So I've started using a MIG welder and plasma cutter to work with metal in my shop, and it looks like a hobby I'll get into more and more as I become experienced with the use of these and other metal-working tools. Unfortunately, the wiring in my 20-year-old shop doesn't seem to be up to snuff. Here's how the basic wiring is set up: there's a main breaker box in the garage (to whence the main power line from the street goes) some 75 feet away, which is a 200-amp box with several 240V breakers (washer and dryer) and a number of 120V breakers. There's a second breaker box in the house proper, which is a 150-amp unit with a number of 240V breakers (furnace, fridge, AC, etc.) and some 120V breakers. I'm guessing this second box has no bearing on my issue, which is the third breaker box in the shop - this box has no labels at all, but it has three 120V 20 amp breakers. That's it in this box. As best as I can tell, the third box receives its power from the first breaker box, but I'm not sure, as all the power lines are buried. To make things more complicated, there's a fourth breaker box on a post in the yard, halfway between the garage and the shop. I don't know if this fourth box is in line between the garage and shop breaker boxes, or if it's on a separate line. This box is rated for 200 amps and has several each of 120V and 240V breakers, and this box provides power to the well pumps and well house lights, plus a pole light which has since been removed.
I've been able to run the MIG welder, shop vac, 42" shop fan, air compressor, and other power tools using the shop's electrical supply, with no issues at all. However, the 120/240V plasma cutter that I acquired recently seems to tax the wiring in the shop; if I run the cutter for more than 10-15 seconds on a medium setting (~20-25 amps), the breaker trips and cuts power to the cutter. This is not a good thing, as the cutter needs to have compressed air running through the torch for 10 seconds post-cutting to cool down the tip, so a sudden loss of power mid-cut will shorten the life of the torch consumables by a good deal. By the way, the cutter is set up to automatically detect the incoming current and switch between 120 and 240V as needed. How do I best address the issue of the breaker tripping? Obviously replacing the 20A breaker with a breaker with a higher amperage rating would take care of the issue, but I'm concerned about overloading the wiring. Don't want to cause a fire inside the insulated sheet metal walls of the shop.
Finally, I'd like to run 240V power to the shop for future upgrades of my power tools. Maybe not right now, but if upgrading the amperage rating of the shop's 120V power supply requires the services of an electrician, I'm guessing that having the 240V supply installed at the same time as the 120V upgrade would be cheaper than having two separate service visits made.
Before I get an electrician out to my place, I was wondering if you folks could offer any advice - namely, is there a solution I can do on my own, or is this one of these cases where you "don't try this at home"? Also, what can I expect in the way of costs if I have to have the work done by a professional? A ballpark figure would be handy to ward off the sticker shock of the estimates I'd get. Thanks!
I've been able to run the MIG welder, shop vac, 42" shop fan, air compressor, and other power tools using the shop's electrical supply, with no issues at all. However, the 120/240V plasma cutter that I acquired recently seems to tax the wiring in the shop; if I run the cutter for more than 10-15 seconds on a medium setting (~20-25 amps), the breaker trips and cuts power to the cutter. This is not a good thing, as the cutter needs to have compressed air running through the torch for 10 seconds post-cutting to cool down the tip, so a sudden loss of power mid-cut will shorten the life of the torch consumables by a good deal. By the way, the cutter is set up to automatically detect the incoming current and switch between 120 and 240V as needed. How do I best address the issue of the breaker tripping? Obviously replacing the 20A breaker with a breaker with a higher amperage rating would take care of the issue, but I'm concerned about overloading the wiring. Don't want to cause a fire inside the insulated sheet metal walls of the shop.
Finally, I'd like to run 240V power to the shop for future upgrades of my power tools. Maybe not right now, but if upgrading the amperage rating of the shop's 120V power supply requires the services of an electrician, I'm guessing that having the 240V supply installed at the same time as the 120V upgrade would be cheaper than having two separate service visits made.
Before I get an electrician out to my place, I was wondering if you folks could offer any advice - namely, is there a solution I can do on my own, or is this one of these cases where you "don't try this at home"? Also, what can I expect in the way of costs if I have to have the work done by a professional? A ballpark figure would be handy to ward off the sticker shock of the estimates I'd get. Thanks!
And finally, I posted my questions to see if the responses would run along the lines of "Oh, it's an easy fix, here's what you do..." or if they would be more like "Yep, you need an electrician." Looks like the latter wins out. Thanks again, folks!
