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Complete noob shop wiring need help

West-7

Aluminum
Joined
May 24, 2019
I'm trying to set up a shop in a double car garage and will be running several machines a big air compressor and welders with a phase converter and possibly converting some of the equipment over to single phase for convenience so I don't have to run the converter constantly.

So far the garage only has 120 and a small panel with 4 15 amp breakers that appears to be running from a 30amp breaker in the main panel in the house which has a 200amp main breaker.

If I already have that small panel in the garage running off the 30a 120/240 breaker does that mean I already have 240 and just need to put in another panel for it in the garage or will I have to run additional wiring in the house to get 240?

Trying to get to the point where I can run at least 1 machine at a time to start making parts and will fully upgrade in the future. I think I may have 3 phase running along the highway by my property but I'm sure it would cost a small fortune to run to the garage.
 
for your safety hire a professional.

If you have two hot wires, generally speaking in domestic service in this country you have 240(ish). If the breaker for the sub-panel takes up two positions or slots in the main panel, you have two hot wires, but the current you can draw is limited by the size wire feeding the sub-panel. 240 30A can run one efficient welder, one medium compressor or one machine at a time. thats all you are going to get without running new wire to your sub-panel, but also consider the age and condition of the wiring. the demands of the type of industrial loads you are intending to place on the old work can cause problems to reveal themselves.

having a pro run a new sub-panel would be highly recommended.
 
for your safety hire a professional.

If you have two hot wires, generally speaking in domestic service in this country you have 240(ish). If the breaker for the sub-panel takes up two positions or slots in the main panel, you have two hot wires, but the current you can draw is limited by the size wire feeding the sub-panel. 240 30A can run one efficient welder, one medium compressor or one machine at a time. thats all you are going to get without running new wire to your sub-panel, but also consider the age and condition of the wiring. the demands of the type of industrial loads you are intending to place on the old work can cause problems to reveal themselves.

having a pro run a new sub-panel would be highly recommended.

Thank you. The breaker for the garage does take up two slots so hopefully I'll have two hot wires. I just need to run a single machine at a time for now.

Hmmmmm..me thinks you might want to seek out "Professional Help"....

I'm a autodidact so I plan on doing some research and figuring it out myself. If I don't post again you'll know why :)
 
FYI, I run my entire shop off of a 5 hp phase convertor fed by a 30 amp 2 pole breaker. The welder, on the other hand, is running off a 60, which it trips often on startup. How big is the welder? If you need cables to hook up machinery, e-mail or message me as I have a number of pieces for sale and maybe a disconnect or two.

Pat
 
Most people would run a service line from their main box to a disconnect switch in the garage.
All it takes is a 40 or 50 amp break in the main box, a run of conduit, a 60 amp disconnect switch, and a small breaker box. The only hard part is the planning. You only want to do this once.

Maybe you can use the existing wire path to run what you need. That might be pulling new wires through existing conduit if there is room. Around here a wiring job like that is supposed to be done with a permit and inspection. But I doubt everybody obtains a permit for such a small job.
 
30 amps will not be enough, especially for welding.

It may be enough for one or two machines plus lighting

I ran a pretty significant shop[6 3 phase machines, ~20hp], on a 60 amp single phase breaker, it started popping, and the electrician based on the wire size we could up it to 70

moved out soon after
 
A little OT. I once got ambitious and decided I was going to change out the old glass fuse box in my garage to a breaker box. What a royal pain in the ass that was! I would never undertake something like it again, and that was just swapping boxes and (more or less) re-connecting stuff. What you want to do should be done by a professional IMO, or at the very least you yourself should have good firsthand knowledge...
 
I ran all of my 220 equipment using a 50 amp breaker for each machine and 6ga wire in 3/4 emt. I have welders, plasma, a 5hp 2 stage Ingersol compressor, a lathe and mill. I feed the main panel with a 200 amp service. You can never have too much power.
 
I'm trying to set up a shop in a double car garage and will be running several machines a big air compressor and welders with a phase converter and possibly converting some of the equipment over to single phase for convenience so I don't have to run the converter constantly.

So far the garage only has 120 and a small panel with 4 15 amp breakers that appears to be running from a 30amp breaker in the main panel in the house which has a 200amp main breaker..

Post a pic of the panel, please.

If I already have that small panel in the garage running off the 30a 120/240 breaker does that mean I already have 240....
Yes.

....and just need to put in another panel for it in the garage or will I have to run additional wiring in the house to get 240?

You may not need another panel, depending on what you already have.

Trying to get to the point where I can run at least 1 machine at a time to start making parts and will fully upgrade in the future.....

Very doable.

Post a pic of the panel in the garage, preferably with the cover off, and we can start there.
 
Looks like that's SER cable feeding it, probably #8 AL. Technically not supposed to be used underground in conduit or not code wise. Generally I'd use #2 Al for a sub panel as it dosen't cost much more then #10 UF and can be protected at 90A, the required 4 conductors fit In 1-1/4 pvc.
 
IMG_1237.jpgIMG_1239.jpgthumbnail_Excello 40 taper.jpgIMAG0754.jpg

First machines and welders going into the shop

12x30 standard modern utilathe
10x20 utilathe
excello 602 mill
miller cp200 and 52 miller feeder
ac/dc 250
little miller 110 mig
big 3 phase miller stick welder

way more to come
 
Looks like that's SER cable feeding it, probably #8 AL. Technically not supposed to be used underground in conduit or not code wise. Generally I'd use #2 Al for a sub panel as it dosen't cost much more then #10 UF and can be protected at 90A, the required 4 conductors fit In 1-1/4 pvc.

I can probably feed thicker gauge cable through the existing conduit the garage is maybe 10 feet away from the house and the wiring runs from the crawlspace straight to the side of the garage.

Just have to do a lot more research since I've just ran machines in the past never had to install or set them up.
 
Looks like that's SER cable feeding it, probably #8 AL. Technically not supposed to be used underground in conduit or not code wise. Generally I'd use #2 Al for a sub panel as it dosen't cost much more then #10 UF and can be protected at 90A, the required 4 conductors fit In 1-1/4 pvc.

generally, I would NEVER use aluminum wire for anything!

well, maybe light duty binding wire...

forget about using the old 3ph stick welder, they work by wasting the current not going to the arc, super inefficient, ridiculously so. sorry to be a bit harsh here, but except for the new unit, I'm inclined to see the other three as scrap, CP200 is just a constant voltage variant of the "buzz-box" with the crank on top, (not to knock that, it was my first welder!) but not really a good MIG power supply. the dial-arc, another highly inefficient unit. with your limited power, these are poor choices.
 
Yeah, you're gonna need more juice. I'd probably run #4 or #6 copper and a larger breaker box. That should give you enough to cover a decent phase converter as well.
 
First, with 99.99% certainty, you have 230 Volts in that panel. If it is fed by a 30 Amp breaker, then the wiring to it may only be capable of 30 Amps or just a bit more. If you look at the wire you can probably see the gauge printed on it. And that will tell you the story. It does appear that you have four open spaces in that box so four additional circuits would be fairly easy. Or 1 230V and two 115Vs. Another thing you should be aware of is that they do make double breakers so a single position could hold two circuits and two adjacent positions could hold two 230V circuits (yes you have to use two positions for 230V).

The gauge of the cable that feeds that box will be the thing that determines just how far you can go without pulling new wire to it.



 
View attachment 258464

Hard to tell whether this box will accept a 220 breaker. The sticker saying "do not remove these twistouts" is an indication the box hasn't room for more breakers, but it's not for certain that 220 couldn't be installed in place of what's already there.

A pic of the guts of the box, with the cover removed, should clarify things.
 








 
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