What size wire would I need to get 150 amps

So, in order to get things up and running, I have to get 220 volts from the service box to the work area. Of freaking course the service entrance is as far away from where I want my outlets as I can possibly get. I need to run about 44 feet. I'm wondering what gauge wire I need to get about 150-200 amps. This should be enough to run my plasma cutter, wire feed, and that shiny new 250 ex that I plan on having sooner, than later. Plus plans call for a Bridgeport mill with a 3hp motor, and a healthy air compressor to run a blast cabinet. Any Ideas how to get this done?

One alternate source of info: selfhelpforums.com is a forum for DIYers but they seem to be very focused on electrical work. Some of their forum subheadings are for information about passing electrical certification exams, for instance. You might cross-post there and get some good info~

Hooda,

It is my understanding that the NEC allows 5% voltage drop, but you MUST verify your own compliance with local codes.
For 200 amps over a 44 foot wire length run, it looks like you could get by with #8 wire, but that would 4.7% drop.. kind of on the edge. The bigger #6 would be 3% voltage lost, and #4 would be 1.9%.

Head over to http://powerstream.com/Wire_Size.htm and you can use the calculator to figure awg/feet/volts and find what is suitable for your application.

Been there done that, have 3 phase power at one end of the shop, then have another 3 phase panel by the man door, run over head on top of the roof rafters, massive cable don't know the guage but I do know the electrician used special tools just to bend the wires during hook up to the sub panel. now I find myself running another welder plug back towards the big doors on the opposite wall towards the main 3 phase panel. What ever you do will be expensive and should be done by a qualified electrician, covers off on your fire insurance.

I'm in the middle of rewiring my shop, which is actually an attached garage. Fortunately, I have two professional electricians with decades of experience to assist (and hook me up with wholesale cost parts). The current rewiring project includes two 20 amp 110 drops for lathe, drill press, grinders, etc. The other main venture is a pair of 50 amp circuits, one to run a kiln and powdercoat oven, one to run a large air compressor and welders. We're running #4, one is a 20' run, the other ~30'

Depending on how the winter works out, I'm hoping to add a nice Bridgeport, though I won't be running 3phase, but rather a converter tied into the first 50amp. The lathe I have now is single phase, but may be replaced if I can figure out how to haul a 16"x6' Southbend across town... not sure if I'll run it 3 phase or swap out the motor.

Remember, the wire can be too small, but it's hard to make it too big... I always err on the side of caution and go up a gauge when planning things myself.

As a follow-on to Geezer's point about fire insurance, does your lease or rental agreement allow you to make this kind of modification to the building?

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Originally Posted by hooda

So, in order to get things up and running, I have to get 220 volts from the service box to the work area. Of freaking course the service entrance is as far away from where I want my outlets as I can possibly get. I need to run about 44 feet. I'm wondering what gauge wire I need to get about 150-200 amps. This should be enough to run my plasma cutter, wire feed, and that shiny new 250 ex that I plan on having sooner, than later. Plus plans call for a Bridgeport mill with a 3hp motor, and a healthy air compressor to run a blast cabinet. Any Ideas how to get this done?

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Assuming you're getting power from your house... If you plan to pull 150-200 amps (use all machines at once) you need to contact your electric service provider and have a new service run to your shop (seperate meter). 150-200 amps is too much to pull from your house. A residential service line is usually 200 amp wire.

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Originally Posted by zoama585

150-200 amps is too much to pull from your house. A residential service line is usually 200 amp wire.

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Depends on the locale and size of the property, here in N. FL, houses under 2000 sqft are run 150amp and even some larger houses. Older houses can even be 100amp. Regardless if it's a residence or not, find an electrician that will take a look and tell you what's what, a friend of a friend (professional, not handyman or joe-homeowner) or call your electric company, they'll usually be happy to answer basic questions about what's run to your house, if you have enough power, etc. Or, call an electrician. May cost you $50 to come out and look things over, but better safe than sorry.

Herein lies the problem. I'm trying to get my little business started with just about NOTHING!! Not by choice, but because that's about what I have. I'm needing to get just enough business through my door without the use of my welder or plasma cutter..to get the money I need to hook up my welder and plasma cutter:mad: I have a few people wanting small engine repair, but overall, this is the most challenging part of getting something like this going. So, as far as running the wires, I have looked into the costs involved, and I have no choice but to make a go at this myself. I basicallly need to know what gauge I'd need in aluminum. I looked into the costs involved in doing copper, and it's literally 4 times the price.

Just get the direct burial mobile home service wire. That will do what you need at a reasonable cost.

Thanks Mark. I spotted that stuff at the local big-box, but just needed someone to say to say it might work!

Like I said, my electrician ran #4 AL wire for a 50amp breaker in about a 30' run... YMMV

Hooda, go to google and type in Wire size calculator, many programs that will answer your questions, a good source of cheap heavy wire is the installers on subdivisions,(min hoe operators) quite often they have shorter roll ends of the underground cables for house services, too short for a service but just right for your needs. It's heavy underground cable but works fine above ground.

I think I would reconsider trying to run a sub box that has 150-200 amp capacity, and instead, run a single circuit that will cover your demand, and use a receptacle / plug for your equipment. Since you are a one man show, you won't need more than one piece of equipment at a time. It will be MUCH cheaper to run a 50-60 amp circuit than a 150-200 amp, both in the conductors, the breakers, switches, etc.

I agree with sportbike, but I'll add that you should size it for your biggest draw PLUS the air compressor. generally speaking, you won't ever be running more than one of the 'main draws' (stick welding, lathe, mill, ect, tig alu, plasma) plus the air compressor. you should be able to get away with a 100a sub panel (although, I'd recommend spending the extra few bucks for a 'main' panel with a full disconnect for the shop, even though it's going to be wired as a sub panel. I put a 200a sub in the shop I work in a few months back and having to walk 200 yards over to the building the feed breaker is on is a real pain if you need to move a breaker in your new panel, ect.).

if it were me, I'd go 2ga copper if it were me, but your funding may not allow that. 44' isn't that far, in the grand scheme of things. my Imig is plugged into 50' of 8-3 extension cable and about 25' of 6-3 back to the panel. no issues.

since you're just trying to get on your feet, if the welder is the biggest issue, buy yourself a 50' run of 8-3 SEOOW extension cable (6-3 would be better, but it's a big jump in price) and some ends and run that for a while. until you start making some money, you can work off a harbor freight POS air compressor that will run off a 20a breaker (I'm assuming here that your garage has at least lights and a couple of outlets). 50' of 8-3 and ends cost me about $140 in may here in waco, to give you an idea.

Thanks, Geezer for the idea I googled "wire size calculator" and got this link.
http://www.paigewire.com/pumpWireCalc.htm
All I had to do was type in 45 ft, 240 volts, 45 feet, And for copper I need 2/0 and for aluminum I need 3/0. If you were to take a look at the prices for copper these days, It only makes sense to run aluminum on a circuit this size, especially in light of the fact that I'm a renter, not an owner. I think what I'll do is follow geezer'sidea and do a stalk-down of a few commercial job-sites around here and try to score the appropriate sized wire fron a sub. Too bad Tony Soprano's crew isn't sittin' around lookin' to make a few ez bucks:D. Either way, I look at the cost to actually get the wire, and the pvc conduit, with connectors and junctions to total under $5.00 a foot, so I think I can pull that off. With this big of a service draw, I think I'll install a separate circuit breaker box in the shop area. The way I look at it, The MTS 400 MIG machine pulls 55 amps in 240/single phase, and the max inrush amps on the powerplasma 80 pulls 70 amps at 220 volts. With 150 amps, I have enough to run my current equipment, and MORE than enough to run what I hope to have as an all-EVERLAST equipped shop in the future. You see, I got into yet another argument about buying BIG red and BIG blue versus "that imported s*$&", and not only won the argument, but convinced the guy that, If I get in a 50 or 60 amp plasma cutter, and it'll do what I promised him it will do, he'll buy it, no questions asked. I'm now giving serious thought to the idea of becoming a dealer here in the Minneapolis area. But that's in the future. For now I'm sticking with repair, fab, and welding.

hooda, my book says that that is way too big. My book states that #2 Aluminum should handle 150 A at 240 VAC over 45' with only a 1.76% voltage drop. My electrical cooperative confirms this would be correct.

Thurmond