Wiring for 220

[Herb Droogendyk Orkney ON]

Just picked up a used King table saw. I need to install a new 20 amp 220 volt breaker, which is doable. Lots of power in the box.

The saw will move around the shop and I don't want to install a number of 220's.

My question is: can I run an extension type cord suitable to carry the amps and volts right from the box? The shop is not big and 25' of cord will let me drag the saw around.

By the way, the saw was advertised here on the classifieds. They do work.

Just like we did' humping the saw with the shop made base and saw dust collector attached up a flight of stairs with a turn near the top. It was good that I was the only old guy there.

Thank you in advance for your advice.

[Allan Johanson - South Su]

By running an extension cord "from the box", you mean installing a proper 20A/240V receptacle in the wall near the breaker box, right? I hope so. :-)

If I were you I'd install the receptacle where it would make the most sense in my shop and then make a #10/3 extension cord (use the proper wire - not the "in-wall" stuff) with the 20A ends. It requires a bit of patience fitting that #10 wire into the ends, but it is doable. I made one for my welder.

Since you are so close to the breaker box #12 might be fine, but if you're like me you'll always over-engineer things. :-)

Have fun!

Allan

[J.P.Rap(Hamilton)]

Hi Herb
My basement is 30' end to end.The shop is at one end and the breaker box is at the other end.
I ran 220V 12/3 from the breaker box to the beam in the center of the shop.I installed two 110 V and one 220 V outlets in that location.
The coard on my saw is 12 FT of 12/3 braded wire. I can run the saw from anywere in the shop area.
If you were to do the same , I think you'll have no problems.
Remember, you draw half the amps on 220 V than you do on 110 V.

FWIW
J.P.

[Rajiv_in_KW]

You mean you split one 220v run to give you two 110v outlets & one 220v? can you do that? If it's doable then that may save me some headaches

--Rajiv

[Mike on the Wet Coast]

I agree with Al, either 12/3 or 10/3. Ask the hardware store for extension cord wire.

[Mike Harris, London]

Hi Rajiv

No, that's not correct. What J.P. is saying is as the voltage increases the current decreases. You may have taken pyshics in grade 11, current is inversely proportional to the voltage.

For example Herb didn't say what kind of saw he bought but I suspect it's a contractor saw. So on 120V it probably draws about 15A and on 240V about 9A.

Here it goes I'm going to open a can of worm's, some will say that motors run better on 240V than on 120V. It's not true they run exactly the same, they produce same amount of heat(P=ExI), there are a couple other things but there not worth mentioning. The only difference when you convert to 240V is, it allows you to run a smaller gauge of wire because the current is lower. But you have to install a 2-pole breaker.

Herb would need a 20A single pole breaker on 120V or a 15A 2-pole on 240V.

Mike

[Rajiv_in_KW]

Quoting J.P. ...
"I ran 220V 12/3 from the breaker box to the beam in the center of the shop.I installed two 110 V and one 220 V outlets in that location"

Which is why I asked. from reading that sentence it looked like he ran one circuit of 220v to his shop & then split it into two 110v & kept one outlet on 220v. offcourse, last time I read that post I was half asleep & right now I am only half awake. so..... :)

--Rajiv

[Tony Augruso]

Yes it is doable. However, I would suggest you run 220V from the box to an outlet and then plug the extension cord for the saw into that. That way if you ever get a second tool that requires 220V and you don't want to run another line you can just plug it in.

Tony

[Tony Augruso]

You can do that. Note that the wire he ran was 12/3 (which is really 4 wires if you include the ground wire). 2 of those wires would be hot carrying 110V each(totally 220V) the other would be the neutral wire(required for a 110V circuit). Depending on which wires you hook up to the outlet you can get 220V or 110V out of the same "wire". What you've done is run enough wires out to make up whatever combination you need.

Tony

[Mike Harris, London]

Hi Rajiv

I must have been half asleep as well. Tony's right but you'd have to consider your potential load and the #12/3 has to be connected to a 2-pole breaker.

Mike

[Rajiv_in_KW]

Cool. Thanks guys. my builder has left an open run of 12/3 in the basement. and I have been agonizing over trying to figure out whether I want 110v circuits in there or 220v. looks like I can have best of both world so long as I am careful.

--Rajiv

[Randy in Dartmouth]

Home Depot, type SOW "tuff as nails" cord. This is designed as equipment cords, is very flexible, and can handle being dragged around the shop floor. Put a twist lock plug and receptacle on the end, also available at HD.

I ran 3 conductor cable to my saw, and use the line-neutral wire to supply 120 volts for my router, which is mounted in the extension wing.

Cheers

Randy

[Ed/Leaside]

You can have the best of both worlds but it probably wouldn't pass code. I have three separate runs in EMT, one @15 A and two @20 A. Each run is 220 w/neutral and has two duplex outlets. Both duplexes are split (link tab removed) and the first has red to the top and black to the bottom, second has black to the top and red to the bottom. [Why would I do this? :)] It would be very easy to change one outlet to 220, but I'd have to pin-link the two breakers so they'd trip together as per code. At that point I don't think the 110/110 duplex on the same circuit would pass, although it would be functional. An electrician could answer that one.

[J.P.Rap(Hamilton)]

Thats what I did. I split the outlets and ran one hot wire to each and the neutral to both. I then wired a 6" cord from both hot lines out the side of the box and put a 220 V plug on the end of it.
I don't know if it is within code or not but it works and it is safe.
The only concern is if Im ever working on the line I have to ensure I switch off both breakers as they are not linked.
J.P.

[Ed/Leaside]

J.P., Is there any reason for not linking the breakers? Ed

[J.P.Rap(Hamilton)]

Yes...
I didn't think of it.
And now that its done, I can't be bothered.
J.P.