Breaker ?

[jaker10]

How many amps can I safely pull from a 20 amp breaker? I have a 220 volt air compressor that is tagged 13 amp. I also have a 220 volt grinder that is tagged 3.3 amp. Can both run on a 20 amp breaker. Wire is rated at 20 amp. I think the wire is 12 2 but would have to look to make sure. So is 16.3 safe on 20 amp breaker?

 

[kd3pc]

as long as your wiring and receptacle are in good repair you should be just fine.

 

[jaker10]

Thanks, and have a merry Christmas.

 

[wyliesdiesels]

How many horse is the compressor?

A continuos load is sized at 125% and therefore the continous load on a circuit should never be more than 80% of circuit capacity. This means 16a.

The compressor should really be on its own circuit due to in rush currents...

 

[jaker10]

How many horse is the compressor?

A continuos load is sized at 125% and therefore the continous load on a circuit should never be more than 80% of circuit capacity. This means 16a.

The compressor should really be on its own circuit due to in rush currents...

Compressor says 13 amp and owners manual says 15 amp minimum branch circuit requirement. Manual says 3.2 HP. I'm running it off a 20 amp breaker. Grinder is 1/2 HP and 3.3 amp

 

[Speedy Petey]

You are FINE with these two on a 20A circuit. Neither is even close to a continuous load, and even if the compressor starts while running the grinder the breaker should be ok handling the temporary startup current.

 

[sberry]

I agree. I am sure the grinder is designed to be able to run from a 20. If it came with a factory cord and is a 14 may be able to run on 30A in a certain environment.

 

[Speedy Petey]

I agree. I am sure the grinder is designed to be able to run from a 20. If it came with a factory cord and is a 14 may be able to run on 30A in a certain environment.

In that case it'd need a 30A attachment plug or be hard wired, which is highly unlikely for a 1/2hp grinder.

 

[sberry]

I was wondering if it came with a factory plug? Most of that small stuff is 120 even though it can be wired either voltage. I was just generalizing anyway, you do see this in woodworking shops which often have multiple machines on a circuit.
Units that have no additional overcurrent are limited to the size breaker they may be connected to. If its got a 16 wire needs to be limited to a 15 or 20A. Obviously this is simplification and very general.

 

[jaker10]

This is an old grinder made in 1957, don't know if it came with a plug . But it's got one on it now. The air compressor say to hard wire it.

 

[Norcal]

Those old Rockwell grinders are nice machines, have a couple of early 1970's era ones, myself. Unless your circuit breakers are made by Federal Pacific Electric, I would not worry about the grinder & compressor being on the same circuit.