ExtensionCordGauge

Dec 12, 2003 29 Replies

I did google, but I'm still confused.



My table saw draws 15 amps. I have been using a 100 ft 16 gauge extension cord to run her, but I found out recently that this is to wimpy a cord. My manual recommends a 12 gauge extension cord not exceeding 50 feet.



My question is if I go to 100 feet of extension cord, is 12 gauge still ok? I guess do to the voltage drop with the longer cord that I may need a 10 gauge cord?


100 foot cord! You need a power cart with GPS to go from the workbench to the saw! :)

You don't need GPS, you just follow the bright orange cord! :)

On Fri, 12 Dec 2003 21:17:10 GMT, "stoutman" wrotg:

Here's some numbers for you:

16 ga is 0.4016 ohms per 100 ft. = 6.024 volt drop at 15 amps 12 ga is 0.1588 ohms per 100 ft = 2.38 volt drop at 15 amps

I'd say 12 ga is fine.

John, in Minnesota

The extension cord should say how many amps it can handle. If your 100ft 12 gauge says 15a is okay, you are fine. Since we don't know what the insulation is made of, we can't really say.

That is just what is safe. Whether it is reasonable is a whole other story. Unless the outlet is right next to the panel, 15a is a lot to put through a 100' extension cord; don't do it unless you have to as it is probably not good for your motor. Somebody pointed out the voltage drop was not too bad, but he ignored the voltage drop to the outlet.

Go to a 10 guage if over 50'.

As it is, you have a disaster waiting to happen.

I have a 100 ft power cord for my saw, it's 10 ga; however, it is also wired for 240V service.

If you ever try to rip 8/4 white oak, you will understand why.

For your application, if you decide to use 12 ga anyway, at least operate at

240V.

HTH

Mine's bright yellow.

Charlie Self

"In the final choice a soldier's pack is not so heavy as a prisoner's chains." Dwight D. Eisenhower

Mostly good stuff here, but 8 is not necessary. The advice to go to 240V is good. Why not staple a piece of Romex to the ceiling and be done with it. Portable cordage is very expensive!

12 will do fine at 120V, unless you are running max load or more. At 240V,

On Fri, 12 Dec 2003 15:38:45 -0600, John wrotg:

Dang, screwed up that one. You must figure 200ft because the 2 wires. I knew that. Yup, 12 is definitely out. 10 is on the edge. 8 would be the safest way to go, especially figuring the voltage drop to where you're plugging it into. Sorry for the mis-info.

John, in Minnesota

No ceiling to staple to. I'm running power to a workshop in the backyard. If I owned this place (I rent) I would run some conduit and permanent power out there. This is a temporary situation.

How about 50 feet of 12 gauge at 110 V ?

I don't know enough about electricity to know if this idea is any good, but I've wondered about building an extension cord that uses two identical sets of conductors. The male end could be two plugs. The female ends would connect to the proper locations on a standard dual outlet. Would this work?

-- Mark

Thanks to all who posted. I need to seriously reconsider my power situation.

Do they make a cordless table saw? Just kidding.... :)

And duh, use only one of the two outlets on the female end.

-- Mark

calculator requires #8.

2) 3% is a code requirement for branch circuits. It has nothing to do with extension cords. As I indicated above, 100' is probably not a good choice, but if the extension cord is rated for 15a, it is legal.

A gasoline generator with an 18 wheeler's muffler (to cut down the $#!!#%# noise) might be a solution.

-- Mark

My original calulations would be valid for 50ft.. I see Mark Hopkins link agrees. Very handy calculater by the way.

John, in Minnesota

On Sat, 13 Dec 2003 02:13:37 GMT, "stoutman" wrotg:

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