[timothale]

The national elect code is a guide and states counties or cities can adopt the codes..ELECT, BUILDING, PLUMBING. ETC and the goverenment agencies can make additional rules.

[scotzz]

Originally Posted by 1ownerT

Maybe I read post #32 wrong. I read it that one is unplugged and the other is plugged in as needed.

That is correct and I emphasize again that[B]only one of two plugs can be in the existing dryer receptical.[/B]...........either the dryer lead or.......the lead for the garage line extension. Think of this way.......it would be similar to having two dryers side by side.........I could only have one plugged in at a time. The receptical for the dryer is correct for the dryer and has a different pin configuration than the 240v receptical in the garage.

[roger1]

Originally Posted by scotzz

That is correct and I emphasize again that[B]only one of two plugs can be in the existing dryer receptical.[/B]...........either the dryer lead or.......the lead for the garage line extension. Think of this way.......it would be similar to having two dryers side by side.........I could only have one plugged in at a time. The receptical for the dryer is correct for the dryer and has a different pin configuration than the 240v receptical in the garage.

The problem is that you will be using a compressor that is a 220V 20 Amp on a 30 Amp breaker.
Not good to do.

[scotzz]

Originally Posted by roger1

The problem is that you will be using a compressor that is a 220V 20 Amp on a 30 Amp breaker.
Not good to do.

Actually I will be using a welder that draws 20A. Why is this any different than an appliance/TV/lamp/etc that draws only a few amps from a 120v, 15A line?

[woodz428]

I reread the extra context that you felt was missing..now in your and Bullheimers area that may be the case...however the comment wasn't about new houses in his or your area it was EVERY new house. I just happen to know that locally that is NOT true. It is unacceptable locally, that would eliminate EVERY new house. It is not allowed in any service, I don't care whether it is entrance or range service it is NOT allowed. I also made sure that I stated that I wasn't sure whether it was a National or local. So it apparently isn't National, but I am more than aware of local ordinances, several of my good friends are master electricians as well as my son-in-law. That's the main reason I suggest checking your local building codes. Since this is really an International forum some things aren't universally applied. I know that Rods/Custom builds are pretty easy to register here in Illinois, I do it regularly, but I wouldn't even want to try it in Ca., or some other states....Ca. is the most notorious that's why I mentioned it specificly. I have no personal opinion on the Al. wiring,I do know that inspectors can be tough. So it's always better to be informed of local standards. NOW, as a caveat, some stuff done by the homeowner on their own, doesn't require certain things...like a licensed electrician...but, I think stuff like wiring standards still have to be met.

[bluesman2333]

Originally Posted by roger1

The problem is that you will be using a compressor that is a 220V 20 Amp on a 30 Amp breaker.
Not good to do.

No, the problem is having two different loads on one dedicated circuit.

[bluesman2333]

Originally Posted by woodz428

... I think stuff like wiring standards still have to be met.

The code is the code and good practice and correct installation procedure and techniques still apply to everyone, homeowner and electrician alike.

Getting back to fire insurance, when a fire occurs and the homeowner wired a circuit that causes a fire, the homeowners insurance may not cover the fire. I would say will not, but I'm sure somewhere there is an exception.

The other side of the coin is why skimp to save a few bucks when the stakes are so high? Would you skimp on the size of your brake lines or take a chance on running bald tires on the highway with your family in the car?

Why do it with a circuit in your garage?

[woodz428]

Originally Posted by bluesman2333

The code is the code and good practice and correct installation procedure and techniques still apply to everyone, homeowner and electrician alike.

I agree fully. the NEC is a minimum code acceptable, and local communities can and do elevate(at least in their mind) any National code. That is the reason I suggested checking the code in whatever location you reside. I don't think you wil find any disagrement on folowing code. I have at least $500,000 of vehicles in my shop at any given time, sometimes a single car of that value( Shelbys are through the roof). I have always found it easier to avoid problems than clean up afterward.

[roger1]

Originally Posted by bluesman2333

No, the problem is having two different loads on one dedicated circuit.

To my understanding, he has a 30 Amp receptacle that is dedicated running #10 wire with a 2 pole 30 Amp breaker.

He will either plug a 30 Amp dryer into this receptacle or unplug the dryer and plug in a welder (with an extension cord) which is supposed to be on a 20 Amp 220V circuit.

So, the problem isn't what you state. And, the problem isn't running the dryer, it is running the welder on a 30 Amp breaker when it is designed for a 20 Amp circuit.
If his extension cord is #10 then he's probably running Romex as an extension cord which is not designed for that.
If he is using a standard extension cord, the largest available for those is #12 and it wouldn't be good to run #12 wire on a 30 Amp breaker.

[roger1]

Originally Posted by scotzz

Actually I will be using a welder that draws 20A. Why is this any different than an appliance/TV/lamp/etc that draws only a few amps from a 120v, 15A line?

The breaker protects the wire.
The feed cord on your 20 Amp welder will be #12 wire. It will not be protected with a 30 Amp breaker and will create a hazard even if your extension cord is #10.

[Cape Cod Bob]

How do I unsubscribe this thread , as I believe all the electricians out there have beat this to death and haven,t heard from ANGLIABOB , so his thread has been stolen !

[bluesman2333]

Originally Posted by roger1

The breaker protects the wire.
The feed cord on your 20 Amp welder will be #12 wire. It will not be protected with a 30 Amp breaker and will create a hazard even if your extension cord is #10.

You are partly correct. Cord and plug connected equipment often has a cord of a smaller gauge than the circuit ampacity. Free air amperages are higher than enclosed amperages. You shouldn't run extension cords for a variety of reasons.

These include voltage drop and overheating of plugs and cord caps due to overload from high starting currents and loose fitting connections. Plugs are by nature loose fitting, otherwise you couldn't insert or remove them.

Hooking an air compressor to a 240 volt circuit with an extension cord is not a good idea.

[Cape Cod Bob]

Found the unsubscribe , thanx.

[scotzz]

Originally Posted by roger1

The breaker protects the wire.
The feed cord on your 20 Amp welder will be #12 wire. It will not be protected with a 30 Amp breaker and will create a hazard even if your extension cord is #10.

roger1..............the specs for the welder say the power cord is a "50A, 250V, Three Prong Plug (NEMA Type 6-50P)." Input is 20A with a recommended fuse or breaker size of "40A Super Lag." Sounds confusing to me.

[bluesman2333]

Originally Posted by scotzz

roger1..............the specs for the welder say the power cord is a "50A, 250V, Three Prong Plug (NEMA Type 6-50P)." Input is 20A with a recommended fuse or breaker size of "40A Super Lag." Sounds confusing to me.

It is telling you to wire the feeder with a 40 amp circuit at a minimum. A super lag is one type of fuse that is able to withstand higher than normal inrush currents. Circuit breakers normally withstand momentary high inrush currents.

If I were you, I would give up on the shared circuit idea and wire in a separate circuit.