Need Help With 230V Circuit Addition

[Vista]

I'm thinking about getting a 230V welder (Hobart 190/Millermatic 180 class) and would like to put a dedicated 230V circuit with two plugs in my garage. One plug would be near my workbench (about 10 feet from the electrical supply panel on the outside corner of the garage); the other plug would be at the front corner of the garage near the overhead door opening about 30 feet from the same panel.

I've attached pictures of the outside electrical service panel The first shows the breaker panel setup, the second is a closer view of the breakers, the third shows the panel wiring. It appears that I have 125 amp service since that's how the main disconnect breaker is labeled. It looks like there are three sets of ganged 40 amp breakers supplying the cooktop, double ovens, and air conditioner. There's two ganged 30 amp breakers supplying the clothes dryer, and up at the top, two ganged 25 amp breakers supplying a "wall heater" which I don't have. The house was built about 30 years ago. I assume that all the ganged breakers are supplying 230 volts to their respective device, but with the exception of the dryer, I can't actually see the plugins.

Need some advice: What do I have? What can I do to add the new circuit? I'm sure I'll be advised to hire an Electrician, but I'd like to be armed with the right questions and good answers...

 

[Norcal]

Your panel is stuffed with twin breakers, there is no more space, some circuits will have to be moved to a new subpanel or have a service change done, which will be fun since it's a semi-flush panel in what looks to be stucco. Is the main 100 or 125A?


Edit: since I scanned the post, if there is a unused circuit, that just might be able to work.

 

[theoldwizard1]

... I assume that all the ganged breakers are supplying 230 volts to their respective device, but with the exception of the dryer, I can't actually see the plugins.

Correct.

One question. Have you ever tripped the main breaker while running the AC, stove, and dryer and other appliance simultaneously ? I'm guessing no.

While you do have quite a few circuits for a 125A service, I would not be concerned about swapping out 4 of the 120V breakers for 2 tandem breakers (a tandem breaker is 2 independent breakers that only take 1 slot). That will give you 2 more slots for a 240V 30A breaker.

The worst thing that MIGHT happen is tripping the main whenyou are using the welder, the AC is on and the wife is cooking a roast and doing laundry all at the same time. Possible, but not likely. If it does happen, don't start welding until after dinner !

If you have done other wiring, this is not that difficult of a job. I swapped in 4 tandems in a 100A load center at my daughters house because I needed 4 additional circuits for a kitchen remodel.

 

[nehog]

That unused double breaker is how many amps? If not the right amperage just replace it with a correctly rated breaker and you should be OK.

 

[theoldwizard1]

... there is no more space, some circuits will have to be moved to a new subpanel or have a service change done, ...

Forget the subpanel. Regardless what any electrician tells you, it is not worth the money.

If you are currently having issues tripping the main, it is time for a 200A load center and an upgrade of the incoming power line. This would be big $$$ !

 

[theoldwizard1]

That unused double breaker is how many amps?

I assume you are looking at slots 5-8. Aren't those the main ?

 

[Vista]

Thanks for the inputs. You're dealing with an electrical "rookie" here. I've basically rewired my garage, but that was largely extending existing circuits. What I need to know is what type and size of wire is needed, what kinds of boxes and plugs, etc.? Do I need to have a panel or shutoff switch inside the garage?

I assume I have 125 amp service because the ganged "Service Disconnect" breakers have "125" on one of the handles (#5 and #6 down on the left photo). It may just be a 100 amp service...how do I tell?

For info, I do not have a trash compactor (#10 up from the bottom). I'm going to trip the ganged 25 amp breakers (#2 and#3) marked as "Heater (wall)" to see what happens. This might be a good source for the welder 230 V.

 

[theoldwizard1]

Thanks for the inputs. You're dealing with an electrical "rookie" here. I've basically rewired my garage, but that was largely extending existing circuits. What I need to know is what type and size of wire is needed, what kinds of boxes and plugs, etc.? Do I need to have a panel or shutoff switch inside the garage?

If you goal is to only add 1 230V circuit to your garage you do not need a panel or shutoff.

The size and type of wire depend on the load (how many amps does the welder pull) and the distance from the panel to the welder receptacle. This will also dictate the type of plug.

I assume I have 125 amp service because the ganged "Service Disconnect" breakers have "125" on one of the handles (#5 and #6 down on the left photo). It may just be a 100 amp service...how do I tell?

If the mains say 125A, then you have 125A "service".

I'm going to trip the ganged 25 amp breakers (#2 and#3) marked as "Heater (wall)" to see what happens. This might be a good source for the welder 230 V.

You maybe be in luck, but I will bet your welder needs at least 30A and possibly 50A. Simple breaker swap.

 

[Vista]

After some breaker-trippin' research, I've discovered that the ganged 25 amp breakers that I thought might be spare, are in fact supplying 230v power to an in wall heat pump A/C unit that was installed 4 or 5 years ago. The breakers were labeled "Heater (wall)" I rarely run that unit, so that might be a source of welder power. Can a wire just be run into the panel and hooked to those breaker leads? The welders I have in mind draw 20-22 amps at rated load. Is it advisable to replace the 25a breakers with 30a?

I've never had the main breakers trip, though we have had some breakers trip in the kitchen during heavy Thanksgiving cooking loads. I also found that the breaker labeled "Trash compactor" supplies a kitchen plug that currently feeds our toaster oven. I can't find anything that loses power when the breaker labeled "FAU GFI" is tripped - I assume GFI stands for ground fault interrupter, but what does FAU mean?

 

[MrMark]

forced air unit.

You would be better off in the long run to put in a nice 40 space subpanel on the inside of that wall and transfer all the circuits to that new panel. You could leave the existing combo panel simply to feed to subpanel. That main combo is antiquated and in bad shape.

 

[theoldwizard1]

The breakers were labeled "Heater (wall)" I rarely run that unit, so that might be a source of welder power. Can a wire just be run into the panel and hooked to those breaker leads?

No. It is hard wired to something so it can not be shared.

The welders I have in mind draw 20-22 amps at rated load. Is it advisable to replace the 25a breakers with 30a?

I would go 30A. 240V plugs and receptacles are either rated for 20A or 30A, but it will still have to be a separate circuit.

 

[theoldwizard1]

You would be better off in the long run to put in a nice 40 space subpanel on the inside of that wall and transfer all the circuits to that new panel. You could leave the existing combo panel simply to feed to subpanel. That main combo is antiquated and in bad shape.

Antiquated ? Yeah, its old.

Bad shape ? I don't know how you came to that conclusion.


Yes, the best solution would be to install a new 200A service with a lot more spaces. Is this cost effective ? Not in my opinion.

Is swapping in a couple of tandem breakers safe ? Yes, as long as tandem breakers are available from the manufacturer.

 

[Bib Overalls]

If possible, I would put a 60 amp, 6 space sub-pane on the interior wall immediately behind your main panel and connect the two with a short metallic conduit. 1 inch or larger. Then I would wire 4 existing tandem breakers circuits into the new panel through the conduit. This will clear two spaces for a 60 amp double breaker to supply the sub-panel. Wire your welder outlets through conduit. You did not mention an air compressor but I would suspect you will want a 230V for one at some point.

FYI a "quad" circuit breaker like the one in the link can be a cost efficient solution to adding a 230V circuit when a pannel is full.

http://www.ebay.com/itm/Cutler-Hamm...A%2BFICS%2BUFI&otn=21&pmod=290826910337&ps=54

 

[theoldwizard1]

FYI a "quad" circuit breaker like the one in the link can be a cost efficient solution to adding a 230V circuit when a pannel is full.

http://www.ebay.com/itm/Cutler-Hamm...A%2BFICS%2BUFI&otn=21&pmod=290826910337&ps=54

That's a cool solution to this very problem if that type of breaker is available from the panel manufacturer !

The Square D QO version replace 2-120V breakers with with 1-240V breaker and 2-120V breakers.

 

[5mall5nail5]

That's a cool solution to this very problem if that type of breaker is available from the panel manufacturer !

The Square D QO version replace 2-120V breakers with with 1-240V breaker and 2-120V breakers.

Whoa... that's cool.

 

[Norcal]

That's a cool solution to this very problem if that type of breaker is available from the panel manufacturer !

The Square D QO version replace 2-120V breakers with with 1-240V breaker and 2-120V breakers.

Guess what. Only GE THQP 1/2" breakers fit the OP's panel, THQP also will not fit any other make. SQ D HOM is not UL classified to fit any make except SQ D Homeline.

In case anyone asks, THQL full size fits too just no spots for them.

THQL = GE 1" plug in breaker.

THQB = GE 1" bolt on breaker. Not normally used in residential.

THQP = GE 1/2" plug in breaker.

 

[mr-compressor]

WOW... I just have 40 amps for my whole house in total!

 

[theoldwizard1]

Guess what. Only GE THQP 1/2" breakers fit the OP's panel, ...

Which is why I said "... as long as tandem breakers are available from the manufacturer."

 

[Bib Overalls]

WOW... I just have 40 amps for my whole house in total!

Not unusual. I have seen old farm houses with two 15 amp fuses. One for lights and one for the radio so they could listen to FDR's fireside chats.

 

[theoldwizard1]

Only GE THQP 1/2" breakers fit the OP's panel, ...

Okay, so GE does not make quad breakers. The GE THQP "thin" breakers take 1/2 of a slot. They also make 2 pole (240V) "thin" breaker take 1 slot (must 1/2 on each of 2 different slots).

Pull 2 of the existing 1 pole "standard" size breakers and replace them with 2 thin 1 pole and 1 thin 2 pole. Same net effect.

 

[Aceman]

That's a cool solution to this very problem if that type of breaker is available from the panel manufacturer !

The Square D QO version replace 2-120V breakers with with 1-240V breaker and 2-120V breakers.

That's a Homeline breaker. When I've asked my Sq D dealer in the past, he told me they don't make QO quads. Just one more reason I use Siemens.

 

[Vista]

Thanks again for the info and advice. After further research on this site, and particularly on a couple of welding sites, I've decided to make a 50-foot extension cord to hook the welder to my clothes dryer receptacle. As you can see from the attached pic, the dryer is just inside the door into the garage and the overhead door out to the driveway. I can get all the necessary components at Lowe's, for a cost of about $125.

Vista

 

[pattenp]

Just remember you don't need the neutral that the dryer has so just get 3 conductor cord (2 hots and ground).

 

[pattenp]

You're wrong if you are thinking of splitting off a 15/20A 120V outlet for the welding cart from a 30A or more 120/240V cord without having overcurrent protection for the 15/20A 120V outlet.

Get the four wire anyway. You might upgrade welders and need a water cooler or some other 110 gizmo. Plug welding cart in to extension cord, wire cart for 220/110.

I went for the extension cord in the little garagr. Makes life easy and i can trot the welder out to the drive way easily.


Or I'm horribly wrong.

 

[Aceman]

Get the four wire anyway. You might upgrade welders and need a water cooler or some other 110 gizmo. Plug welding cart in to extension cord, wire cart for 220/110.

I went for the extension cord in the little garagr. Makes life easy and i can trot the welder out to the drive way easily.


Or I'm horribly wrong.

Yep, the last one.

 

[theoldwizard1]

That's a Homeline breaker. When I've asked my Sq D dealer in the past, he told me they don't make QO quads. Just one more reason I use Siemens.

You are correct.

What your dealer should have told you is on page 1-2 of the Square D catalog

2P—120/240 VAC Common Trip (i.e. quad)

Order two QOT1515 or QOT2020 tandem circuit breakers and handle tie QOTHT for common switching of center two poles.

 

[theoldwizard1]

After further research on this site, and particularly on a couple of welding sites, I've decided to make a 50-foot extension cord to hook the welder to my clothes dryer receptacle.

Good solution especially with the receptacle so close to the garage.

Because welder use, especially in a home setting, has a very low duty cycle (the ratio of ON time to OFF time) you are not likely to overheat a properly sized cord.