Residential wire question.

[Chadwilliam1]

I have a 100 amp sub panel in my attached garage. 200 amp main. My garage is 32x24 and I have my air compressor and welder are both 240. Right now I have a 30 amp breaker ran to the opposite side of my garage for the two items.

I want to run 6-3 wire to the side of my garage. I want to cut through the drywall and run it through the studs and then patch it.

My question is how can I wire these two items. My compressor draws 22 amps and my welder draws 50 at best. I never weld with it all the way up. So a 6-3 wire is good for 65 amps I believe. I want to make sure I have enough power for those two items. I don't usually weld and my compressor running at the same time any way.

What kind of box should I mount? I want it to be flush mounted. Do I need another sub panel?

Thanks
Chad

Sent from my 2PS64 using Tapatalk

 

[grantw]

Be aware some AHJs don't allow multiple outlets on circuits above >20A... There was another thread on this board awhile ago about pretty much what you're asking.

Joining #6 wire for multiple outlets may not be a great way to go... If you are running holes in studs, get a quad breaker, and run two home runs. nail plates if you don't bore deep enough.

 

[Chadwilliam1]

Could I just add a 4 breaker sub panel? My sub panel in my garage only holds 8 and I have 5 spots taken already.

Sent from my 2PS64 using Tapatalk

 

[grantw]

I don't see why not. A small sub-sub-panel should be fine. Don't bond the neutral and ground, and you will be fine.

 

[Chadwilliam1]

Thanks.

Sent from my 2PS64 using Tapatalk

 

[wyliesdiesels]

What is the horsepower rating on the compressor?

If it's over 3hp, to be code compliant, it should be hardwired. It sounds like you have a 5hp motor.

The wire for motor circuits is sized at 125% of the NEC table FLC not the nameplate amps/FLA

The welder and compressor should be on different circuits due to the difference with input requirements.

Nm-b 6-3 is rated at 55a (60* c column).

A subpanel will be the best

 

[sberry]

Put a 6 space sub on it, you can stop or not weld with the comp running and many of the modern welders run with 25A wide open.

 

[Chadwilliam1]

Right now my compressor is hard wired and yes it is a 5 horse running. So I should run 4-3 ?

Sent from my 2PS64 using Tapatalk

 

[Crazyjake8493]

Could I just add a 4 breaker sub panel? My sub panel in my garage only holds 8 and I have 5 spots taken already.

Sent from my 2PS64 using Tapatalk

Could you combine two existing breakers into a tandem breaker? That would free up a 4th spot, with enough room for 2 double-pole breakers. Unless you plan on adding more circuits later on.

 

[Chadwilliam1]

I could. I do not plan on adding in more circuits at the moment. I think this route you are suggesting is my cheaper option. This house is 2 years old and when they gave me the prints I picked a spot for the sub panel. Not realizing the place I chose I would not be able to pull wire unless I went over a few feet and then up. Because there is a bedroom above.

So if I ran another panel to the other side with a few more breakers. If I needed to pull another circuit I could then go straight up and into the attic. Right now I have three extra spaces in my sub panel but when I cut access last year and ran all of my circuits I ran 6 of them in to the attic and then ran them to outlets through out the garage. I am only using four of them the other two I ran into the attic as spares and not hooked up on either side. Just in case I need them later. I can not forsee a situation where I would ever need that much power at once.

I should have moved the panel when I first moved in.

Sent from my HTC 10

 

[bjcouche]

I think you've got us confused. If your air compressor is already hardwired, why are you asking us how to wire it? Are you just asking us how to wire your welder? What's the nameplate horsepower of the compressor? You said it's a 30A circuit, is it also 10awg wire? Based on the nameplate horsepower of the compressor, 30A or 10awg might be OK or undersized per code. Also, can you get a picture of the welder nameplate? Welder circuits have special wiring and breaker size exceptions in the NEC due to their low duty cycles. If your existing subpanel in the garage is too full, I'd just replace it with a bigger one instead of adding a second one in your size garage.

 

[Chadwilliam1]

I shouldnt have typed my original post on my phone. I have 3/4 conduit ran accross the wall of my garage. I want to hide it and put it behind the drywall. At the end of the conduit I have a metal box with a 50 amp plug and also I have 10 gauge romex coming out going to the compressor. So If I weld I can sht off the compressor and weld.

When I weld which is not often I am rather low on the settings not even going past the 50% mark of what the welder can do.

Here is a link to the welder I have it is a lincoln tombstone welder.
https://www.google.com/search?q=lin...UICigD&biw=1364&bih=613#imgrc=20gcTGmyqEsH_M:

Thanks




https://www.google.com/search?q=lin...UICigD&biw=1364&bih=613#imgrc=20gcTGmyqEsH_M:

 

[alfredeneuman]

I believe Ohio uses the ICC Codes
Under the International Electrical Code, you can't have multiple outlets on a circuit larger than 20Amps
There is no such limitation under the NEC.

Better opt for the subpanel

 

[wyliesdiesels]

If your compressor is truly 5HP(which 22a FLA is most likely) then u need #10 thwn or #8/2 NM-b/Romex. It should be hardwired unless u can find an outlet rated for at least 5HP

The welder needs a 50a breaker and outlet but the wiring can be reduced based on duty cycle of welder.

Due to different circuit requirements the easiest thing to do is a subpanel.

 

[bjcouche]

Wyliesdiesels told you what you need for wire for the air compressor and I concur.
Now for the Welder, according to the Lincoln AC-225 manuals I find online, it is rated for 50A input and a 20% duty cycle. This means you'll need a 50A breaker supplying power to your welder outlet. However for the wire, the NEC has special allowances for under sizing it based on the duty cycle. Per NEC table 630.11(A) 20% duty cycle is a multiplier of 0.45. 0.45*50=22.5A. 12awg is rated for 25A (table 310.16) at 60C, so you could use 12awg NM-b on a 50A breaker to your dedicated welder outlet. If it were me though I'd use 10awg in case the welder is swapped out for a higher duty cycle, and to minimize voltage drop. Or if I had leftover 8/2 NM-B from wiring the compressor, I'd use that.

 

[wyliesdiesels]

If you perceive ever using that 50 amp outlet for anything other than the welder, then I would not use reduced size wire. Instead go with 6/3 NM-b wire

 

[sberry]

The 12 is single circuit in pipe I believe for that machine. But it pulls 40A at 120A. That's really as far as I turn them up, at rated output it pulls 48. No one thinks this minimum is a good idea and I would buy the 12/30 for a 200 mig though as far as wire goes nut some of the recepts are only listed to 10 today as I recall and the V drop is substantially less on a 10 than a 12 with a buzzer. U can run one till its a cinder and not overheat a 10 cable with only 3 v drop or so over 25 ft, 12 is probably well over 10. I have ran them wayyyyyyy past 20%

 

[sberry]

What might we plan on putting on this welder circuit in the future? Spose we could under wire a tig or machine to it that doesn't come factory plug. A range is 4 wire anymore, spose a kiln or some specific oven could be 2 wire though. Somehow this must not be much of a problem or they would make a law?

 

[Chadwilliam1]

Thanks for everybody's help. I plan on replacing my main sub panel with a larger box and then running down to the other side with another panel.

For the first sub panel is there any reason not to just mount a regular breaker panel with a main in it?

Sent from my HTC 10

 

[sberry]

You can have a main in a sub.

 

[Chadwilliam1]

Replaced the first sub panel today with 20 space 100 amp. I removed the bonding band. I have neutral on one side and ground on the other.

What would happen if when wiring up a circuit I put a neutral on the ground side?

Sent from my HTC 10

 

[wyliesdiesels]

Replaced the first sub panel today with 20 space 100 amp. I removed the bonding band. I have neutral on one side and ground on the other.

What would happen if when wiring up a circuit I put a neutral on the ground side?

Sent from my HTC 10

You could and will have neutral return currents flowing on pathways that you don't want them flowing on.

 

[Chadwilliam1]

Thank you.
I didn't do it but was curious because some of my wires are a little short but it works.

Sent from my HTC 10

 

[sberry]

This is the whole point of 4 wire feeds, insulate the neutral currents. We want to eliminate the potential to have current flowing on frames or other equipment.

 

[Chadwilliam1]

So if I want to put a longer cord or make an extension cord for my welder using 12 gauge would be OK?

Sent from my HTC 10

 

[bob_mp]

My question is how can I wire these two items. My compressor draws 22 amps and my welder draws 50 at best. I never weld with it all the way up. So a 6-3 wire is good for 65 amps I believe. I want to make sure I have enough power for those two items. I don't usually weld and my compressor running at the same time any way.

Sent from my 2PS64 using Tapatalk

The current drawn from variable mutual-inductance (buzz-box) welder is a weak function of welding current. The inner product of current and voltage (power delivered) varies considerably, but the current doesn't. What varies is the angle between current and voltage. That you never weld with max current on your welder may do very little to reduce the current drawn by the welder.

Current is what trips breakers, not power delivered.

Bob

 

[nadogail]

So if I want to put a longer cord or make an extension cord for my welder using 12 gauge would be OK?

Sent from my HTC 10

What is the full load current draw of your welder? IMHO, if it is 20 Amps or less, 12 gauge should be OK.