IMig 140 Power Supply

[ChuckD]

Hello All,
I purchased a iMig 140 to use for simple jobs around the house. I decided to have a dedicated circuit for the welder. The breaker in the box is a 30 amp. When I plug the welder to a regular 15 amp circuit and set it up for an 1/8 plate using 0.30 wire and a 25/75 mix I can get it dialed in, but the weld is a little cold. If i keep the same settings and plug it into the dedicated 30 amp circuit it burns to hot and almost burns through. The question I have is shouldn't the welder draw only what is necessary for the settings? My gut feeling is maybe the dedicated circuit being only 6 feet from the breaker box has a increased voltage. Any advise would be appreciated.

Thanks,
Chuck
Boise, Idaho

[everlastsupport]

Hello All,
I purchased a iMig 140 to use for simple jobs around the house. I decided to have a dedicated circuit for the welder. The breaker in the box is a 30 amp. When I plug the welder to a regular 15 amp circuit and set it up for an 1/8 plate using 0.30 wire and a 25/75 mix I can get it dialed in, but the weld is a little cold. If i keep the same settings and plug it into the dedicated 30 amp circuit it burns to hot and almost burns through. The question I have is shouldn't the welder draw only what is necessary for the settings? My gut feeling is maybe the dedicated circuit being only 6 feet from the breaker box has a increased voltage. Any advise would be appreciated.

Thanks,
Chuck
Boise, Idaho

Chuck, the unit will only pull what it needs from the panel settings. So how close to the breakers will not cause a problem. If you vary the volts, do you see a change in the power?

[ChuckD]

Mike,
I do see a change in power when I vary the volts. Plugged into a 15 amp circuit the tuning was sluggish, but plugged into the 30 amp circuit it is quite sensitive to slight changes and feels like it has a 1/3 more power. I like having the ability to apply more heat when needed, but wouldn't think that just plugging the unit into a different circuit would make that much of a change.

Chuck

[Elantramax1]

Maybe the 15 Amp circuit is heating up. The Wiring should be a lighter gauge than you would find on a 30A circuit.

[performance]

Well, the wire you are using would limit total input voltage, and under load things may show up in the circuit too that may not be present with a static measurement. Theoretically, there is no way it would make a difference on output unless some other variable is changed like input voltage.

[ChuckD]

Just to follow up I tested the voltage coming through the circuits. The 15 amp circuit travels about 40 ft from the service box to the plug by the time it travels to the back of my garage. The 30 amp circuit travels about 6 ft from the service box to the plug. When measured at the plug the difference between the two is about 9 volts. My contractor accounts this to voltage drop and it is common with how many of the homes are wired around here. We had the same problem with the outdoor outlets at the back of my home which is the furthest distance away from my service box. The service at that location was so weak that certain items would not work if plugged in, but common items like a radio would. According to code it's fine, but this might be what is causing my problem. Using the 30 amp circuit the iMig is performing above my expectations.

Chuck

[Rambozo]

Just to follow up I tested the voltage coming through the circuits. The 15 amp circuit travels about 40 ft from the service box to the plug by the time it travels to the back of my garage. The 30 amp circuit travels about 6 ft from the service box to the plug. When measured at the plug the difference between the two is about 9 volts. My contractor accounts this to voltage drop and it is common with how many of the homes are wired around here. We had the same problem with the outdoor outlets at the back of my home which is the furthest distance away from my service box. The service at that location was so weak that certain items would not work if plugged in, but common items like a radio would. According to code it's fine, but this might be what is causing my problem. Using the 30 amp circuit the iMig is performing above my expectations.

Chuck

To get an accurate reading, you need to measure the voltage when the circuit is under load. I would bet you will see a lot more than a 9 volt drop when welding. Also, a 9 volt drop over 40 feet is not good, either. I would suspect that there are some poor connections along that circuit. Even with a full 15 amp load the voltage drop over 40 feet should be only 3 volts. Running a heavy load like a welder will bring out problems in wiring that might go unnoticed with light loads.

[Elantramax1]

it is Possible that there is something else on that 15A circuit. Door Bell for example. Which would show as a voltage Drop due to the draw.

[Rambozo]

it is Possible that there is something else on that 15A circuit. Door Bell for example. Which would show as a voltage Drop due to the draw.

That won't be enough current to even show much. Even with a full 15 amp load, the voltage drop for 14awg wire over 40 feet is only 3 volts. That you are getting a nine volt drop with a light load, indicates that there are some problems with that circuit. If there are several outlets on that circuit you can start at the panel and go from outlet to outlet to figure out where the issue is. My money is on a flaky back wired push terminal on an outlet. They often become a current limit due to oxidized contacts and poor quality.
But still it's always best to have a dedicated circuit for a welder, especially a 120V model, as they need all the help they can get. Your 30A circuit is a great choice for a welder.

[everlastsupport]

I've never been a fan of welding on 110VAC/15amps. But if you want to use that, I agree with Rambozo 100%. Dedicated circuit and I would pull and clean and reconnect the wire at the outlet. Do all the load testing at the outlet as well in case the issue is in the panel.

[ChuckD]

All,
Thanks for the help on this topic. My breaker box did not have enough room for another 220 so that's why my contractor piggy backed another slot with a 30 amp 115. I wanted a dedicated connection. I agree I would rather be welding with 220, but since I will only be going up to about 1/8 mild steel for most of my projects the 115 should work fine. The company that wired most of the house in my neighborhood is no longer in business. The work they performed was marginal and never should have passed, but sometimes you have to take what you get and make it work.

Chuck

[Rambozo]

Sounds like you have it under control. However, don't rule out getting a 240 circuit installed, if you want to upgrade down the road. Depending on the brand, there are half space breaker combos that will let you pull out two single pole breakers and replace them with a combo of one two pole and two single pole breakers. These are great for full panels and I have put in quite a few of them.
Here is an example of what they look like.