Welder Outlet

[472scout]

So I go to fire up my welder and nothing. Breaker is in ON position, but I cycle it a few times regardless. Plug in my other welder and still nothing.

Put the DVM across the 2 hot lines at the outlet and I'm only getting 90VAC. Hmmm, it's only about a 6 ft run between the outlet and garage subpanel.

Shut off power to the subpanel, pull the cover, and check connections. All tight. No signs of heat damage or arcing.

Check resistance between both hot lines at the outlet and get infinity. Also get infinity from each hot line to ground or neutral. So no shorts.

Flip the breaker on and check resistance across each line and get zero ohms.

Pull the breaker out of the panel and there is grease, I guess antioxidant, on the terminals.

What next?

 

[TEXINTEG]

Try putting the breaker in one notch down on the panel. You have to split the 220 so it isn't on the same circuit. I don't know of a better way to explain this. sorry. I had the same problem.

 

[Vegaman_Dan]

Definitely test the bus rails to ensure you've got the full voltage to the breakers. Disconnect the wires from the breakers so you're only testing the breakers. Check output voltage. I suspect you've got one bad breaker there.

 

[NUTTSGT]

You said subpanel, correct ? Are you getting the proper current to the subpanel ? Is one of the hot legs coming out to the garage bad ?

Just like looking for a leak, just keep looking farther up stream for the source of the problem.

 

[wyliesdiesels]

Next step after checking voltage at outlet is to check voltage at breaker lugs(obviously with breaker on). If reading is wrong, next step is to check line lugs of subpanel...

 

[472scout]

Try putting the breaker in one notch down on the panel. You have to split the 220 so it isn't on the same circuit. I don't know of a better way to explain this. sorry. I had the same problem.

Yes, one side to red and the other to black.

Definitely test the bus rails to ensure you've got the full voltage to the breakers. Disconnect the wires from the breakers so you're only testing the breakers. Check output voltage. I suspect you've got one bad breaker there.

You said subpanel, correct ? Are you getting the proper current to the subpanel ? Is one of the hot legs coming out to the garage bad ?

Just like looking for a leak, just keep looking farther up stream for the source of the problem.

I just powered up the subpanel with the cover off and got 245VAC across lines.

Put the ohm meter on the breaker again, this time with it on the bench, and still get zero ohms. So seems ok.

I guess I'll pull the outlet just to be sure before I drive the 10 miles to get a new breaker.

 

[NUTTSGT]

Yes, one side to red and the other to black.





I just powered up the subpanel with the cover off and got 245VAC across lines.

Put the ohm meter on the breaker again, this time with it on the bench, and still get zero ohms. So seems ok.

I guess I'll pull the outlet just to be sure before I drive the 10 miles to get a new breaker.

You have any other double pole breakers in the breaker box to swap into that position to rule out the 50amp breaker ?

If not, do you have a Square D box in the house you can swap one from ? That's why I always recommend putting the same style box in the garage as you have in the house.

 

[wyliesdiesels]

Yes, one side to red and the other to black.





I just powered up the subpanel with the cover off and got 245VAC across lines.

Put the ohm meter on the breaker again, this time with it on the bench, and still get zero ohms. So seems ok.

I guess I'll pull the outlet just to be sure before I drive the 10 miles to get a new breaker.

How are u testing the breaker? from lug to stab?

 

[472scout]

Looks like the breaker in the main panel that feeds the subpanel may be bad (intermittent). Earlier I had 245VAC across the red/black in the subpanel. Now after flipping the main breaker a few times after running different tests I have ~100VAC across the lines at the subpanel. 122VAC on the black and 18VAC on the red with the other meter lead on the ground bus. I pulled out the breaker for the welder and no change.

It kind of makes sense that the main breaker would be the one to go out. It's going on 10 years old, versus 2 years for the subpanel breaker, and we've had a bunch of lightning this past month.

You have any other double pole breakers in the breaker box to swap into that position to rule out the 50amp breaker ?

.

Unfortunately, I don't.

How are u testing the breaker? from lug to stab?

Yep.

 

[wyliesdiesels]

Have u tested the voltage at the feeder breaker lugs?

What brand breaker?

 

[472scout]

I haven't had the cover off the main panel yet. It's a Siemens type QP.

 

[472scout]

Ok, it's fixed. Thanks for the help, all. One side of the 60A breaker in the main panel was bad. On the bench it would ohm out ok about 4 out of 5 times. I guess an intermittent breaker is not that uncommon, but it had me a mite bewildered. I bought the same $10 breaker as that's all they had at the HD. Are arc welders hard on breakers?

 

[NUTTSGT]

Glad to hear you got it fixed, get to welding now.

 

[wyliesdiesels]

Ok, it's fixed. Thanks for the help, all. One side of the 60A breaker in the main panel was bad. On the bench it would ohm out ok about 4 out of 5 times. I guess an intermittent breaker is not that uncommon, but it had me a mite bewildered. I bought the same $10 breaker as that's all they had at the HD. Are arc welders hard on breakers?

not usually. How old is the breaker?