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What's wrong with my garage wiring?

Umm.... I guess I've been a little busy for the last 1.5 years. lol

I have never solved this problem. Today, I ran all new wires and outlet for my welder in the garage. Meter reads 200V(is this too low?) at breaker, outlet, and the the end of the extension cord where the welder plugs in. The welder works everywhere except my garage. It's driving me crazy.

I'm attaching a couple pictures. On is the 100A breaker in a box mounted below my electric meter. This 100A breaker runs to the garage. The other picture is the box in my garage. One other potential issue is the use of 10/2 wire instead of 10/3. Could this be my problem?
 
Hard to tell from the pics but is that aluminum wire?! If it is you need to change it out. I also can't tell how the ground is run. What is the voltage at the top of the breaker that serves the garage box? The one under the electric meter. 200vac is not enough. Minimum should carry is 208vac. 200 tells me you have a problem. Weak ground? Bad wire(s)...connections, etc.
 
10GA is not rated for 100A, 10GA is rated for 30A up to 100' then you would want to use 8GA. I pretty sure you would want to use 2GA wire for 100A.
 
The 10 ga is what is run to your welder, right? Not the main feed coming in?

The top pic is the main box and the second the box in the garage? You have two legs as each breaker is a dual pole. Pretty sure your issue is the wire itself and/or the ground.

Measure each leg for voltage. Put one lead on the wire and the other on ground. Each leg should read 120. This will help to indicate which leg is the problem. If that is aluminum wire you need to pull new copper no matter what. I'd just go ahead and do it myself.
 
"Horseplay" said:
Hard to tell from the pics but is that aluminum wire?! If it is you need to change it out. I also can't tell how the ground is run. What is the voltage at the top of the breaker that serves the garage box? The one under the electric meter. 200vac is not enough. Minimum should carry is 208vac. 200 tells me you have a problem. Weak ground? Bad wire(s)...connections, etc.
Click to expand...

100A breaker.... I was concerned with that 200, also. At some point there has to be a minimum, I assume, or else the device will not operate.
 
"Grabber70Mach" said:
10GA is not rated for 100A, 10GA is rated for 30A up to 100' then you would want to use 8GA. I pretty sure you would want to use 2GA wire for 100A.
Click to expand...

The 10 gauge is only on the outlet and was suggested as the problem to me yesterday. I'm going to try using a larger wire and see how that affects everything. I'm learning the hard way, obviously.
 
"Horseplay" said:
The 10 ga is what is run to your welder, right? Not the main feed coming in?

The top pic is the main box and the second the box in the garage? You have two legs as each breaker is a dual pole. Pretty sure your issue is the wire itself and/or the ground.

Measure each leg for voltage. Put one lead on the wire and the other on ground. Each leg should read 120. This will help to indicate which leg is the problem. If that is aluminum wire you need to pull new copper no matter what. I'd just go ahead and do it myself.
Click to expand...

Right, the 10 gauge is the wire from the breaker box to the outlet. I have larger wire for a cord from the outlet to the welder.

Both legs read 100V. Yes, it is aluminum wire feeding the garage. I've read about aluminum expanding and contracting, causing issues.

I appreciate everyone's help!
 
Does it read 100v one each leg at the top of the main box (house) breaker? I'm guessing those readings cam further down the line. You need to meter it at the source and each point down the line to find your problem. No feed is going to give you 100vac. You have wiring and/or grounding issues.

Again, I highly suggest you pull new wire (including a good ground wire) from source to the garage. Pretty sure your issue is the aluminum wire and ground.
 
I'll have to get back to this in a bit... my grandma passed away. Kind of a blessing though. She has been pretty much incapacitated since she had a massive stroke around 8 years ago. She was 74.

I will check the voltage upstream and at the main breaker in the box as soon as I can. I can't find either one of my meters so I have to borrow one when I need it.

Pulling new wire doesn't sound fun... is this something I need to hire someone to do? As far as I can tell, the wire was properly installed in conduit, but it wouldn't surprise me to learn the jackhole that built the garage ran the wiring wrong. Just another job to add to the To-Do list.

Thanks!
 
Sorry to hear about your grandmother.

Pulling wire won't be too bad provided the old was was run through the conduit properly. You should be able to pull it through by hand.
 
I appreciate your help. It looks like that is my next step. It's unfortunate they placed the box on the far side of the garage away from the house.
 
Since you are most likely rewiring your garage feed, it might make sense to relocate the subpanel within the garage to a more logical/convenient/useful location at the same time. Just sayin'......
 
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