Power supply troubleshooting help

[James Eric]

My flux core welder has a jerky wire feed problem but a friend with the same make and model does not have the same problem. Yesterday we tried his welder at my shop and it had the same problem. When he returned home his welder acted normal again. We think the problem is the electrical service in my barn. My barn is fed by 3 wire service. It has a disconnect where it enters the barn and a 100amp breaker panel in the shop area that services the outlets, lights, welder, and compressor. I do not perform electrical service but I need to identify the problem so that I can hire someone to fix it right.

Any ideas on what would cause this situation?

Thanks,

James

 

[Ed of all trades]

I guess that it could be your service but the odds are against it. It sounds like the feed rollers are not adjusted or the liner is either kinked or dirty. I know that it looks like the service is the problem but things are not always what they seem. Check the amount of pressure on the feed rolls. Hold the gun out straight from the machine and see how it works. If you have to check the service use a multimeter and check each leg at your plug in. Ben there done that, and often it don't make sense. But I bet your problem is in the machine. Ed

 

[Mysfyt]

Check ALL your wiring connections starting at the breaker box. Willing to bet somewhere along the line you have a loose connection. These show up when there is a significant load on the circuit, such as a welder. If you're not familiar with electrical, get some help! Done wrong can lead to death!

 

[FredH]

A Good Electrician Would be able to Diagnose the issue likely within a few minutes by simply using several different meters / tools . If you tell them
/ describe the problem as you did above , they would be able to narrow their focus to only a certain area , i.e. that specific circuit , etc.. .

Are We talking 110/120 welder or 220/240 welder ? If 110/120 , Are ALL outlets fed by the same Breaker ? If Not , Switch outlets . Would Eliminate wire from box to outlet . If they are all off the same breaker , try going to a outlet on opposite side of shop .

Some thing to Also consider is Your Ground . Insufficient Ground will play Heck stuff , especially high power stuff .

Honestly Though , If you are not sure about electrical work and will have to hire some one , You won't pay them hardly anymore to diagnose the issue
and fix it , than You would if they just came and fixed it .

Fred H.

 

[James Eric]

A Good Electrician Would be able to Diagnose the issue likely within a few minutes by simply using several different meters / tools . If you tell them
/ describe the problem as you did above , they would be able to narrow their focus to only a certain area , i.e. that specific circuit , etc.. .

Are We talking 110/120 welder or 220/240 welder ? If 110/120 , Are ALL outlets fed by the same Breaker ? If Not , Switch outlets . Would Eliminate wire from box to outlet . If they are all off the same breaker , try going to a outlet on opposite side of shop .

Some thing to Also consider is Your Ground . Insufficient Ground will play Heck stuff , especially high power stuff .

Honestly Though , If you are not sure about electrical work and will have to hire some one , You won't pay them hardly anymore to diagnose the issue
and fix it , than You would if they just came and fixed it .

Fred H.

It is 220/240.

 

[James Eric]

Here is the additional information with pictures. In live in Maryland southeast on Washington, DC in Prince Georges County. The 4 gauge cable to the barn came with the house. I had the new boxes and the ground at the barn installed.

This is the panel that feeds the barn. The cables are 4 gauge copper with a bare wire which is being fed from the house main breaker panel.


This is the disconnect in the barn. It is tied to 2 ground rods that are spaced 8 feet apart and attached to the disconnect with 6 gauge copper cable.


And finally, this is the breaker panel inside the barn that feeds all of the barn services.


I hope these pictures and details help to explain the cause of the problem.

Thanks,

James

 

[CNC Dan]

Use a multi meter to measure voltage at the plug, when welding. If it drops a lot, you have a bad connection somewhere.

 

[Fawken]

It's hard to tell from the pictures, but in the picture of the disconnect box it looks like some of the #4 Cu strands have been trimmed to fit in the lug. However, the two main facts we are missing when troubleshooting barn power are: (1) How far from the house service entrance to the welder in total wire footage? (2) What is the #12 romex powering in picture #1? Must be something at the house obviously, but what? Air conditioner? Refrigerator?

All of the pictures show very sloppy work that would fail inspection here, BTW.

 

[FredH]

Assuming the 2 wires on the left in the disconnect box are the power from source to disconnect box ? ( Same color wire as in the first picture ) . Wire on far left does looked trimmed of some copper to make it fit in lug . Wire next to it is ????? Electrical grease on it ?? I can see the end of the insulation but cannot see any copper ?

Distance , as mentioned , can also be a issue . Although I don't think you are pulling more than 40 amps , that breaker would trip . Thinking that You are not getting 40 amps to barn . Seems like a lot of panels to go through , but then again I have My Main breaker on utility pole , a panel on back of house that feeds the heat pump , the main panel in house and a panel in shop , ( more or less like a big junction box / splitter box ) . Shop gets fed by a 60 amp breaker in that panle on back of house , which will run my air compressor and plasma at the same time without issue .

If it was me , I would make or buy a cord which your welder would plug in on the one end and on the other end would be just the wires , ( similar to the power cords you can buy for Dryers , etc.. ) . I would start at that panel in first picture , turn off breaker , pull those wires out and put wires from the cord to your welder in breaker and try it . If it works there , then you move to the next box and repeat process . Just remembering to Turn Off breaker Before any wiring is done . If you turn off breaker that feeds power to the panel you are working at , then No electrical to box = No risk of shock .

I am not a certified electrician but I have done work on My place and at My Dads that has passed inspection But it just depends on what you are comfortable with .

Fred H.

 

[James Eric]

Thanks, I will work on it in the morning.

 

[FredH]

Basically What I mean is something Like this Plug or similar that your welder would plug into :



Home Depot , Lowes , etc.......

Appropriate size cord , similar to what is on your welder . One end of is left bare with wires out while other is fed into recepticle and wired up . If welder is 3 prong , then get 3 prong box . Just remember Which wires you use on the 2 side blades and the wire for the ground . Thus the 2 wires you have in box on the side blades go into the breaker and the single wire at top is for ground .
Say Black on one side , White on other side and the Green at the top . Colors may vary , Just keep them the same in box and on breaker .

At the least , it should isolate what section of your grid is the problem . May not diagnose the issue , but may narrow it down to were .

Fred H.

 

[vwnotrunning]

Maybe just try your welder at your friends house! That should rule out electrical issues.

 

[Big Barn]

Maybe just try your welder at your friends house! That should rule out electrical issues.

I like that idea.

Terry

 

[CNC Dan]

Maybe just try your welder at your friends house! That should rule out electrical issues.

Look at the OP's first post.

He kind of did that by bringing his frends welder to his place, and it experienced the same problem. And the problem went away when his friend brought the welder back to his own place.

 

[James Eric]

It's hard to tell from the pictures, but in the picture of the disconnect box it looks like some of the #4 Cu strands have been trimmed to fit in the lug. However, the two main facts we are missing when troubleshooting barn power are: (1) How far from the house service entrance to the welder in total wire footage? (2) What is the #12 romex powering in picture #1? Must be something at the house obviously, but what? Air conditioner? Refrigerator?

All of the pictures show very sloppy work that would fail inspection here, BTW.

The distance from the box to the barn is 160 feet. The #12 is only used to power a powerline adapter so that I can internet service in the barn. The voltage drops from 121 to 112 (sometimes 108) when I start my compressor. I tested both legs. It returns to 121 in a fraction of a second. That was the only way I could test it without help. I am assuming that the welders DC motor would draw as much as the compressor at startup.

 

[Fawken]

As suggested, have you tried operating the welder at the house? Another thing is to safely isolate the buried feeder wiring and use an ohmmeter on the Rx1000 scale to see if there is leakage to ground. All of my shop and barn wiring is outdoor rated and in conduit but even so I perform this test about once every couple of years. Conduit no matter how well it is sealed will be full of water in a year or so and you have no idea if there is a splice or nick in the underground wiring. If so the ohmmeter will show it. As I said turn the breakers off at both ends of the line and read the hot legs relative to ground.

 

[Illini22]

Where does it drop voltage? At the outlet, then test at the barns panel when starting the compressor. If it drops at the panel, keep working up stream. If the other legs voltage raises then you have a neutral problem.

 

[Jimbrown]

Well I had that problem. Going one size up on the gun nipple fixed it. I think I went fro .035 to .040. even though I was using .035 wire.

 

[pat32rf]

Don't know about Texas but as a retired serviceman of 25 years, I would much rather have a little extra wire in a box than wire that is straight with sharp square corners. When you have to make changes due to updates or bad connections that extra wire is GOLD....
When I look at the panel, I don't see any sign of discolouration from loose connections under load. Might be something at the OTHER end of the wire though...

 

[James Eric]

This week I checked all of the connections and made them tighter. I am now getting 237-238v steady with the welder running at maximum power. It must have been a loose connection somewhere. Thanks for all of the input. It really helped.

James