Another :rainbow: electrical question

[Sully]

Okay, everyone knows by now I am no electrical genius.

This is the outlet in my garage that is "supposedly" 220, and was run for the previous owner's welder.

It's clearly a different style of recepticle than the 220 plug on my welder. (MM175)


WTF is it?
Can I simply replace it with an appropriate recepticle?
Should I test it in any way, before running the welder off of it?


Yeah,stupid questions, I know. But I know just enough about electricity to respect it's power to burn down my house, that I want to make sure I'm only asking stupid questions, instead of making stupid assumptions and performing stupid acts!

[Sully]

Duhhh, forgot to include the picture. :rolleyes:

[jasonmt]

Looks like a NEMA 10-50R to me which is rated at 50 amps. Could be wired for 125 OR 250V so you should put a meter across the two slanted slots and see if it is 125 or 250V. If it is 250V, check your wiring and breaker to ensure that they are to code and install a NEMA 6-50R for your 175 to plug into. If it is 125V supply you will need a 250V breaker but you should not have to replace any wiring. The 175 only needs 20A so as long as your circuit supplys that things will work out.

http://www.evenheat-kiln.com/technical/recept/650R.gif

http://www.evenheat-kiln.com/technical/recept/1050R.gif

[Buddha's Ghost]

PS: Two legs should be hot (115v each) and the straight one should be ground. Check each slanted one to ground and you should have 115v on each.

[F-Trooper]

that' a dryer receptacle in pic. works fine
for a welder. you can change it to correct
nema configuration for your plug, or change
the plug on your welder, whichever is easier
for you. probably on a 30/50A dp-breaker.
if it's on a 50A breaker, exchange it for a
20/30A or you won't have the protection
you need. if the circuit is marked on your
service panel, you'll know whether it's 110/220v
as the breaker will be either single pole or
double pole. if not, test receptacle as pre-
viously mentioned & narrow it down from
there. if you haven't built that extension
cord yet....just put the dryer plug on one
end & correct recep. for your welder plug
on the other... :idea:

[jasonmt]

that' a dryer receptacle in pic. works fine
for a welder. you can change it to correct
nema configuration for your plug, or change
the plug on your welder, whichever is easier
for you. probably on a 30/50A dp-breaker.
if it's on a 50A breaker, exchange it for a
20/30A or you won't have the protection
you need. if the circuit is marked on your
service panel, you'll know whether it's 110/220v
as the breaker will be either single pole or
double pole. if not, test receptacle as pre-
viously mentioned & narrow it down from
there. if you haven't built that extension
cord yet....just put the dryer plug on one
end & correct recep. for your welder plug
on the other... :idea:


F-Trooper brought up something not explictly explained except for "check your wiring and breaker to ensure that they are to code". If it is a 50A breaker you will HAVE to change it to a smaller breaker in order to comply with NEC article 630:

"Welders
Arc Welders must be protected by a fuse rated at not more than
200% of the rated primary current. The fuse protecting the supply
conductor can serve as the welder protection, if the fuse is rated at
not more than 200% of I1max or the welder rated primary current
[630.12(A)]."

So for a Miller 175 with a input of 19.5A a 50A breaker would not be in compliance with the NEC. I have 2 circuits ran in my garage with 6 guage wire and 6-50R boxes. One has a 30A breaker for my smaller machines and the other has a 50A breaker for the larger machines.

I would switch the box to a 6-50R as they are pretty much the "standard" welder plug that is used by ITW and Lincoln.