# Extension cord



## Aukai (Jan 6, 2018)

Where I wish to use my PM 1228 I'm about 12' short from the power outlet. What gauge of wire do I need to do a 15-20' extension cord for 110v 20 amps? thank you.


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## BGHansen (Jan 6, 2018)

Not an electrician, but house wiring is 14 gauge for 15 amps, 12 gauge for 20 amps and 10 gauge for 30 amps.  Looks like a 12 gauge should work fine for you.

Bruce


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## ttabbal (Jan 6, 2018)

I would use 12, but 14 is probably fine for a 20ft cord. I suspect the current draw will often be well below 20A.


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## Aukai (Jan 6, 2018)

Thank you gentlemen.


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## 4GSR (Jan 6, 2018)

Stick with 12 GA.  Technically by, NEC rules, 12 ga. SO, SEEW, type of cord is only good for 15 amps for 12 ga. and 25 amps for 10 Ga..  But that's based on full continuous loads. You should be good with 12 ga. for intermitting loads. Always make it a rule of safety, to unplug the cord when not in use.  Ken


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## Aukai (Jan 6, 2018)

4gsr said:


> Stick with 12 GA.  Technically by, NEC rules, 12 ga. SO, SEEW, type of cord is only good for 15 amps for 12 ga. and 25 amps for 10 Ga..  But that's based on full continuous loads. You should be good with 12 ga. for intermitting loads. Always make it a rule of safety, to unplug the cord when not in use.  Ken


Thank you, good to know.


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## jim18655 (Jan 7, 2018)

The problem with extension cords is the connections. Make sure the receptacle is tight and the female end on the cord is tight.

Table 400.5(A)(1) 25/20 amps for 12 AWG cords dependent upon 2 or 3 current carrying conductors,respectively.


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## 4GSR (Jan 7, 2018)

jim18655 said:


> The problem with extension cords is the connections. Make sure the receptacle is tight and the female end on the cord is tight.
> 
> Table 400.5(A)(1) 25/20 amps for 12 AWG cords dependent upon 2 or 3 current carrying conductors,respectively.


I generally go one size up on gauge verse amps from standard for extension cords to be extra safe. I've seen a cord or two that were hot from running to the max on amperage.  This was on 460v 3-ph, too.  Way too uncomfortable for me!  Like I said, better safe than sorry.

And I agree 110% on connections.  Don't skimp on using good quality connectors.  Use the one's that you insert the wire under a flat rectangular washer and secure with a good heavy screw.  Make sure the wires are secured and trapped under and sides by the terminal. 
The cord connectors you get cheap at Harbor Freight are not good enough in my shop.  Also the blades of the connector must hold tight with the plug with little movement.


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## higgite (Jan 7, 2018)

I suggest getting a UL listed cord that is rated for at least the same amperage as the circuit breaker that feeds the outlet that you will be plugging it into. An extension cord’s rating is based on more than wire size alone. ymmv

Tom


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## Aukai (Jan 7, 2018)

All good suggestions thank you. I do have experience with loose plugs.  I have spent some time up grading my garage from ONE, and only 1, 2 plug receptacle. EVERYTHING was on extension cords, which is where I was rolling on the ground to drain the compressor tank, it kicked on, my leg was on the plug in, and it arced real bad before the GFI tripped.

So now I have the original outlet, plus 4 quad outlets, 3 x 4 bulb florescent, 3 x 2 bulb florescents, and 2 x 220 50 amp, and 1 220 100 amp plug ins. With new breaker boxes.


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## Bill Gruby (Jan 8, 2018)

Why not just replace the machines power cord to a longer one. Simple solution.

 "Billy G"


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## projectnut (Jan 8, 2018)

areA b





Aukai said:


> Where I wish to use my PM 1228 I'm about 12' short from the power outlet. What gauge of wire do I need to do a 15-20' extension cord for 110v 20 amps? thank you.



Does your machine require a full 20 amps, or are you just using a 20 amp circuit?  Breaker should only carry 80% of it's rated capacity as a continuous load.  If your machine is actually drawing a full 20 amps it should be on a 30 amp circuit.

I did as Bill Gruby suggests.  Rather than run extension cords all over the shop I put longer cords on the machines.  In cases where it was feasible I rewired the machines for 220V and put in dedicated circuits.  All the machine outlets (110 and 220) in the ceiling so there are no cords running across the floor.  It makes it a lot easier to move materials through the shop when you don't have to navigate through an obstacle course of power cords.  Also with dedicated circuits the lights don't go out if you happen to trip a breaker.


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## Billh50 (Jan 8, 2018)

I always make a longer cord for the machine if needed. Also I always go with the larger wire just to be safe.


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## FOMOGO (Jan 8, 2018)

Ceiling drops are how I will be running mine as I have easy overhead access. You might consider running conduit from your new panel. It will cost less than your extension cord material and give you a better hard wired semi permanent connection, which you could run overhead, surface mounted too the ceiling above your lathe. As stated above, if your motor is convertible 110/220, it would be to your advantage to go 220V as it will draw considerably less amperage. Mike


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## ch2co (Jan 8, 2018)

No extension cords in my shop. When I first got my used lathe and minimill, I rewired the entire  little 12 x 16 ft. shop.  All lines are in 3/4" conduit. A A 40A 240V service goes into a sub panel with breakers. 120V lines run through wall mounted conduit with 4x4 boxes on roughly 4 - 6 foot centers with 4 electrical sockets in each around all 4 shop walls. The overhead lighting was left on the original inwall (ceiling) wiring.  The 220V lathe is hardwired into the 3 phase inverter then to the lathe. It is sooo nice to be able to just reach over and always have a socket to plug in whatever tool or accessory you are working with.  Its complete overkill and I love it. I've fought for the last 60 years of not being able to power up a tool / instrument 
without getting out an extension cord, and that has now come to an end, at least in the shop. The 3/4" conduit allows for easy wiring additions for
say a bigger mill. My shop is my electronics, woodworking and now metal working home and I bet that within the next year or so, I will have
used every outlet location.


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## Aukai (Jan 8, 2018)

I will look into making a longer cord, and possibly a drop. 20 amps is what the machine is supposed to be connected to, I'm assuming for max load. I have not seen any information about converting the motor to 220v. Thank you for all of the helpful ideas.


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