I am buying this house, and the seller has added a 220V outlet to the
garage already in addition to the dryer. Which is nice because I
plan to run a 220V welder or compressor soon..

I did notice he had a honda power generator with a short piece of 220V
cord sitting near the outlet.. which I am assume it plugs into the
outlet.. but I can't figure out what he was doing with it, and I
forgot to ask. Could he have powered the house via the generator
during black outs?

But my question is, will I be able to use this outlet for a 220V
welder?
Does a welder require a different plug than the dryer?

I would bet he was using the plug for back feeding the house but I am sure
there will be a dozen people jumpinhg in to say how illegal that is (It is).
You are really going to have to determine where this 240v receptacle comes
from, what size breaker it is and what size wire. Then you can figure out if it
will serve the welder you want. You may still end up changing the receptacle
(depending on the welder) but if the wire and breaker are OK it is no big deal.

jj3000 wrote:
I am buying this house, and the seller has added a 220V outlet to the
garage already in addition to the dryer. Which is nice because I
plan to run a 220V welder or compressor soon..

I did notice he had a honda power generator with a short piece of 220V
cord sitting near the outlet.. which I am assume it plugs into the
outlet.. but I can't figure out what he was doing with it, and I
forgot to ask. Could he have powered the house via the generator
during black outs?

But my question is, will I be able to use this outlet for a 220V
welder?
Does a welder require a different plug than the dryer?


A welder usually uses a 6-50R receptical (but they frequently don't have
a plug and you put your own plug on to match your receptical.) 10-50R is
pretty common even though it's technically incorrect.)

That generator receptical could be any of a half-dozen different
configurations based on your description, and either 30A or 50A.
If that circuit goes all the way back to a main electrical panel (either
*the* main panel, or a subpanel in a detached garage wired as a service
entrance), then you can safely use the grounded wire to ground your
welder even if the plug is wrong. If the supply wires are fed by a
subpanel, you need to make sure the grounded wire is connect to the
ground bus and not the neutral bus, and its insulation color becomes
more important (should be green).

If you have a 50A welder and only a 30A circuit, you can still use it
but you will not be able to run the welder at its maximum amperage
settings unless you replace the breaker with a 50A. There is a special
provision in the electrical code that allows the overcurrent protection
(breaker) for a welder to be sized according to welder's amperage
rating, and the circuit wires to be sized according to the duty cycle --
i.e. 10 ga copper conductors on a 50A breaker to supply a welder with a
50A draw and a 20% duty cycle.

Best regards,
Bob