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Many different views here. I might as well get my feet wet. 12-2 wire is rated for 20 amps and 10-2 wire is rated for 30 amps. 12-2 and 10-2 wire has black and white insulated wires and a bare copper neutral wire This is not a neutral wire, it is a safety ground wire. the white wire is the neutral, black is hot. 12-3 and 10-3 have black red and white insulated wires and a bare copper neutral wire. again, bare is safety ground The saw you are looking at is rated for 14 amps. The questions you asked were

(If I'm only using the outlet for the saw, and nothing else, can I just run 10 or 12/2 for the 5' run of wire?

Is there a reason I'd need to run a 12/10-3?

Do I need to swap out the 50A breakers?)

So... It is ok to run 12-2 wire to the outlet. IF the saw only requires 240 vac, and not 120/240 vac, then yes, a two wire cable is adequate. There is no need to run 12-3. Replace the 50 amp breakers with a 20 amp double pole breaker.
... see in red
 

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Nine Thumbs
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Post #21 is exactly why you need to heed post #17 and #18. Very little information in #21 is correct. I hate to call people out, but using a grounding conductor as a neutral is not only against all code requirements, it can be downright dangerous. The neutral wire in a multi conductor cable is a CURRENT CARRYING CONDUCTOR. Thus the insulation around it. A ground wire is NOT insulated and therefore it cannot, and better not be used as a current carrying conductor.

That said, let me give you the correct information again: Electrical | DIY Home Improvement Forum (diychatroom.com) .

I am a 38 year licensed master electrician. I will not give you advice here. I (and my colleagues) will help you over there.
 

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Very little information in #21 is correct. I hate to call people out,
So who are you calling out as incorrect? The author of post #21 or the info from post#19?

Seems to me TimPA in #21 (his words are typed in red) is saying the same thing you are.
 

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Discussion Starter #24
Ok, well there’s a few too many quotes to reply to all but thanks for the input. #1 the house is mine, #2 if I complete the work, I have no intention of doing anything outside of code, not sure that I implied that? So, George, the inference “that’s not what a military member does” is a bit harsh considering I never implied it would be a jury-rig job- at least I hope I didn’t. #3 I have a contractor coming in to inspect the work if done by me. #4 I posted on this forum vs an electrical professional’s forum bc I quite often read great advice, correct or not, to get a general idea of the scope of work. As I said, I’ve already gotten a contractor for other work that will either inspect it or do the work so either way, it’ll be done correctly. I’ll def keep in mind the DIY forum.
 

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where's my table saw?
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What you said is correct, except you need to be careful about terminology. "12/3" in this case would refer to 12 gauge, 3 conductor wire plus ground (4 total), when you actually meant 2-conductor plus ground (3 total).

The reason this is confusing is because flexible cord (i.e. extension cord cable) is identified by the total number of wires--including ground, but Romex-type wire is identified by the number of "current carrying conductors "plus ground".

The OP needs to use 12/2 with a 2-pole, 20-amp breaker to install his outlet.
Yes, it's always been a bit confusing because of the ground (green wire) in the SJ type cords and the bare wires that wrap the conductors on a Romex cable. Then throw in whether or not the Neutral is "bonded" in the main panel. The Neutral is typically kept separate from the "ground' wires on the sub-panel. Then throw in a EMT conduit which is another conductor in itself and can become a ground for the receptacles.

This explains it rather simply in that the neutral is a current carrying conductor where the ground is not:
Probably a better explanation:

More info to read:


 

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That Guy
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I don't understand why people would tell him to go to the hardware store to buy 5 feet of 12-2 AND a 20 amp breaker when he can go to the hardware store and buy 5 feet of 6-2 wire for less and use the breaker that's there!

If he uses the breaker that's already installed he doesn't have to cut the power, remove the meter or work on a live panel, he just flips the 50A OFF, removes the two existing wires, inserts his two new ones, tighten the screws and flip the breaker back on.

To me this looks so much simpler and cheaper and arguably safer, than swapping out a breaker.

Am I missing something?
 

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I don't understand why people would tell him to go to the hardware store to buy 5 feet of 12-2 AND a 20 amp breaker when he can go to the hardware store and buy 5 feet of 6-2 wire for less and use the breaker that's there!

If he uses the breaker that's already installed he doesn't have to cut the power, remove the meter or work on a live panel, he just flips the 50A OFF, removes the two existing wires, inserts his two new ones, tighten the screws and flip the breaker back on.

To me this looks so much simpler and cheaper and arguably safer, than swapping out a breaker.

Am I missing something?
Well, i wont outright say that your assessment is wrong, but personally i wouldnt do it that way for a few reasons. First reason, the outlet, or rather the plug on the saw and the outlet it requires. If the saw is only rated for 15 amps, so im guessing the plug is either an NEMA 6-15 or 6-20. Putting the matching outlet on an existing 50 amp circuit would be an electrical code violation, since both those outlets are rated way, way under the 50 amps the breaker is capable of delivering, so the only way to make it work would be to swap the cord on the saw, which would mean a new cable, properly sized, with the correct plug to match the 50 amp outlet. Adds a fair bit to the cost.

Other reason, for me, would be safety. If something happens, maybe you have a short in the motor, maybe something stalls, whatever, a breaker that trips at 20 amps will trip a lot sooner than one that trips at 50 amps. Unless you need the capacity, better to go lower in my opinion, otherwise itd be like watering your lawn with a firehose

When it comes to electricity, theres an easy way and a proper way. Sometimes the easy way and the proper way are one and the same, but if they arent and the easy way is chosen over the proper way, bad things tend to happen.
 

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That Guy
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OK, that's what I was missing, I forgot about the "outlet".

In my mind he was wiring the saw right into a box, which also saves the cost of the outlet but sacrifices portability.
 

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Ancient Termite
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Guys, guys, guys!

The outlet box must be grounded. Some localities may permit the ground to go through metal conduit. It is best to ground the box with the ground wire in the Romex. If you are running in conduit it is best to use a green wire.

In North America, because we use the neutral type of wiring, the 230 Volt outlet must have neutral (White wire), per code, in addition to the two hot wires (red and black). So many of today's machines operating on 230 Volts use a magnetic power switch. If power drops, the magnetic feature of the switch requires the green button to be pressed again to start operation. Assuming 12 gauge, the appropriate designation for the wire is 12/3 with-Ground.

Yes, I know it is possible to operate a 230 Volt machine with only 2 wires. But it is not code and you shouldn't.
 

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Interested Observer
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Guys, guys, guys!

The outlet box must be grounded. Some localities may permit the ground to go through metal conduit. It is best to ground the box with the ground wire in the Romex. If you are running in conduit it is best to use a green wire.

In North America, because we use the neutral type of wiring, the 230 Volt outlet must have neutral (White wire), per code, in addition to the two hot wires (red and black). So many of today's machines operating on 230 Volts use a magnetic power switch. If power drops, the magnetic feature of the switch requires the green button to be pressed again to start operation. Assuming 12 gauge, the appropriate designation for the wire is 12/3 with-Ground.

Yes, I know it is possible to operate a 230 Volt machine with only 2 wires. But it is not code and you shouldn't.
Is the requirement to power a particular saw and switch to code different than the requirement to power a standard 20a receptical to code?
 

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If he was not confused before, the original poster must be totally confused now. This thread has wandered all over and has had much information contrary to other information.

At this point he needs to confer with the landlord and see what he/she wants done.

George
 

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Interested Observer
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If he was not confused before, the original poster must be totally confused now. This thread has wandered all over and has had much information contrary to other information.

At this point he needs to confer with the landlord and see what he/she wants done.

George
He is the landlord. The home is his.
 

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If he was not confused before, the original poster must be totally confused now. This thread has wandered all over and has had much information contrary to other information.
Yup. What is it about the topic of electrical work that causes so many people with zero knowledge on the actual topic to chime in? You don't see it happen with any other topic...just this one. And it's not just a case of some people having a minor misconception of the topic...it brings out people who are totally off the wall on the topic.
 

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I didn't think this topic was that complicated...

It just becomes that way..
 

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where's my table saw?
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I didn't think this topic was that complicated...
It just becomes that way..
It is far more complicated than meets the eye, as opposed to woodworking. Woodworkers are not licensed, but electricians are trained and licensed and they also offer degrees in electrical engineering, but not in woodworking so far as I know. Electriclity can kill you "dead" in a second, woodworking not so much, maybe a lost finger, or a bruised abdomen.
It's not complicated to those who know what they are doing, but can be to those who don't fully understand it along with all the CODES that determine whether wiring is safe. Woodworking doesn't need to abide by any codes, just good practices. So, a simple question can evolve into a long discussion with many opinions and only a few correct answers.
 

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Yup. What is it about the topic of electrical work that causes so many people with zero knowledge on the actual topic to chime in? You don't see it happen with any other topic...just this one. And it's not just a case of some people having a minor misconception of the topic...it brings out people who are totally off the wall on the topic.
You can't see electricity, just what it does. Hard to compare it to something else spatially, it isn't like water plumbing for example. When you throw in different phases, wire colors depending on the situation, the difference between ground and neutral, yikes.

A big issue, there are setups that will work, or seem to work, but are dangerous and might not cause a problem for a long time.

I've had success wiring work tables for 120v with switches and outlets, but I need to know a lot more to go beyond that, for some upcoming projects I'll ask over on the DIYChatroom for a good book to read. And then before I do anything with 220 or in the panel etc I will ask there, in detail.
 

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Ancient Termite
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I can go along with how bad it is.

Awhile back there was a magic wiring device for sale. The device could convert two 115 volt circuits into a single 230 Volt circuit. It was something like $90 plus shipping.

The device was a simple three headed cable. Two 115 plugs and one 230 socket. The only catch for it to work is one plug had to be plugged into the black side and the other into the red side from the main line. (I don't know what to call the sides of the line as it definitely isn't Phase.)

Thankfully the device is no longer on the market. Yes, I know that it "would" work but if you popped one of the breakers the remaining one would still be providing a lethally potent bit of electricity into the machine.

Hopefully nobody here is using the device.
 

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Hopefully nobody here is using the device.
I can neither confirm nor deny that i may or may not have created a device with a similar function. I can, however, confirm that its an unbelievably stupid way to get 220v power, and its a fantastic way to electrocute yourself, but it does technically work. That said, you shouldnt even think about doing it unless youre a very experienced electrician, but if youre an experienced electrician then you dont need that warning, and you also know that its smarter to just wire a new 220v outlet in
 
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