Linclon 125 DC 115 volt is tripping the breaker

[Bill_C]

I regularly run my Lincoln WeldPak 100 on a 12/3 extension cord without difficulty. (Don't get too worried about the differences between the 100 and 125, they both draw the same current and have the same welding output, it's a marketing ploy to label the newer one a "125" but I digress).

There's two main things to consider when sizing wire: the ampacity, and the voltage drop. A 20 amp circuit according to the NEC requires 12 ga wire, with a few exceptions being allowed (one is welding where the duty cycle can be factored in). 14 gauge likely would be allowable for a 20 amp dedicated welder circuit (I suspect, without doing the math).

The other factor though is voltage drop. Wire is a resistor, according to Ohm's Law it will drop voltage as a function of the current going through it times the resistance (V=IR). For high current loads, and long runs, voltage drop becomes significant. Pull 20 amps through a 100 foot 12 gauge extension cord? The voltage on the outlet end will be quite lower than the -120 volts or thereabouts- on the supply end. The solution is to shorten the extension cord, or get a heavier gauge cord (like a 10 gauge).

To your problem, though, which is how to weld without tripping breakers. I try to find an outlet which only has one thing on it, preferably an appliance outlet--like the dishwasher (I use my dishwasher outlet a lot and run the extension cord out the kitchen window). Or the washing machine outlet. (Of course don't run either of those appliances while you weld if you're plugged into their circuit). You should look in your breaker box to see if there are ANY 20 amp circuit breakers, if so use the receptacle on that circuit and unplug any other loads from that circuit. Even if the other loads are only lights.

Use the shortest, heaviest extension cord you can to get from the receptacle to your work.

Proper welding technique helps too. Keep the correct stickout, around 3/8 or 1/2 inch, not shorter. If you're constantly getting the tip shorted to the work it'll draw more current and trip the breaker.

I don't recommend sticking a 20 amp breaker where there is presently a 15 amp.

 

[_RaT_]

I regularly run my Lincoln WeldPak 100 on a 12/3 extension cord without difficulty. (Don't get too worried about the differences between the 100 and 125, they both draw the same current and have the same welding output, it's a marketing ploy to label the newer one a "125" but I digress).

There's two main things to consider when sizing wire: the ampacity, and the voltage drop. A 20 amp circuit according to the NEC requires 12 ga wire, with a few exceptions being allowed (one is welding where the duty cycle can be factored in). 14 gauge likely would be allowable for a 20 amp dedicated welder circuit (I suspect, without doing the math).

The other factor though is voltage drop. Wire is a resistor, according to Ohm's Law it will drop voltage as a function of the current going through it times the resistance (V=IR). For high current loads, and long runs, voltage drop becomes significant. Pull 20 amps through a 100 foot 12 gauge extension cord? The voltage on the outlet end will be quite lower than the -120 volts or thereabouts- on the supply end. The solution is to shorten the extension cord, or get a heavier gauge cord (like a 10 gauge).

To your problem, though, which is how to weld without tripping breakers. I try to find an outlet which only has one thing on it, preferably an appliance outlet--like the dishwasher (I use my dishwasher outlet a lot and run the extension cord out the kitchen window). Or the washing machine outlet. (Of course don't run either of those appliances while you weld if you're plugged into their circuit). You should look in your breaker box to see if there are ANY 20 amp circuit breakers, if so use the receptacle on that circuit and unplug any other loads from that circuit. Even if the other loads are only lights.

Use the shortest, heaviest extension cord you can to get from the receptacle to your work.

Proper welding technique helps too. Keep the correct stickout, around 3/8 or 1/2 inch, not shorter. If you're constantly getting the tip shorted to the work it'll draw more current and trip the breaker.

I don't recommend sticking a 20 amp breaker where there is presently a 15 amp.

Well said Bill. I might add that for a circuit using 120V, the hard wire i.e. Romex or NM wire will be 12/2 with ground, not 12/3. Its not that its wrong but rather unnecessary.

PS, Bills right about the duty cycle factoring in concerning wire size and breaker size. In this case it makes no sense really to even figure it out, use #12 wire and a 20 amp breaker. I suspect that #14 on a 20 amp breaker could be used based on a 20% duty cycle the welder has but that would pretty much mean that circuit would be sized for that welder and thats it, smaller yes, larger no. If you used that circuit to run heaters that drew say 18 amps, that #14 wire would get very hot and eventually compromise the surroundings aka fire.

 

[DiskDoctr]

Sounds like you are well on your way!

A note about wire sizes. In general, an undersized wire will still carry electricity above its rating. But at some point it will start to build heat. Heat reduces its ability to carry the amps, which builds more heat, and the cycle continues.

At some point with increased amps on the line, the heat can build enough to melt or burn the insulation off the wire, ends, or somewhere else. If this happens inside the wall, you have real problems.

So in most cases, bigger is better, within reason. (Don't use a 500lb/ft cable for 20 amps )

The advice given by everyone is good. I wanted to help you understand why it's so important. Also, if the extension cord or receptable gets warm...you know why and that you need to keep an eye on it.

Hope this helps.

- JC

 

[Bill_C]

Good catch on the 12/2 with ground, I had not yet woken up.

For those who don't know, 12/3 has 3 conductors all the same 12 gauge; 12/2 with ground has the 2 main conductors at 12 gauge but the ground is a lighter gauge (because in a 120 volt circuit it normally wouldn't be carrying current). So 12/2 with ground is cheaper and typically used.

 

[Inspector507]

For those who don't know, 12/3 has 3 conductors all the same 12 gauge; 12/2 with ground has the 2 main conductors at 12 gauge but the ground is a lighter gauge (because in a 120 volt circuit it normally wouldn't be carrying current).

Sorry, 12/2 with ground has three wires all #12, a black, a white and a ground. 12/3 has 4 wires all #12, a black, a white, a red and a ground.

 

[Soundguy]

it's only stiff because the wire is so thick.

soundguy

rat he mentioned it being stiff so I just wondered , my extension cords don't seem too stiff. The 220, 110 volt combination is what I was getting at, there is some possibilities to use it to make your work more convenient, but I wouldn't describe it because someone might goof around and get hurt. Others might think of it their selves but I don't know if it would meet code however we have used it successfully. Sorry for talking around in circles but I wouldn't want to advise someone how to do something and then they get hurt.

 

[ampa]

I was just talkin' to my eldest son....the one with new house on 13 acers of land....he bought the same Lincoln only his is the 140 still uses 110 volts....I asked how it was working and told me it was tripping the 15 amp breaker....I asked him what did you do take it back and get a 230 volt.... he no dad....I put in a 20 amp breaker....I seen his house after the electrician left...all the wiring was 14/3....with the exception of 230 volts for the kitchen stove and the clothes dryer....and he had the electrician install a 230 outside to run his 230 volt stick welder.....this is the reason he wanted 110 so it be more portable....he says his runs fine and does almost as good as the stick welder.... just more portable and he's welding at least up to 1/4" on his two gravel trailers all the time.....but this guy is good at welding with anything you give him.....I had him weld some rocker panels years ago on one of my old cars....and all I had was a little el cheapo disposable propane and oxygen set....but he brazed a nice small even bead on both panels....he told me at first to go rent a proper set at this do it yourself garage.....he didn't believe himself when he finished....he finished both sides and I still had a little propane an oxygen left...I gave him the set for doin' the work.....and he used them up until he got the set he wanted...so I guess there are welders that are welders....and I'm not one of them....that receptical has maybe at most 12" of 14/3...I'm just gonna' pop in the 20 amp...and like I mentioned keep an eye on things if gets too hot... no two ways about it....I'll have to upgrade to heavier gauge....now if I lived in the UK...I'd have no choice than to get a 240 volt welder....or whatever power they run over there......once again guys.....thanks a whole bunch...and take care....Ampa :thumbsup:

 

[toy]

it's only stiff because the wire is so thick.

soundguy

I think I have a piece of the wire that you are talking about and I opted not to use it for that reason. The next time I am out to the garriage I'll see if I can read the label on the wire and the label on the more flexible wire, I know there is one kind of wire that is more flexible, easy to roll up when you are finished with it.

 

[Bill_C]

Sorry, 12/2 with ground has three wires all #12, a black, a white and a ground. 12/3 has 4 wires all #12, a black, a white, a red and a ground.

Gosh, you're right. It's only when it goes down to 8 gauge that the ground is smaller, (8/2 w/ground or 8/3 with ground).

https://images.tradeservice.com/gjPilrcyNvvpVtln/ATTACHMENTS/DIR100019/SOUWIRE00006_2_1.pdf

 

[ampa]

First nice day I'll be tryin' out welder....I'll keep you guys updated....Thanks take care...Ampa