Need Help: 240v in Garage?

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64 SRT8 Dart

64 SRT8 Dart

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Good afternoon everyone!

I'm looking to buy a new air compressor and am wanting to make sure I can support a decent one as well as be able to run a decent welder with 220/240.

My dilemma is I know basic wiring but not sure anything above a standard wall receptacle or light switch, lol.
I'd like to put a 220/240 plug or two in the garage but I'm not sure if it would support it. The bottom of the breaker box says 120/240v but I'm not savvy on capacity stuff.

Here's a couple of pics of the inside and outside. Will I be able to wire in this outlet?
Much help is appreciated!!

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Yes, you have 230/240 volts to that panel. It looks like it should be able to handle 40 amps. But it is a subpanel running off a breaker in your main panel so it also depends how big that breaker is.
 
The main in the house is a Siemens I-T-E Indoor Load Center.
Catalog no. G1224MB1100
100amp max w/100amp main
120/240v AC Single Phase 3 wire.
Breaker for garage has the double 50 amp switch.

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12/2 wire I think is what i used for my compressor. A 5 hp 220v is going to need a 30a circuit. My IR compressor recommended to wire in a junction box box without a plug. It's pretty straight forward and plenty of wiring diagrams on the net to do a simple circuit like that. Welders tend to do better on a separate circuit also.

*edit, it is 10g
 
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So, I could actually junction off the garage and have a box for the compressor as I'm also looking at the IR 5hp 60gal. Then I could run a second 30amp to an actual plug for a welder. I just couldn't run them both at the same time. At least I wouldn't have the inconvenience of having to unplug one to run the other.
A video I watched the guy said to use a 10/3 wire as well.
Also, would I need to use a double 30a breaker or would a single 30a be fine? I think the double should be used with a 10/3 wire correct?
 
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64 SRT8 Dart said:
So, I could actually junction off the garage and have a box for the compressor as I'm also looking at the IR 5hp 60gal. Then I could run a second 30amp to an actual plug for a welder. I just couldn't run them both at the same time. At least I wouldn't have the inconvenience of having to unplug one to run the other.
A video I watched the guy said to use a 10/3 wire as well.
Also, would I need to use a double 30a breaker or would a single 30a be fine? I think the double should be used with a 10/3 wire correct?
Click to expand...
14 gauge is 15 amp
12 gauge is 20 amp
10 gauge is 30 amp
8 gauge is 40 amp
6 gauge is 50 amp
 
The double breaker is because 220 has 2 hot wires, so you have a breaker for each
 
So the main panel for the entire house is only 100 amp, and you'll pull 50+ to the garage.
I suppose that would work if you have gas heat, dryer, range. Or maybe the 100 amp panel you've shown is a interior subpanel and you have a 200 amp main panel outdoors holding those high amp breakers including one feeding this interior sub panel. Beats me, but I can tell you how I did mine...
The high amp breakers for electric heat, a/c, range, dryer, interior subpanel are in the outdoor/exterior panel. Basement lighting, etc.. is from my interior subpanel just like yours.
Two additional 220 feeds to my basement were pulled from the exterior main panel. My interior subpanel might have handled the addition of one 30 amp 220 line but I wasn't willing to try.
See pic, the gray rectangle box in that tail pipe is where the 2 added lines enter the crawl space portion and go on to the basement portion. The RV box was added last summer

RV box.JPG
 
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RedFish said:
So the main panel for the entire house is only 100 amp, and you'll pull 50+ to the garage.
I suppose that would work if you have gas heat, dryer, range. Or maybe the 100 amp panel you've shown is a interior subpanel and you have a 200 amp main panel outdoors holding those high amp breakers including one feeding this interior sub panel. Beats me, but I can tell you how I did mine...
The high amp breakers for electric heat, a/c, range, dryer, interior subpanel are in the outdoor/exterior panel. Basement lighting, etc.. is from my interior subpanel just like yours.
Two additional 220 feeds to my basement were pulled from the exterior main panel. My interior subpanel might have handled the addition of one 30 amp 220 line but I wasn't willing to try.
See pic, the gray rectangle box in that tail pipe is where the 2 added lines enter the crawl space portion and go on to the basement portion. The RV box was added last summer

View attachment 1715018061
Click to expand...

The one pictured with the 100amp service is the main for the house. The 50amp is in the garage which was put in by an electrician company here in town with all new wiring throughout the garage, receptacles, etc. I'm sure the service coming to the house is 200amp at the meter but for whatever reason when the house was built in 1962 they used the 100amp service box. The box was replaced at some point and I'm sure they just went with the same amp service previously used.
 
64 SRT8 Dart said:
My dilemma is I know basic wiring but not sure anything above a standard wall receptacle or light switch, lol.
I'd like to put a 220/240 plug or two in the garage but I'm not sure if it would support it. The bottom of the breaker box says 120/240v but I'm not savvy on capacity stuff.
Click to expand...

Be safe and call an electrician.
At least have a professional come out and look at what you have.
Safety first...learn not to burn...your house down:)
 
The lights on, a radio going, a fan or something, and the compressor kicks on your real close if not over 50 amps. You can also do damage to the equipment running it like that. Looks like it would be pulling 50 from 100 leaving the house with 50?
 
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What size are the wires feeding the garage panel? They look too small to support a 50 amp load. If they are #6 or larger (smaller number), then OK. The most important thing in any wiring job is to not overload the ampacity of the wiring.

Also, as the garage panel is a secondary panel, the ground wires must be isolated from the neutral wires. Your box is already setup correctly for this, but don't put any white wires on the green/bare wire buss or vice versa. You can do this on the main panel though.
 
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