Have one old school 240 outlet in garage - adding extras?

[james92se]

I currently have one 240 volt outlet with breaker panel in attached garage that serves as my "shop". My father installed this at least 30+ years ago. My father has been deceased for 13 years now but my twin brother and I have been using this outlet continuously for all of our automotive projects. As you can see from the attached picture it's the old breaker style (sorry for the quality but I'm using a cheapo temporary phone until I get the new iPhone next week).

My brother and I use this single outlet to run our Hobart Handler 180, Harbor Freight automotive lift, and Ingersoll Rand SS3L3 compressor. Obviously this requires a lot of plugging in and unplugging. I have now acquired an Eastwood Versa Cut 60 plasma cutter and would like to be able to use multiple tools without having to unplug/plug everything separately. Now, it would be very very rare to ever use two tools simultaneously (for example, I wouldn't be actively welding AND raising the lift simultaneously or anything like that), but you get the idea.

The main house breaker panel is in the backyard (back-wall of the house), and was completely re-done by an electrician about 6-7 years ago. The breaker box in the garage is, I guess, a sub-panel because I see the main breaker in the backyard has a 100 amp breaker labeled for the garage.

Now my desire is to have multiple 240v outlets in the garage so I can have multiple tools plugged in at once and able to, in very rare situations, simultaneously use two tools at once if need be.

What would be the textbook way to go about this? I have a buddy who is not an electrician but wired up his own custom built garage and is fairly competent with stuff and he had me purchase several appropriate sized square D breakers (20 amp for the lift, 50 amp for the welder, etc) and a new breaker box for the garage as well as several 240 v 50 amp outlets. I also purchased a bunch of wiring (I can't remember the size, but it's pretty fat stuff). So the plan was to replace the current old-school breaker box in garage with new one and separate appropriate sized breakers for each new outlet. My plan is to have three or four 240v outlets all right in the same area.

The problem is this garage is me and my brother's "shop" but the house and garage are my mother's residence. As soon as she got wind of this plan she is wanting to call an electrician out. My fear is the electrician is going to want an exorbitant price and that with some guidance I could easily do it myself. My brother and I are fairly serious hobbyist automotive fabricators/mechanics dudes but haven't messed with heavy duty 240v stuff before because we've just been using what our dad installed all those years ago.

I also absolutely want it done right and do not want to burn down my mother's house but don't want to pay an electrician if I don't need to.

Thoughts?

 

[justsam]

I hold little doubt but what you could do it right, however it may be more of a piece of mind issue for your mom, and I have to think that has some value.

I can not tell if the garage panel is fed with three or four conductors. By doing the extent of work you are proposing, you would need to bring it up to current code. That would mean 4 conductors to the garage, 2 hots, a neutral, and a ground. That may or may not be too easy if there is conduit in place.

Will you be using conduit to run to your new 240 volt outlets? Wiring must be protected by conduit, drywall, etc.

It would seem a little weird to have all the outlets in one location, but doing as you suggest with each on it's own breaker is the way to do it. As has been discussed here recently you may not have multiple 240V outlets on one circuit.

With plasma, I suspect you may be running both your compressor and plasma at the same time. Your proposed separate circuits will handle this.

 

[james92se]

I hold little doubt but what you could do it right, however it may be more of a piece of mind issue for your mom, and I have to think that has some value.

I can not tell if the garage panel is fed with three or four conductors. By doing the extent of work you are proposing, you would need to bring it up to current code. That would mean 4 conductors to the garage, 2 hots, a neutral, and a ground. That may or may not be too easy if there is conduit in place.

Will you be using conduit to run to your new 240 volt outlets? Wiring must be protected by conduit, drywall, etc.

It would seem a little weird to have all the outlets in one location, but doing as you suggest with each on it's own breaker is the way to do it. As has been discussed here recently you may not have multiple 240V outlets on one circuit.

With plasma, I suspect you may be running both your compressor and plasma at the same time. Your proposed separate circuits will handle this.

The garage panel box is fed by three wires, 2 black and a white. The black wiring says "type thw - phelps dodge - s - habidure - 2 - 600 V - (UL)" on them. The white wire says "general cable m 2 type thw 600v" on it. Is this no longer copacetic? Like I said, I believe this must be at least 30 years old. I'm 31 and this 240 v outlet has existed as far back as I can remember. And yes I assume I would run the wiring through conduit through the attic.

Yes, me buying the plasma cutter and realizing I need to be able to run the plasma and the compressor simultaneously is what started this desire for extra outlets.

So - if I'm understanding correctly, the textbook way to do this if I want three new outlets - I will need "punch out" spaces in the main backyard/outside breaker box for three new separate breakers. Then run the wiring through conduit through the attic then down to my new breaker box (sub-panel I guess it's called?) with each run having the appropriate square D breaker at this panel, and then to each outlet?

As an applicable example for me - my HF lift states it needs a dedicated 20 amp circuit. In this scenario, would I add a 20 amp breaker to the backyard breaker panel. From there run wiring (appropriately sized) from that 20 amp breaker through conduit in the attic into my new breaker panel in garage also with a 20 amp breaker. From there run to my new outlet. And do the same with appropriate sized breaker/wiring for the compressor, plasma, etc.

If the above is correct - and now here is a dummy question - what is the purpose of having a 20 amp breaker at the outside main breaker box and also inside the garage sub-panel?

Also - would each "run" in the attic need to be in separate conduit pipes? Meaning if I had three new outlets ran that I would need three separate lengths of conduit?

 

[wyliesdiesels]

Is that pic the box that youre calling a subpanel? If so then thats NOT a subpanel. Its a fusible disconnect.

The wire doesnt appear to be very large certainly not big enough for 100a. Do u see a gauge label on the wire? Is this wire run through conduit? if so you will at least need to add a ground wire!

Since it sounds like your garage is attached you have 2 options, either run individual branch circuits from your main panel or run a feeder and set a subpanel in the garage.

What is the HP rating of the compressor?

 

[justsam]

The garage panel box is fed by three wires, 2 black and a white. The black wiring says "type thw - phelps dodge - s - habidure - 2 - 600 V - (UL)" on them. The white wire says "general cable m 2 type thw 600v" on it. Is this no longer copacetic? Like I said, I believe this must be at least 30 years old. I'm 31 and this 240 v outlet has existed as far back as I can remember. And yes I assume I would run the wiring through conduit through the attic.

You really need to determine what size (gauge) wire it is now fed with. Is it feed by metal conduit? In the past, three conductors in metal conduit was fine, but now you need to run a forth wire for ground. The breaker in the existing outside box must be sized to protect the wire going to the garage. Once you know the gauge, than you can determine the proper breaker size if the existing 100 Amp is not correct.

So - if I'm understanding correctly, the textbook way to do this if I want three new outlets - I will need "punch out" spaces in the main backyard/outside breaker box for three new separate breakers. Then run the wiring through conduit through the attic then down to my new breaker box (sub-panel I guess it's called?) with each run having the appropriate square D breaker at this panel, and then to each outlet?

NO! The new breaker box in the garage will feed your local circuits in the garage. Since you have an attached garage you could feed each garage circuit individually from the house panel, but it looks like in the past a pseudo subpanel was created via the fuse disconnect.

 

[james92se]

Is that pic the box that youre calling a subpanel? If so then thats NOT a subpanel. Its a fusible disconnect.

The wire doesnt appear to be very large certainly not big enough for 100a. Do u see a gauge label on the wire? Is this wire run through conduit? if so you will at least need to add a ground wire!

Since it sounds like your garage is attached you have 2 options, either run individual branch circuits from your main panel or run a feeder and set a subpanel in the garage.

What is the HP rating of the compressor?

Yes the pic I attached is what I tentatively referred to as subpanel because I knew no other proper term for it. Thanks for clarifying.

What I stated above is the entirety of the labeling on the wiring. I would say each of the three wires feeding the fusible disconnect have a diameter of about 1/2". I'm talking about the actual copper strand section of each wire.

I went into the attic last night to see how the wiring was run from the fusible disconnect to the backyard breaker panel. The fusible disconnect has a galvanized pipe run from the disconnect up to the ceiling/attic. The wiring in the attic, however, is not in conduit. It is draped up out of harms way but the three wires - two blacks and a white, are visible and exposed all the way over to the back of the house where it drops into the backyard main breaker box, again through galvanized pipe. I suppose this is not copacetic and it must be contained in conduit in the attic?

The compressor is 3 HP

 

[james92se]

You really need to determine what size (gauge) wire it is now fed with. Is it feed by metal conduit? In the past, three conductors in metal conduit was fine, but now you need to run a forth wire for ground. The breaker in the existing outside box must be sized to protect the wire going to the garage. Once you know the gauge, than you can determine the proper breaker size if the existing 100 Amp is not correct.

I will try to get an exact gauge on the wiring tonight. Like I said in my post above each wire is at least 1/2" on the actual copper part IIRC.

NO! The new breaker box in the garage will feed your local circuits in the garage. Since you have an attached garage you could feed each garage circuit individually from the house panel, but it looks like in the past a pseudo subpanel was created via the fuse disconnect.

Okay I misunderstood then. So then ultimately there will be one "line" in the attic (when I say one "line" I really mean the four wires) connecting the outside breaker panel to the new breaker box in the garage. And then the new breaker box in the garage will feed each new outlet.

I was thinking that I could not have only a single "run" from the main outside breaker and that I would need a separate "run" from the main outside breaker to each individual new outlet.

Like I said, I'll get a definite on the wire gauge tonight. I definitely appreciate y'alls help.

 

[james92se]

I forgot to post two pictures of the wiring I took last night in the attic. Looking at these pictures now I think my 1/2" estimate is off and I may be remembering them thicker than they were. The sheathing on these wires is not very thick though and the actual stranded copper diameter is at least 1/4" but probably not quite 1/2".

 

[alfredeneuman]

TThe black wiring says "type thw - phelps dodge - s - habidure - 2 - 600 V - (UL)" on them. The white wire says "general cable m 2 type thw 600v" on it.

It appears that is #2 from the writing on the conductors

EDIT : It isn't even in conduit??

 

[james92se]

It appears that is #2 from the writing on the conductors

EDIT : It isn't even in conduit??

No, as stated above I went into the attic last night and it's not in conduit. It is strung up out of harms way, so to speak, but not in conduit. I can add that though - like I said, I want to do this properly.

Is #2 proper for acting as the "feeder" to my new breaker box in the garage?

 

[justsam]

Cable such as romex does not need to be protected in the attic, however you can not run individual conductors in the attic.

I should have asked initially, if your need is ONLY for 240V and do not need 120V or it is already there via some other circuit since this is an attached garage. If all you wanted was 240V than what you have would have been fine, were it not for the individual conductors in the attic. You would not have needed to run a fourth wire for ground but use the white wire, which normally is neutral, and tape it with green tape wherever it appears, and would be your ground conductor. That may be how your existing disconnect/fuse box is wired, if LL it provides is 240V.

To do it right, determine what current you actually need, 100Amps is pretty stout for most, and I suspect with what you are describing, 60Amp or so would be fine. Once you determine what you need in terms of current, than use a proper sheathed cable to provide it of the appropriate gauge. Again if ALL you want is 240, you need three conductors, if you want 120 and 240 you need 4 conductors.

How long of run are we talking here, as copper prices may scare you, and how difficult would it be to put yur existing wires in conduit?

 

[rbjenterprises]

Now IS the time to call an electrician. It will be cheaper and less painful for you.

 

[wyliesdiesels]

No, as stated above I went into the attic last night and it's not in conduit. It is strung up out of harms way, so to speak, but not in conduit. I can add that though - like I said, I want to do this properly.

Is #2 proper for acting as the "feeder" to my new breaker box in the garage?

That all depends on the load. For u if it is #2 cu, then its good for 115a and based on what youve said you will be doing, that should be plent. However, there are other factors which effect useable ampacity such as ambient temperature(in the attic) and length/distance which can cause voltage drop.

Now IS the time to call an electrician. It will be cheaper and less painful for you.

Thats helpful!

 

[james92se]

Cable such as romex does not need to be protected in the attic, however you can not run individual conductors in the attic.

I should have asked initially, if your need is ONLY for 240V and do not need 120V or it is already there via some other circuit since this is an attached garage. If all you wanted was 240V than what you have would have been fine, were it not for the individual conductors in the attic. You would not have needed to run a fourth wire for ground but use the white wire, which normally is neutral, and tape it with green tape wherever it appears, and would be your ground conductor. That may be how your existing disconnect/fuse box is wired, if LL it provides is 240V.

To do it right, determine what current you actually need, 100Amps is pretty stout for most, and I suspect with what you are describing, 60Amp or so would be fine. Once you determine what you need in terms of current, than use a proper sheathed cable to provide it of the appropriate gauge. Again if ALL you want is 240, you need three conductors, if you want 120 and 240 you need 4 conductors.

How long of run are we talking here, as copper prices may scare you, and how difficult would it be to put yur existing wires in conduit?

Yes my need is ONLY for 240. These outlets will literally only be powering my compressor, lift, welder, and plasma cutter. It would never even occur to me to try to use these outlets for 120 and I didn't even know that was a "thing" until I was reading about it this afternoon. I'm glad you mentioned about the three vs four wire because this afternoon at work I was reading about how 240 only needs three wires and does not use a neutral, and I was thinking to myself "well that's how its already wired so what's the problem?" and planned to ask about it now that I'm home but you've already mentioned it.

Here are my needs:

1) HF Lift - manual states it needs a dedicated 20 amp circuit. States 12 FLA/5 min duty cycle

2) IR SS3L3 compressor - manual states it's a 16.6 amp motor. Judging from other owners online, most people seem to run this compressor with a 20 amp circuit but I have seen a few people state they run them on 30 amp circuits "just to be safe" sort of thing.

3) Versa Cut 60 Plasma cutter - manual states 50 amp circuit needed.

4) Hobart Handler 180 - manual states 30 amp circuit but I see online many people run them on 50 amp circuits. I think I would just use the same 50 amp circuit and outlet as the plasma cutter. I would not be simultaneously welding and plasma cutting.

SO - as the current run in the attic stands, is the primary issue that it is currently composed of three individual conductors rather than a single sheathed conductor like a three wire romex? If so, does that mean I can either put my existing wires in conduit OR replace it all with an appropriately sized three wire romex? Each wire in the current run is (as best I can measure) about 5/16" in terms of actual copper strand diameter. So I believe it is 2 gauge like the poster above believes. It would not be hard at all to put the current wires in conduit. It is all totally accessible and open in the attic. If I were to make an all new run, I would need about 50 feet, measuring conservatively.

Could I not sheath the current run in conduit, run it to my new breaker box consisting of a 20 amp breaker (lift), a 30 amp breaker (compressor), and a 50 amp breaker (welder and plasma), and the three outlets run from there?

Now IS the time to call an electrician. It will be cheaper and less painful for you.

I'm not sure if you intend that to be patronizing/rude or not, but an electrician has been called and will be here tomorrow at 10:30 AM. Please know I'm not trying to kill myself or burn my mother's house down - hence me asking for advice from you all on here who obviously know better than me. I truly want to understand/learn the proper way to do this. If I'm capable of doing that myself with the advice of knowledgeable people here, I don't see why I shouldn't. I am curious to see what the electrician will say but that does not mean I'm eager to pay him an arm and a leg for something I may be capable of safely doing myself.

 

[wyliesdiesels]

Yes the cable needs to be put in conduit. Individual conductors cant be freely hanging. And if used continuous metal conduit such as EMT with bonding rings on each panel, then the conduit can be used as the ground giving u 4-wire feeder for 120v/240v!

Edit: forgot to add about wiring requirements for welders and compressors.

Wiring for Compressors/motors needs to be sized @ 125% of table FLC(17a for 3hp) equaling approx 21a wire(so #12 thhn or #10 NMb) and breaker can be a max of 250% of FLC.(breaker is for short circuit an ground fault protection only, overload on motor or starter protects motor and wire!

Outlet can be used for motor rated upto 3hp, beyond that needs to be hardwired!

Welder circuits can have undersized wire/oversized breaker based on duty cycle of welder but circuit must be labeled for welder only!

 

[justsam]

If you put your existing wire in a continuous metal conduit run, than you really do not need to buy any more wire for the feed run. I am surprised that was not done initially since much of the hard work was done, why not finish it.

I would use the existing 2 blacks for each hot leg and the white as a neutral. The neutral is really only required for 120V, but since it is there it is the right way to do it. It will just be terminated in the new breaker box, just as the two hot leads are. The bonded conduit is ground.

You will need some 120V near your other gear, either to operate auto drain valves, water coolers if you do TIG, spool gun if MIG, sanders, etc.

It is just the right way to do it, and for the most part is already there, just need to complete conduit.

Others have commented that motors are based on HP as well as current. Must be hardwired if over 3HP. In the interest of full disclosure my 5HP is on a plug and socket that is rated for the current, but technically is not code.

I should add that if your new breaker box winds up with more than 6 breaker handles, (240v are two breakers with one handle since they must be tied), than you will need a main breaker in the box.

 

[james92se]

I will say that I know for certain I won't want (need) any 120v outlets near the new 240v outlets. The rest of the garage is already outfitted with multiple 120v outlets and the garage has been essentially "designed" around the current 240v outlet. That is why, though it may sound odd, I want all of the new outlets all in close proximity with eachother - because the garage is already set-up for that "spot" to be the 240v power "spot" and we have already been working in that manner since we were teenagers. Compressor is already right there, welder stays in that spot (though we do have a beefy extension cord for it), and lift equipment stays in that corner too.

On a side note, I had not heard about the 3hp hardwired compressor bit until now. Prior to my purchasing the IR 3hp unit about 2 years back, we were still using my dad's old behemoth 100 gallon 1960's industrial compressor. We never did know the specs on it but it was massive and loud as all heck. It looked very very very similar to this one, identical color, but was noticeably taller.

My dad bought it used in the early 70's when he opened his auto shop and ultimately it was in continuous operation for over 50 years. Pretty impressive really. Anyway, I am absolutely certain that thing was at least a 4-5hp and was just on a plug and this same socket in question in my thread here that whole time. He was a professional welder and ASE master tech - so I'm not sure if my dad didn't know any better about the hardwired bit or did know better and just didn't care and wanted the convenience. If I had to guess I would say the latter. The same outlet also powered my dad's Hobart Beta-Mig 200, which we still have and operates flawlessly but don't ever use.

Anyway, thanks so much for your input fellas. I very much appreciate it and feel I have a good grasp on the proper way to do this now.

I'll let you all know tomorrow what the electrician says and what we end up doing.

 

[james92se]

Okay, electrician has come and gone. He was very nice and even offered to walk me through it if I wanted to do it myself and in a nutshell basically stated what you guys said above.

I had already purchased wiring, the breaker box, the breakers and the outlets. My mother decided she wanted to have him do the work with the parts I already bought. He'll be doing that this Friday for $150 and I will be putting the wiring in the attic in conduit.

Thanks for all your input guys.

 

[volleyball]

Your mom is wise. You really need to give her a big hug.

 

[themiller]

This forum is great isn't it!

 

[james92se]

Your mom is wise. You really need to give her a big hug.

This sounds like a snide comment along the lines of the guy above

This forum is great isn't it!

Yes it is. I've been lurking and reading for a long time but this thread is my first time posting

 

[volleyball]

It is not a snide remark. You sound young and it is her property and kids. Just because you feel skilled in one area doesn't make you skilled in another.

 

[Bib Overalls]

Electrician comes out twice, once to look and once to work and does the job for $150? That seems very reasonable. Where are you?

 

[james92se]

It is not a snide remark. You sound young and it is her property and kids. Just because you feel skilled in one area doesn't make you skilled in another.

Nobody knows how to do anything until they ask questions and learn. That is exactly why I came here because I am not skilled in this area.

So this forum helps me figure out exactly how to do it - electrician confirms on-site that is exactly how to do it. You feel that means I'm still incapable of physically doing that simply because prior to this I unsure how to do it?

Everybody was once totally ignorant in any field. I know you were young once and are likely an expert in your own right in some field(s) and (gasp) - were probably totally ignorant in the beginning and (double gasp) probably had to ask an expert what must have sounded like stupid questions to them.

To have that attitude about somebody genuinely trying to learn something (stupid questions and all) simply comes off as snide, that's all.

Electrician comes out twice, once to look and once to work and does the job for $150? That seems very reasonable. Where are you?

Southeast Dallas

Older guy (mid-late 60's maybe?) and I believe is semi-retired. He seems like a very nice man. He even offered to come back out and "walk me through it" if I wanted to do it myself.