What happens if I plug the machine into the 220 outlet and forget the flip the switch in the back and it is still set to 110? Bad day? Expensive day?
Jim

Hahaha!
Thankfully I don't know anything about that yet! :)
Though I would guess that there is an internal breaker...
Larry

That would be my hope as well. I pray we never find out...
Jim

I hope we do find out and it is a re-setting thermo breaker connected to a relay that drives a warble alarm to be nice to us. Mart> That would be my hope as well. I pray we never find out...

A couple of days ago I sent Hypertherm an email asking them what would happen. So far, no response. When I hear back from them I will post it here.
Hopefully, it is as you describe. Jim

I just received this reply from Hypertherm:
-----Original Message----- From: Morong, Don [mailto: snipped-for-privacy@Hypertherm.com] Sent: Friday, November 12, 2004 08:55 AM To: James Meyer Subject: RE: Powermax 380 power switch
Mr. Meyer, The Powermax380 has a over-voltage protection circuit that should prevent any damage. If the system switch is set for 110V and the machine is plugged into 220V and turned on, a fault light on the front panel will light, indicating an "over-voltage" situation. If the system was set to 220V and plugged into 110V, the same light will illuminate indicating a "under-voltage" situation. The only time there is a possibility of damage is if someone has plugged it into the wrong voltage, see's the fault indicator light, and then tries to flip the voltage selector switch while the system is still turned on. Always turn the system off when changing the voltage selector switch. If you have any other questions or if I can be of any other help to you, please contact me anytime.
Don Morong Technical Marketing Hypertherm Inc 800 643 0030, ext. 1218