Garage Circuit help

[ex_nihilo]

My garage currently only has 120 available. I am in the process of rewiring a saw motor and a compressor motor to 240v.
The saw will draw 6.5 amps and the compressor motor will draw 11 amps.
I have 6R-15 plugs on both of them.
The total length of wire in the new circuit is about 30 feet.
I would normally use 12 gauge wire and a 20 amp breaker, but since there is a chance I might upgrade to a higher amp compressor motor, is it okay if I go ahead and use 10 gauge wire and a 30 amp breaker? Or should I run the 10 gauge wire and use a 20 amp breaker?
My receptacles are going to be 6-20r.

Any advice is greatly appreciated.
Cheers

 

[Norcal]

You can’t use a 20A receptacle on a 30A circuit.

 

[wyliesdiesels]

how are you gonna run 240v equipment on a 120v branch circuit?

lotta questions on this one...

 

[ex_nihilo]

how are you gonna run 240v equipment on a 120v branch circuit?

lotta questions on this one...

The new circuit is 240v.

 

[ex_nihilo]

You can’t use a 20A receptacle on a 30A circuit.

Great thanks.

So, I'll use 30 feet of 12/2 with two 6-20 receptacles and a 20 amp breaker.

 

[wyliesdiesels]

is the garage attached or detached?

 

[ex_nihilo]

is the garage attached or detached?

It's attached.

 

[dcg9381]

You can’t use a 20A receptacle on a 30A circuit.

That's correct.. But for what the OP wants - which is future upgrade - I'd run 10ga wire, just on a 20A circuit:

Most 20A outlets will take 10ga wire. What makes it a 30A circuit is the breaker... So 20A breaker, 10ga wire, 20A outlet is OK - it's a 20A circuit... This way it's simple to upgrade to a 240V outlet with an outlet change and breaker change.


What I can't tell is if he can do a 30A branch circuit in a non-dwelling for purposes other than lighting.. NEC 210.23(B)

 

[ex_nihilo]

That's correct.. But for what the OP wants - which is future upgrade - I'd run 10ga wire, just on a 20A circuit:

Most 20A outlets will take 10ga wire. What makes it a 30A circuit is the breaker... So 20A breaker, 10ga wire, 20A outlet is OK... This way it's simple to upgrade to a 240V outlet with an outlet change and breaker change.

Yessir. This is what I was thinking initially.

But, in order to have to only do this once and utilize the whole circuit: Could I run a 30 amp circuit but use a 6-30p to 6-20r adapter plug for my machines that are wired with a 6-15p cord?
Is this a bad ideer? Thanks for all your help and advise.
Cheers!

 

[u2slow]

A few 6-20R's on #12 is a handy shop circuit. I even cheat some 120V receptacles on it.

If/when you need to go bigger, run a dedicated circuit at that time, based on the equipment's requirements.

 

[infinkc]

Just thinking out loud here, not sure if you would ever consider an electric car down the road, but i see so many people jumping ship and getting one. You may want to run a larger circuit to support 40A if you ever do decide to charge a car/rv

 

[Terry D]

A few 6-20R's on #12 is a handy shop circuit. I even cheat some 120V receptacles on it.

If/when you need to go bigger, run a dedicated circuit at that time, based on the equipment's requirements.

You can not safely get 120 volts out of a circuit for 6-20r devices. There is no grounded conductor. The only way to do this is to use the equipment ground, which is a code violation and a safety issue. He would need to run a 120 volt circuit for 120 volt receptacles.

 

[u2slow]

You can not safely get 120 volts out of a circuit for 6-20r devices. There is no grounded conductor. The only way to do this is to use the equipment ground, which is a code violation and a safety issue. He would need to run a 120 volt circuit for 120 volt receptacles.

Nonsense. I use a #12/3 cable with a neutral.

 

[Terry D]

Nonsense. I use a #12/3 cable with a neutral.

But the OP is using 12/2. Even with 12/3, that really isn't the right way by tapping off one leg.

 

[dcg9381]

But, in order to have to only do this once and utilize the whole circuit: Could I run a 30 amp circuit but use a 6-30p to 6-20r adapter plug for my machines that are wired with a 6-15p cord?
Is this a bad ideer? Thanks for all your help and advise.
Cheers!

Depends on who you ask. My MIG welder is setup with a 14-50P even though it's not going to pull more than about 20A. Wall socket is 14-50R, 10 ga wire, 30A breaker. Technically I need to label the outlets "welder, 30A".

Because I have a few spots for RVs, I've basically standardized on the 14-50P outlet. My welding setup is mobile (fits on the front of a UTV) - so this gives me a lot of flexibility.

Just thinking out loud here, not sure if you would ever consider an electric car down the road, but i see so many people jumping ship and getting one. You may want to run a larger circuit to support 40A if you ever do decide to charge a car/rv

Per my electrician, he recommends you use wire capable of 60A for EV. That way running it at 40A actual - you can do that all day long.