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Extension Cords-Which to Use First? #72654
12/06/06 03:57 PM
12/06/06 03:57 PM
wendel  Offline OP
Joined: Aug 2004
Posts: 55
I have two extension cords both are 50 feet long. One is 12 gauge and the other is 14 gauge. I want to power an electric saw.

I want the least voltage drop over the combined 100 feet so I keep the current draw by the saw motor as low as possible minimizing heat damage. Which should I plug into the 120 volt receptical first? Why?

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Re: Extension Cords-Which to Use First? #72655
12/06/06 04:16 PM
12/06/06 04:16 PM
scameron81  Offline
Joined: Feb 2004
Posts: 75
Healdsburg, ca, USA
I don't think it matters. The resistance will be the sum of the two extension cords regardless of which one comes first and the distance is still the same. But I could be wrong (it wouldn't be the first time.)

Re: Extension Cords-Which to Use First? #72656
12/06/06 04:53 PM
12/06/06 04:53 PM
SvenNYC  Offline
Joined: Aug 2002
Posts: 1,691
New York City's still, essentially two resistors in series. Don't think it really matters which "gets it" first.

If it makes you feel better, though, I'd go with the #12 first and then hook in the #14.

Of course I betcha the wiring in the wall is #14.... [Linked Image]

Would there really be THAT much voltage drop over that much wire?

Re: Extension Cords-Which to Use First? #72657
12/06/06 05:15 PM
12/06/06 05:15 PM
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
It's all going to be one series circuit whichever way you do it:

#1. Hot -> 50' #12 -> 50' #14 -> Tool -> 50' #14 -> 50' #12 -> Neutral.

#2. Hot -> 50' #14 -> 50' #12 -> Tool -> 50' #12 -> 50' #14 -> Neutral.

Either way you have 100 ft. of #14 plus 100 ft. of #12 conductor in the circuit, so the resistance of the extension cords will be the same.

Re: Extension Cords-Which to Use First? #72658
12/06/06 05:36 PM
12/06/06 05:36 PM
rabbitgun  Offline
Joined: Jul 2006
Posts: 23
Nope it does not matter.
That said, even with a 16A load the drop is only right around 4 volts.

Re: Extension Cords-Which to Use First? #72659
12/07/06 04:15 AM
12/07/06 04:15 AM
e57  Offline
Joined: May 2003
Posts: 2,876
Have you thought of installing an outlet closer? [Linked Image]

Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Extension Cords-Which to Use First? #72660
12/07/06 10:34 AM
12/07/06 10:34 AM
Zapped  Offline
Joined: Oct 2002
Posts: 482
Huntington Beach, CA, USA
Two resistors in series: R(total)=R1+R2. No difference with placement. If it's causing you to lose sleep, spend the $20 on another 50' #12 extension.

Re: Extension Cords-Which to Use First? #72661
12/08/06 07:56 PM
12/08/06 07:56 PM
napervillesoundtech  Offline
Joined: Feb 2006
Posts: 144
Naperville, IL, USA
Think about inrush current, though. Get a 100' 10/3 cord. just a thought.


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