adding a 240 curcuit to my garage

[Jslys13]

I would like to add a 240v outlet to my garage. The bad part is my 100 amp box is full. And most breaker are already tandem breakers. The new circuit just needs to be 20 amps. Itsseems for a new table saw I plan to purchase. What's my best option. i would like to upgrade to a 200 amp service but that's not gonna happen right now. Is there a way to make an extension cord and run it off my dryer outlet? Thanks in advance

 

[theoldwizard1]

If you can not install more tandem breakers, then you will have to install a new panel, or a sub-panel immediately next to the original.

6 slot/12 circuit main lug sub-panels are cheap (< $20), but you should buy one that uses the same breakers as the other box. You will have to move 2 slot to the new box so effectively you will only have 4 open slots (8 circuits).

 

[sberry]

They make an 8 space in the same can as a 6 just for this.

 

[wyliesdiesels]

I would like to add a 240v outlet to my garage. The bad part is my 100 amp box is full. And most breaker are already tandem breakers. The new circuit just needs to be 20 amps. Itsseems for a new table saw I plan to purchase. What's my best option. i would like to upgrade to a 200 amp service but that's not gonna happen right now. Is there a way to make an extension cord and run it off my dryer outlet? Thanks in advance

nope

 

[nadogail]

You Wrote "Is there a way to make an extension cord and run it off my dryer outlet?"

With respect to the previous poster from Modesto; I may be full of s**t, but an awful lot of weldors run small welders from clothes dryer receptacles.

I used to run my saw from the dryer outlet, we just could not do laundry and make sawdust at the same time.

I worked until we moved and I could put in a branch circuit for the saw.

 

[theoldwizard1]

You Wrote "Is there a way to make an extension cord and run it off my dryer outlet?"

With respect to the previous poster from Modesto; I may be full of s**t, but an awful lot of weldors run small welders from clothes dryer receptacles.

Again, respect to Wylie, but yes, you can make an extension cord to run off of a dryer outlet. Obviously this is not a permanent installation which is what the OP was first inquiring about !

For a 20A extension cord, you should use 10AWG SJOOW (or SOOW) cordage with the appropriate good quality connectors on each end. 25' of 10/3 SJOOW is about $50 on eBay. If you have to go over 50', you probably should go to 8AWG.

 

[wyliesdiesels]

You Wrote "Is there a way to make an extension cord and run it off my dryer outlet?"

With respect to the previous poster from Modesto; I may be full of s**t, but an awful lot of weldors run small welders from clothes dryer receptacles.

I used to run my saw from the dryer outlet, we just could not do laundry and make sawdust at the same time.

I worked until we moved and I could put in a branch circuit for the saw.

Again, respect to Wylie, but yes, you can make an extension cord to run off of a dryer outlet. Obviously this is not a permanent installation which is what the OP was first inquiring about !

For a 20A extension cord, you should use 10AWG SJOOW (or SOOW) cordage with the appropriate good quality connectors on each end. 25' of 10/3 SJOOW is about $50 on eBay. If you have to go over 50', you probably should go to 8AWG.

Both of you failed to bring up the issues with grounding and whether the dryer outlet is a 3-wire or 4-wire outlet. If 3-wire and fed off a subpanel then u would have issues using an adapter. Its not as simple as just making an adapter as both of u think.

The other issue is the saw needs a 6-20r which is rated for 20a and thus shouldnt be used on a dryer circuit which is 30a.

Sure, u could do it. However, not only would it violate code but it can also be a hazard...

This is why i said no....

 

[theoldwizard1]

The other issue is the saw needs a 6-20r which is rated for 20a and thus shouldnt be used on a dryer circuit which is 30a.

This would be my biggest concern.

 

[Whitworth]

Assuming a non-permenant situation, just make an extension cord. Use romex, 10 gauge and whatever NEMA male and female connections your situation requires. Done all the time running juice at construction sites. Just be careful of the wire that you don't flex it excessively.
If it's a short run you could probably get away with using 12 gauge.

 

[wyliesdiesels]

#12 on a 30a breaker? Really? Comeon...

 

[Whitworth]

Extension cords are not sized by breaker. 12 gauge wire wouldn't be on the breaker. It would plug into the dryer receptacle. By your logic I would need a 12 gauge cord on a 20 amp circuit to plug in my Christmas tree lights !

 

[theoldwizard1]

The purpose of the breaker is to

1. protect the wire
2. protect the appliance

The reason the wire is first priority, it is typically more difficult/expensive to replace and likely has a higher probability of starting a fire.

Extension cords are typically down rate because of the abuse they see over time. Higher probability of one or more strands breaking.

If you built in some kind of a fuse/breaker box near the male end of the cord that had 2 - 20A breakers, then a 10 gauge cord would be protected when plugged into a 240V 30/50A circuit. It might not meet the letter of the law, but it certainly meets the spirit.

Extension cords are not sized by breaker.

But they probably should be !

The NEC is a bit odd on 15A/20A circuits is residential buildings. No requirement for 20A receptacle, even though 20A circuit are required is several residential location. (Of course, when has anyone seen a 120V home appliance that draw over 15RLA and has a 5-20 plug on it ?)

I would need a 12 gauge cord on a 20 amp circuit to plug in my Christmas tree lights !

Technically, yes. This is part of the oddity of the code. You can plug a 20A appliance into a lamp extension cord (rated at less than 15A) and into a 20A receptacle and circuit. In that case the extension cord is the fuse !

 

[Whitworth]

Btw, they do have high voltage extension cords for industry and the trades. They are a bit pricey and I don't know if there's much variety on what NEMA style of plug is available. There's also extension cords used for RVs, which I imagine consume quite a few watts.

I think the OP just needs a temporary set up for his saw. In the long run a permenent solution like a sub panel for the garage is what should be done.

 

[wyliesdiesels]

Extension cords are not sized by breaker. 12 gauge wire wouldn't be on the breaker. It would plug into the dryer receptacle. By your logic I would need a 12 gauge cord on a 20 amp circuit to plug in my Christmas tree lights !

I know that, Im an electrician.

However, when u have seen as many burned up extension cords as i have, u would NOT be putting a #12 extension cord on a 30a circuit. Waste of money and time if u toast the cord AND a fire hazard!

 

[wyliesdiesels]

The purpose of the breaker is to

1. protect the wire
2. protect the appliance

The reason the wire is first priority, it is typically more difficult/expensive to replace and likely has a higher probability of starting a fire.

Extension cords are typically down rate because of the abuse they see over time. Higher probability of one or more strands breaking.

If you built in some kind of a fuse/breaker box near the male end of the cord that had 2 - 20A breakers, then a 10 gauge cord would be protected when plugged into a 240V 30/50A circuit. It might not meet the letter of the law, but it certainly meets the spirit.

But they probably should be !

The NEC is a bit odd on 15A/20A circuits is residential buildings. No requirement for 20A receptacle, even though 20A circuit are required is several residential location. (Of course, when has anyone seen a 120V home appliance that draw over 15RLA and has a 5-20 plug on it ?)

Technically, yes. This is part of the oddity of the code. You can plug a 20A appliance into a lamp extension cord (rated at less than 15A) and into a 20A receptacle and circuit. In that case the extension cord is the fuse !

Actually, the putpose of breakers is to protect the building wire NOT whats plugged into the circuit. Refrigeration equipment has overloads on them, christmas tree lights have fuses, etc.

and your last paragraph makes no sense. Explain to me how one would plug a 20a appliance(with a 5-20p), other than by twisting the neutral blade sideways, into a 15a or less rated cord that has a 5-15r?

 

[theoldwizard1]

[/b]
...and your last paragraph makes no sense. Explain to me how one would plug a 20a appliance(with a 5-20p) into a 15a or less rated cord that has a 5-15r?

Are 20A appliances required to have 5-20P on them ?

If so then my statement is INCORRECT.

 

[wyliesdiesels]

Are 20A appliances required to have 5-20P on them ?

If so then my statement is INCORRECT.

Yes they are because the load is more than 15a...