shocking table saw

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I have an old Craftsman table saw that has an external motor. It runs the blade via two belts. it only has a 2 wire non-polarized plug. If I remember right its circa 1942. Anyway, frequently when we lean against it with a sensitive part of the body, ( face, belly, leg ) we'll get a slight zap. Can a ground wire be added to this to stop it? Where would one place it?
signature Troy & Michelle Hall Cogy Farm Clay Center, Kansas 67432
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Adding a ground would be illegal and dangerous. A ground is to protect you when you don't know there is a problem, not to let you use a defective tool. Don't do it. (It won't work anyhow if the short is from the hot; it would just trip the breaker.)
The short answer, combined with your question about the fence below, is to toss the saw; it just isn't worth it.
However, 1) Does the shock come when the saw is on or off? 2) Does reversing the plug change anything.
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I think its only when it is on and not always. It is VERY mild. Not a 110 shock. Which is whats weird. Not that I have noticed, but I haven't paid close attention to it. "Tossing" the saw is not at option at this time. I don't have $300+ to purchase a new one. This is a very sturdy tablesaw with a 9" blade.
signature Troy & Michelle Hall Cogy Farm Clay Center, Kansas 67432

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How do you know what a 110 shock should be like? It's the current that governs the 'mildness' of the shock, not the voltage.
Two possiblities:
1) The neutral conductor is wired to the frame of the saw (unlikely, but possible). Reversing the plug will give you a much larger shock if this is so (dangerous!)
2) Somewhere on the saw is an unintentional path to the frame from either the grounded or current-carrying conductor.
Unless you find the problem and resolve it, the saw shouldn't be used.
scott
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Nonsense, twice.
Electrical code applies only to premises wiring, not to cord-and-plug connected devices, so there's clearly nothing illegal about it.
And it obviously is less dangerous to properly ground the frame of the equipment than to leave it ungrounded.

Nonsense, a third time.
Chances are that there is nothing wrong with the tool. Did you notice the part where he said it's an unpolarized 2-prong plug? And if the tool *is* defective, adding a ground will *prevent* him from using it. Had you noticed that he *is* able to use it now???

Nonsense, times 4.
If the short is from the hot, he now has a table saw with an energized, ungrounded frame. If he adds a ground to it (e.g. by replacing the 2-conductor power cord with a properly grounded 3-conductor cord), _of_course_ it will trip the breaker -- which is obviously exactly the desired behavior if the hot is indeed shorted to the frame. In what sense is this "not working"?

Nonsense x 5...

Perhaps you should have ascertained the answers to those questions _before_ posting all that tripe.
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Illegal? Since when? I agree that it is appropriate to find the problem but since when is it illegal to add a ground to a device?

That is just plane bad advice.
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than to the neutral. If the machine had been made that way, it would be simply unsafe rather than illegal.

I can't comment on that, but it is plain good advice. Bear in mind he also said his fence was unusable. How much money do you want to put into a 62 year old 9.5" table saw?

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Utter nonsense. What on earth do you think an equipment ground is *for*, anyway?

So you think that *adding* an equipment ground to it makes it *less* safe than it is now?!
Amazing.
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Whaaaaat?
In all this discussion of ground & neutral, may I comment that, at least here in USA, most places the code calls for the ground & neutral to be bonded together @ the building load center or entry panel?
Considering the age of this saw, I would hazard a guess that the power cord & plug are not original, and who knows what kind of a botch job was done by whoever replaced/wired it?
I believe the best idea is to do as someone else suggested; buy a new 25' extension cord, but in 14ga. not 16, and rewire. Chances are the on/off switch only switches one side of the circuit, in which case you wire the *hot*, or black wire to the switch, the *neutral*, or white wire to the unswitched side, and the green to the frame. Now, if it pops the CB when you turn it on or plug it in, take the motor out & have it checked.
The amount of money the OP wishes to spend is purely up to him, given how useable the saw is if fixed.
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don't really care.
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That doesn't mean that it is acceptable for the grounding conductor (that you are calling 'ground') to carry _any_ current at _any_ time other than a fault situation that trips a breaker.
The GROUND _MUST_ _NEVER_ _EVER_ _EVER_ carry current!!!
(because it is tied to the metal frame of most appliances and to the conduit, your water pipes, and so forth und so weiter).
scott
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wrote in message

Oh Bullshit! If the grounding conductor was to never carry any current, it could not in any way protect the user. Those of us who have advocated a grounded system have also advocated repairing the original problem in association with installing a grounded solution. If he had the ground he'd likely not experience the current flow he's experiencing now. The breaker would trip and he'd know to fix the problem with far less risk of injury that with an ungrounded saw. It is quite possible in a grounded scheme for the leakage to be less than what will trip the breaker, so your opening comment is pure bull as is your all caps comment. The ground will carry current under a fault condition which serves to protect the user and that flow may or it may not trip the breaker. The fault condition must still be repaired, but no one is advocating anything different.
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I understand that Scott, and I apologize if I have not made that clear. I got a little carried away in response to the statement that the ground wire must never carry current. I do well understand that it is not to be wired for current but it seemed that there were people who were more interested in pointing out that it should not be wired to carry current than recognizing the fact that myself and others were only talking about this very sort of current carrying use - fault condition, very short duration.

I should have responded to one of your earlier posts which talked about neutral bonding of older motors and given recognition to the point that you made, but to be honest, by the time I saw it I really just wanted to bail out of this thread. The electrical threads always seem to get so hot - not that I don't owe my own responsibility to that. So... genuinely... thank you for pointing that out as it is indeed a factor that I had not considered. Damn - I had to learn something again today.
Thanks Scott - especially for being so patient while I suffered through my brain fart.
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No problem. I got a bit carried away with the emphasis, no doubt.

You're welcome.
scott
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Where did I say my fence was bad??????? It wouldn't work with a sheet of ply 6' x 36" deep. WELL DUH!!! the table is barely more then that!! I was making a cut 30" in from the end to cut the board into two pieces so I could laminate into a 1" top for a router table. Is my fence the easiest thing in the world to use... nope. Is it the most accurate? NOPE! Is it functional? YEP! Measure 3x cut once. PERSONALLY I can handle a 120v shock without much more then a blink. But I ain't gonna sit there and do it!! SHEESH. I realize it needs to be fixed. Thats why I asked the question in the first place! There has been a lot of useful information given on exactly how to do that and why I should NOT recitify the missing ground before doing these tests. Having a shop is a dangerous place. There are a million things that could go wrong and it is not wise to INTENTIONALLY bybass these safetys. HOWEVER, How many still have the blade guard on their saws? How many have a GOOD RF grade ground in their dust collection network? You do realise that is can instaneously combust don't you? Happens every day. How many have a FLASH proof rag container? Have a FLASH PROOF paint locker? Or even Flash proof ventilator? Lets stop the flaming and understand that we all probalby have things in our shop that we have/do that we shouldn't, and when it is obvisous to you that the OP doesn't realize that this may be dangerous, point out the reasons, and alternatives and then allow the OP to make the decision. It IS his/her life after all isn't it?
GOD BLESS and lets get back to woodworking

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On Tue, 14 Sep 2004 11:24:20 GMT, "Troy Hall"

You were doing fine until you got to that. Happens every day? Cite ONE verifiable instance where this has occured in a home workshop...ever.
- - LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
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Flame on!
wrote:

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Wiring isn't magic or voodoo, despite what some seem to imply. All it takes is a methodical approach and attention to detail. Most anyone who posts here should be able to look at a wiring job and decide whether or not it's within his or her comfort/ability zone. If you're wondering whether or not is IS, then it isn't. Simple.
1. Check the cord. Replace if necessary. See if it's feasible to add an equipment ground. If the motor neutral is isolated from the frame, you're good to go. If not, consider replacing the motor--old equipment that's neither doubly insulated nor grounded isn't worth the danger.
2. Cord okay? Take the motor to a motor shop.
3. Consider replacing the motor with a modern frame-grounded unit. If the saw is otherwise sound, it might be worth it.
4. If the saw is NOT otherwise sound, buy a new one.
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On Tue, 14 Sep 2004 16:10:26 GMT, "U-CDK_CHARLES\\Charles" <"Charles

No, US practice for wiring electric motors _is_ voodoo.
Europe is scared of your machinery wiring.
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