# Wire size for 240v shop tools



## secutanudu (Mar 15, 2009)

I am wondering what size wire i should run for my 240v outlets in the shop.the tablesaw and bandsaw I am getting both require 240v 15A circuits...should I just run 14/2? Any reason to go up to 12/2?

Is it ok to put multiple 240v outlets on the same circuit? I don't plan to use multiple 240v tools at once.

Thanks.


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## rrolleston (Oct 17, 2011)

Do you know if your tools will be needing a three or four wire receptacle?

I would use 250v 20a plugs with 12-3 or 12-2 and a 20a breaker


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## secutanudu (Mar 15, 2009)

3-wire I believe. (2 hots + g)


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## rrolleston (Oct 17, 2011)

accidental duplicate post


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## rrolleston (Oct 17, 2011)

If you don't plan on using any two at once one circuit would be fine. And 12-2 or 12-3 depending what your tools need.


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## secutanudu (Mar 15, 2009)

I had a bunchof 14/2 lying around I was hoping to use....any reason I can't use it? Req'd circuits are 15a.


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## junkcollector (Nov 25, 2007)

What are the actual nameplate amp ratings of the tools? (I'm just wondering if the tablesaw is [email protected])

Even if a 15 A circuit is all that is required, you may want to go with a 20 A circuit and receptacles because the NEMA 6-20 receptacles seem to be easier to find at big box stores and such. Depending on the amperage rating of the tools, you may be able to run say a dust collector and table saw from one 20 A circuit. Nothing wrong with 15A though. And yes, you can put as many as you want on one circuit. 

They also make duplex 240 receptacles or half 120 half 240 but you'll need to go to a supply house for them.


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## rrolleston (Oct 17, 2011)

Could try 14-2 with a 15a breaker and see what happens but sometimes a 15amp shop tool could draw enough when it gets worked hard to trip a 15amp breaker. I would try one outlet really close to the box and see how it goes. Work the tool how you think you will use it and if it works wire it up.


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## secutanudu (Mar 15, 2009)

I usually get all my electrical stuff from a supply house. I go enough that they gave me a contractor's account 

I don't have either the bandsaw or the tablesaw yet, gettin them in the next 2 weeks.

It lists the minimum circuit size, but what about the max? I'd love to be able to run dust collection on the same circuit, not sure ven a 20A could handle that. Looks like I'll be buying some more 12/2 (or 12/3).

Here's the info from the spec sheets:

Grizzly G1073 Bandsaw:
http://cdn0.grizzly.com/specsheets/g1073_ds.pdf
Electrical:
Minimum Circuit Size............................................................................................ 30 amps at 110V, 15 amps at 220V
Switch......................................................................................................................... On/Off Toggle with Safety Lock
Switch Voltage.............................................................................................................................................. 110/220V
Cord Length............................................................................................................................................................ 5 ft.
Cord Gauge................................................................................................................................................... 14 gauge
Plug Included........................................................................................................................................................... No
Motors:
Main
Type.................................................................................................................. TEFC Capacitor Start Induction
Horsepower................................................................................................................................................ 2 HP
Voltage................................................................................................................................................ 110/220V
Prewired..................................................................................................................................................... 220V
Phase....................................................................................................................................................... Single
Amps....................................................................................................................................................... 28/14A



Sawstop Cabinet Saw (3hp):
http://www.sawstop.com/products/professional-cabinet-saw/specs/
*Motor:* 
3 hp, 1 phase, 230 V, 13 A


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## rrolleston (Oct 17, 2011)

I would run dust collection on a separate circuit.


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## secutanudu (Mar 15, 2009)

The dust collector I am looking at is 120v anyway, just a cheapo 2hp from harbor freight.


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## rrolleston (Oct 17, 2011)

I would try 15 amp circuit and 14-2 or 14-3 wire and see what happens. I would not do any wiring until I knew for sure what they plugs are.


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## secutanudu (Mar 15, 2009)

They all use 3-wire, no neutral. just checked. The bandsaw doesnt ship with a plug at all, you wire it yourslef. I'm buying it used, no idea what it has on it. The table saw comes with a 3-wire 15A plug. 

So i'd definitely have to change the plug to a 20A, and possibly the bandsaw also.


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## secutanudu (Mar 15, 2009)

i guess i can run 12/2....on a 15A circuit with 15A plugs. That way if i do trip breakers, I just need to swap the outlets and breakers. If they don't trip, i dont need to do anything else.


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## rrolleston (Oct 17, 2011)

Why would you change the plugs?


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## secutanudu (Mar 15, 2009)

Well if I run a 20A circuit, can i put a 15A plug on that circuit?


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## rrolleston (Oct 17, 2011)

Yes the same thing as you do in your home plugging in tv's and vacuum. I would only change the cold if there is something wrong with it.


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## rrolleston (Oct 17, 2011)

Just make sure all connections are very tight and no corrosion at any of the connections.


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## secutanudu (Mar 15, 2009)

I'm just wondering if code allows use of a 15A outlet on a 20A circuit.

I know you can on a 15A 120v circuit if you have multiple outlets. not sure if the same rule applies for 240.


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## rrolleston (Oct 17, 2011)

I would use 20 amp outlets


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## junkcollector (Nov 25, 2007)

20 A receptacles can accept 15 or 20 A plugs. Perfectly OK.


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## secutanudu (Mar 15, 2009)

Great. And I can use them on a 15A 240V circuit?


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## 47_47 (Sep 11, 2007)

I'd run 12/2 on a 20 amp ckt. You may re-wire your dust collector to run on 240V and the 20 amp will handle a saw and the dust collector.

Andrew, are you getting the 36" or 52" fence? I have the 36" on my 3 hp industrial sawstop and its very good.


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## secutanudu (Mar 15, 2009)

yeah, I'll just go with 12/2. The 14/2 can sit around for a while longer.

I'm going with the 36" also. Going with the professional, not the industrial. I can't wait.


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## secutanudu (Mar 15, 2009)

I just bought a 240v blower. I plan to make an air filter for my shop and run it at the same time as my BS or TS. Can I put all 3 items on one 20A 240v circuit?

TS is 13Amps
BS is 15Amps
Blower is 2.8Amps.

So, at most, 17.8 amps out of 20.

This allowed, or does the blower need its own circuit?

Thanks.


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## Missouri Bound (Apr 9, 2011)

If you are planning on using 14 gauge wire, you can use no more than a 15 amp breaker. If you run 12 gauge wire you can use a 20 amp breaker. That's really all you need to know.


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## Missouri Bound (Apr 9, 2011)

secutanudu said:


> I usually get all my electrical stuff from a supply house. I go enough that they gave me a contractor's account
> 
> http://


 
Amazing....you buy enough there to have a contractors account but you don't know how to wire a simple circuit?:laughing:


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## curiousB (Jan 16, 2012)

junkcollector said:


> 20 A receptacles can accept 15 or 20 A plugs. Perfectly OK.


 
I recommend you use this style plug Nema 6-20 (because Nema 6-15 is harder to find). That means you *must* wire it with a 20A breaker and 12AWG wire. You can't put a 20A style outlet on a 15A branch circuit per code.

Run the 12-2 and have a little more upside for heavy tools.


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## secutanudu (Mar 15, 2009)

curiousB said:


> I recommend you use this style plug Nema 6-20 (because Nema 6-15 is harder to find). That means you *must* wire it with a 20A breaker and 12AWG wire. You can't put a 20A style outlet on a 15A branch circuit per code.
> 
> Run the 12-2 and have a little more upside for heavy tools.


That's exactly what I did (Nema 6-20, 12AWG, 20A breaker). I am just wondering if I should separate the blower onto its own circuit, since using both that and the bandsaw at the same time would put me at about 90% circuit capacity.


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## secutanudu (Mar 15, 2009)

Missouri Bound said:


> Amazing....you buy enough there to have a contractors account but you don't know how to wire a simple circuit?:laughing:



I know how to wire a circuit. My questions were not regarding how to wire it or what wire size is allowed on what size breaker, that part is obvious.

I am looking for practical recommendations to avoid breaker trips as well as safety/code issues I might not be aware of with 240v circuits, since this is the first time I am dealing with 240v with multiple devices attached to it.

Thanks for the comment, though.


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## curiousB (Jan 16, 2012)

secutanudu said:


> That's exactly what I did (Nema 6-20, 12AWG, 20A breaker). I am just wondering if I should separate the blower onto its own circuit, since using both that and the bandsaw at the same time would put me at about 90% circuit capacity.


 
I would live with it a while and see how it goes. Since the blower will be running before you start cutting its power on surge current will have passed before you cut anything. 5kW is a 6.7 HP. I doubt load will exceed that (unless your blades are dull and you're cutting African Ironwood). :laughing:


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## secutanudu (Mar 15, 2009)

I guess I'll give it a shot and rewire if necessary.

Well the blower is only 2.8 amps..

Where did you get the 5kW number?


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## curiousB (Jan 16, 2012)

secutanudu said:


> I guess I'll give it a shot and rewire if necessary.
> 
> Well the blower is only 2.8 amps..
> 
> Where did you get the 5kW number?


 
240 * 20 = 4800 watts rounded to 5kW. 

1 watt = 0.00134102209 hp


Motors are inductive so they have an inductive power factor but I didn't want to open up that can of worms.


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