Making an extension cord with 10-3 wire

[countrytech]

Is this a good or bad idea?

Since my shop doesn't have electric to it, I would like to make an extension cord that I can plug into a 220 30 amp dryer outlet in my basement and then wire up a 4-outlet box at the other end with a 20 amp 110 receptacle and a 30 amp 220 receptacle so I can run a 220 air compressor and other equipment.

I already have an extra 120 ft of the orange 10-3 stuff leftover from when we built my office.

In theory this works to me, but I am not the most experienced in d.I.y. So thats why I'm asking you all.

 

[ibedayank]

Not a good idea... 10-3 is hardwire it will break not flex.
you need to run a 20amp 110 curcuit so you wont blow the breaker.
"quote" In theory this works to me, but I am not the most experienced in d.I.y. So thats why I'm asking you all."quote"

since you asked it seems you do not have the knowlage to do this safely.
Remember once you let the magic smoke out it can not be put back in. Ask yourself if it's worth losing your garage/house instead of finding and hiring somebody to do it correctly.
If done the way you plan your insureance will NOT cover anything that happens because of it!!!!

 

[ibedayank]

http://www.garagejournal.com/forum/forumdisplay.php?f=30
and you should post this here

 

[bgarrett]

Is this a good or bad idea?

Since my shop doesn't have electric to it, I would like to make an extension cord that I can plug into a 220 30 amp dryer outlet in my basement and then wire up a 4-outlet box at the other end with a 20 amp 110 receptacle and a 30 amp 220 receptacle so I can run a 220 air compressor and other equipment.

I already have an extra 120 ft of the orange 10-3 stuff leftover from when we built my office.

In theory this works to me, but I am not the most experienced in d.I.y. So thats why I'm asking you all.

When I was young and didnt have a shop, I asked the Electrician how to get power to my welder/air compressor and he told me to do what you described. It worked well for a couple of years then I built my first shop and stapled the 10-3 to the wall and continued using it .

 

[bobbycoke]

30 amp over 100feet.... I don't think so it [10/3 at 30 amps] should not be longer than 100 foot run I believe, you would need 8 gauge wire and not to be used as an extension cord but hard wired in conduit etc! Do it right, do it once...

 

[countrytech]

Hardwiring is not an option for me at this point. Much as I would love to do so, it's out of the question.

 

[R6 Racer]

First off I am NOT an electrician!
BUT this sounds like a problem waiting to happen.
No matter weather you put a "box" at the end or not you still only have 30 amps.
A 20amp 110 & a 30amp 220 is 50 amps your trying to run threw a 30 amp circuit.
IMHO I think that set up with that kind of distance (distance in electrical = resistance) would be ok for your 20amp 110 service but no more.

Steve

Good luck with trying to sort things out...

 

[z28snksknr]

I just made a 10/3 extension cord - 25' long (garage is 22' wide). I didn't use the orange wire though: i found a rubber insulated 10/3 wire that was stranded (vs. solid copper). It looks and feels just like an extension cord, only larger. Cost me $75 including plug ends ($15 each). I suggest you go to Lowes / HD and get a length cut for you.

 

[Stretch660]

Can you install the compressor in/or just outside the house and run the hose from the house to the garage? And then you only need a 110 120 ft extension cord which seems a little more doable, since running electric to the out building permenantly is not an option.

Just my .02

Good luck.

 

[countrytech]

First off I am NOT an electrician!
BUT this sounds like a problem waiting to happen.
No matter weather you put a "box" at the end or not you still only have 30 amps.
A 20amp 110 & a 30amp 220 is 50 amps your trying to run threw a 30 amp circuit.
IMHO I think that set up with that kind of distance (distance in electrical = resistance) would be ok for your 20amp 110 service but no more.

Steve

Good luck with trying to sort things out...

I know I will only have 30 amps. I don't need anymore than that at a time, I just want the capability for a 30A 220v -OR- (2) 20A 110v

At any given time I would only be running a single saw or piece of equipment plus a couple lights, and nothing I have is rated over 15 A at this point. If I run the air compressor on 220 I would be using that at different times than the saws, so they would not run concurrently.

I just made a 10/3 extension cord - 25' long (garage is 22' wide). I didn't use the orange wire though: i found a rubber insulated 10/3 wire that was stranded (vs. solid copper). It looks and feels just like an extension cord, only larger. Cost me $75 including plug ends ($15 each). I suggest you go to Lowes / HD and get a length cut for you.

I already have (from a previous project) 120ft of 10-3 but it's solid, and doesn't bend very nice... is your extension cord simply a 220v cable or did you break it down to 2 110v?

Can you install the compressor in/or just outside the house and run the hose from the house to the garage? And then you only need a 110 120 ft extension cord which seems a little more doable, since running electric to the out building permenantly is not an option.

Just my .02

Good luck.

I might have to look at that idea... (wonders how excited the wife will be about noisy air compressor next to family room).... it would solve the 220v to shop issue, but then I'd need to get a 100' air hose to wrap up every time i want to work in my shop.


A couple kickers with this whole deal is that we may eventually hardwire electric into the shop, but that is up to the whim of the landowner, and whether he wants to deal with permitting and inspections.... Money is too tight for me to just do it because it's not my property and it will cost several hundred bucks till I get a breaker panel, more wire, conduit, trencher, permit, ect. We have to cross my driveway to get anything between the house and the shop.

The other issue is my degenerative neuropathy that causes a lot of MS like symptoms and so walking back and forth and dragging and unwrapping multiple cables/hoses to and from my shop gets to be a serious p.i.t.a. It's all doable, but till I get everything setup I'm half tired, and then when I am done with whatever project I have, or too tired to keep going, wrapping up hoses and cables again is almost out of the question....

 

[johno]

Why not run the 10/3 to a small panel and then thru properly sized breakers for each outlet. That way you wont have a 20A outlet on a 30A breaker.
This sort of thing is done on temp. const. site panels often.

 

[wssix99]

As said above, your distance is too long, the wire needs to have outdoor insulation, the wire needs to be stranded, and the wire needs to be a larger gauge. If you are planning to leave the wire outside, you really need to cover all of the above to be safe on even a basic level. (UV light and solid wire won't hold up loose and outside.)

It is possible to get special-purpose extension cords in this size but they will run hundreds and hundreds of dollars.

There is also the lawn thing. I would not want to be the one who runs over a 220 30A cord with a lawn mower!


For your situation, I think your best bet would be to get a generator. It will give you power right where and when you need it. It's also portable so you can use it in other places (or a power outage at home!) and can resell it in the future. No extension cords to worry about.

 

[electrican]

wire your shop, just do it right!

 

[Aceman]

You need 10-4 SO cord. I'd buy a small main breaker panel and mount it to say a 2' x 3' piece of plywood. Mount the panel at the top and put some receps in 4 sq boxes with offset ******* into the bottom of the panel. When the time comes someday to run permanent power to your shop, etc you can simply pull this panel off the plywood and stick it in your wall.

Don't just tap off a 30 amp dryer recep for a 20 amp 120v recep though. That's definitely not the right way to go about it.

 

[Berserker]

As said over 100 feet, so either need to limit it to 20 amps, or go with bigger wire.

This can work, I have thought about it. If you want to go this route you should get some UF. Then when the time comes, you can bury, just leave a bunch of slack in it.

One thing to make this safer would be to simply turn it off at the source when not service.

Using the romex isn't a good idea, unless you just plan on doing it a few times with an eye on it.

I would keep dogs away from this.

One thing you could do,if you really, really didn't want to rent a trencher, would be to lay out a 100' run of PVC. Don't bother glueing it just snap to together. This would protect it from physical injury and protect people.

For me my barn is 8' away, but its 8' of concrete with my service running under it. I was thinking of rolling out a cable when I need it.

 

[ddawg16]

You need 10-4 SO cord. I'd buy a small main breaker panel and mount it to say a 2' x 3' piece of plywood. Mount the panel at the top and put some receps in 4 sq boxes with offset ******* into the bottom of the panel. When the time comes someday to run permanent power to your shop, etc you can simply pull this panel off the plywood and stick it in your wall.

Don't just tap off a 30 amp dryer recep for a 20 amp 120v recep though. That's definitely not the right way to go about it.

Key word....SO Cord....that is the stranded wire with a good rubber outer layer....made for flexible use. As noted by many others above, 10-3 wire is solid core and will break in no time with any kind of flexing.

 

[Norcal]

NM cable's jacket is not suitable for use as a cord + solid conductors are not either, do the job right & use the correct materials.

 

[z28snksknr]

Went out and snapped some pics:

Wire info - 10/3:

Plug End:

Receptacle End (temporary - i'm putting this in a junction box that will be fixed on my welding table, once I use the welder to build it that is):

Shot of the stranded wire:

 

[GirlnAgarage]

Nice pics. Similar to what I'm running ^^^, well, a 12/3 on a 35' run and a 30A outlet on the dryer. Works fine and only used when the stick welder is needed. Probably should have jumped up to the 10/3 but for the 30A I'm tripping the breaker anyway (it only happened once!)


I also got the wire cut and found the plug/receptacles from HD.


Another option is the long RV cords. Sometimes those are on sale. Just get the ends you need.

 

[Berserker]

Nice pics. Similar to what I'm running ^^^, well, a 12/3 on a 35' run and a 30A outlet on the dryer. Works fine and only used when the stick welder is needed. Probably should have jumped up to the 10/3 but for the 30A I'm tripping the breaker anyway (it only happened once!)


I also got the wire cut and found the plug/receptacles from HD.


Another option is the long RV cords. Sometimes those are on sale. Just get the ends you need.

Is the breaker 20 amp? 12 ga is good for only 20 amps. If you got a 30 amp breaker that is bad. 30 outlet is ok, as long as breaker is 20 amps.

 

[Berserker]

I am not worried about the solid wire so much as outdoor rating. UF would work, if just leaving it laid out.

But it should have some physical protection, PVC conduit laid on the ground would work great. Even some black plastic drainage pipe, that comes in the rolls, would work.

 

[GirlnAgarage]

Is the breaker 20 amp? 12 ga is good for only 20 amps. If you got a 30 amp breaker that is bad. 30 outlet is ok, as long as breaker is 20 amps.

You made me look again. I am running a 10/3 cord. My mind is slippin' already??

 

[abnorm]

Z28............

You are mixing two different (voltage) cord ends on the same cord (NEMA 5-50 for 120 volts and NEMA 6-50 for 240 volts)

You're wiring 4 wire cord to a three wire receptacle.......You can NOT put two wires (black and red) in the same hole/screw ......

What are you attempting ?

May this link will help

http://www.stayonline.com/reference-nema-straight-blade.aspx

 

[Berserker]

Run a 3 conductor. 2 hots, and nuetral. Put in 4 circuit panel in the shop. This will give you two 120 circuts and one 240 circuit. Put the 15 or 20 amp breakers on the 120 circuits.

If you want 30 amps 220 in the shop run #8 copper, since over 100 feet, and put a 30 amp breaker at your main panel.

 

[Norcal]

Run a 3 conductor. 2 hots, and nuetral. Put in 4 circuit panel in the shop. This will give you two 120 circuts and one 240 circuit. Put the 15 or 20 amp breakers on the 120 circuits.

If you want 30 amps 220 in the shop run #8 copper, since over 100 feet, and put a 30 amp breaker at your main panel.

This is absolutly horrible advice. A 4-wire feed is required.

 

[Berserker]

What are you talking about?? 2 hots and neutral, is what you have in the panel in your home. The ground is not counterd as a conductor.

Think about it 10-3, has four wires in it. If you don't know this, you really should be giving any advice. If you do, you shouldn't be confident.

Guy runs 3 conductor out there. Puts in 4 circuit panel. 2 pole 240 breaker, and two single pole breakers.

 

[ibedayank]

The OP has to string out the cord then when done he has to roll it up. Not just leave it in place that is the problem here.

 

[mrb]

What are you talking about?? 2 hots and neutral, is what you have in the panel in your home. The ground is not counterd as a conductor.

Think about it 10-3, has four wires in it. If you don't know this, you really should be giving any advice. If you do, you shouldn't be confident.

Guy runs 3 conductor out there. Puts in 4 circuit panel. 2 pole 240 breaker, and two single pole breakers.

Unlike romex, portable cord counts all the wires. 10/4 has four conductors, black, white, green, red. 10/3 would have black, white, green.

Dont use romex or other solid wire in plugs made for portable cordage. The terminals are designed for finely stranded wire and can deform when used with solid wire resulting in a loose connection. Read the instructions for most plugs and they will say stranded wire only.

 

[GirlnAgarage]

Unlike romex, portable cord counts all the wires. 10/4 has four conductors, black, white, green, red. 10/3 would have black, white, green.

Dont use romex or other solid wire in plugs made for portable cordage. The terminals are designed for finely stranded wire and can deform when used with solid wire resulting in a loose connection. Read the instructions for most plugs and they will say stranded wire only.

That's what I'm running. I've also noticed the discrepancy when reading input from guys - some say 10/2, some say 10/3 to describe the same cord when I was doing the research for my application. Just looking for more confirmation on the appropriate way to describe it. I thought mrb's description ^^^ was the proper way. Confirm?

And running 3 or 4 wire depends on what you need to plug into. I'm plugging into a 10-30R.

Here is my 10-30P

 

[Norcal]

What are you talking about?? 2 hots and neutral, is what you have in the panel in your home. The ground is not counterd as a conductor.

Think about it 10-3, has four wires in it. If you don't know this, you really should be giving any advice. If you do, you shouldn't be confident.

Guy runs 3 conductor out there. Puts in 4 circuit panel. 2 pole 240 breaker, and two single pole breakers.

Your the one who needs to heed your own advice. 10/3 flexible cord has 3 conductors,4 are required.

 

[Aceman]

To help clear up the confusion, if you have a 3 wire dryer recep(2 hots, neutral) you can't run a portable subpanel off of it. You need a 4 wire recep(2 hots, neutral, equipment grd).

What are you talking about?? 2 hots and neutral, is what you have in the panel in your home. The ground is not counterd as a conductor.

Think about it 10-3, has four wires in it. If you don't know this, you really should be giving any advice. If you do, you shouldn't be confident.
Guy runs 3 conductor out there. Puts in 4 circuit panel. 2 pole 240 breaker, and two single pole breakers.

You know Norcal is an electrician, right?

 

[Berserker]

I thought we were talking about romex still. I was an electrican too. Then did consulting, code, that was 10 years ago though. Now I build and checkout substations. Electrical Engineer, PE.

He may be an electrian but using the term horrible advice is over kill. There was a communication break down.

I repeatedly said 2 hots and neutral, if you don't know to pull a ground, then you shouldn't be wiring. The w wire plugs you see are straight 240 or old dryers that didn't use the neutral, they ran the timer off the ground.


I also agree solid is a bad idea if he rolls it up. Thats why I said put it in something and leave it on the ground. Leave enough slack in it, so when he trenches he can just drop it in the hole. This depends on the location. He doesn't want to leave a conduit above ground right on the patio.

Though either way he needs to buy new cable, 10 is to small for that long of run if he wants 30 amps.

 

[Norcal]

W/ a 3-wire cord/supply & 120/240V you have to ground to the neutral, this is why I wrote it it was horrible advice, since it is not kosher in the situation written about. (There is some crazy stuff on the internet).

 

[Berserker]

I meant 3 wire romex,10/2, which has its own ground. He was orginally talking about that.

I thought it obvious he would have neutral if he wants to have 120. But I guess nothing is obvious.

Dryers it probably doesn't hurt anything, but all your running is a timer.

 

[Norcal]

I meant 3 wire romex,10/2, which has its own ground. He was orginally talking about that.

I thought it obvious he would have neutral if he wants to have 120. But I guess nothing is obvious.

Dryers it probably doesn't hurt anything, but all your running is a timer.

It was allowed to ground the frames of ranges & dryers to the neutral, it is now prohibited except in existing installations done prior to the adoption of the 1996 NEC, a 10/2 NM cable to a dryer is and always was a code violation.
Dryers use 120 volt controls & the drive motor is 120V.

 

[electrican]

Went out and snapped some pics:

Wire info - 10/3:

Plug End:

Receptacle End (temporary - i'm putting this in a junction box that will be fixed on my welding table, once I use the welder to build it that is):

Shot of the stranded wire:

that looks real safe! wtf

 

[Berserker]

It was allowed to ground the frames of ranges & dryers to the neutral, it is now prohibited except in existing installations done prior to the adoption of the 1996 NEC, a 10/2 NM cable to a dryer is and always was a code violation.
Dryers use 120 volt controls & the drive motor is 120V.

Yes I know it is. But its been done a long time on dryers. Millions of homes have 3 wire dryers. Just pointing out a fact.

If you read my post, I said he would need a neutral if he wanted 120, since he is not installing a dryer in his tool shed.

 

[SgtRauksauff]

they make 10 ga. extension cords for RV stations.

 

[Berserker]

That would probably work, if not for the distance. Though in reality, wire is ran farther then 100 feet without being upsized. But if you are going to have to go out and buy something, might as well buy the right thing.

 

[countrytech]

where to go from here...