220v conversion question

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I just had an upgrade for my electric service to a 200 Amp panel as part of an HVAC upgrade. At the same time, I had the electrician put in 2 220 circuits and 2 120 circuits for my shop (lights were already separate). Last night I switched over my table saw to 220. Wow, start up is almost instant.
The question: I plan to switch over my bandsaw to 220 as well. What happens to the gooseneck lamp? The switch over instructions don't mention it. Rewiring for the motor is pretty straightfoward. Am I missing something?
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I wired the lamp with one hot line (110v) to the center, and connected a neutral to the outside. ( Sorry - I don't know the precise terminology.)
As an alternative, you can find 220v lamps on line.
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In most 240 circuits there is no neutral (certainly not those used for tools). Wiring it to ground isn't a good idea either.

A much better idea.
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snipped-for-privacy@gmail.com wrote: ...

Well, split-voltage appliances (ranges, dryers, ...) have run that way for approaching 100 years w/o any significant issues.
Only w/ a relatively late NEC revision did the requirement for 4-wire service come into play.
While it strictly speaking, isn't up to current Code, for a load no larger than the work lamp there's no issue imo.
This came up not too long ago and someone noted that between an early manual and later the particular manufacturer of his dp had dropped the illustration/wiring diagram for the split voltage, undoubtedly to maintain strict Code compliance from a liability standpoint. However, they hadn't changed the wiring iiuc... :)

Take your choice; I'd just rewire it meself...
--
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They don't anymore, and for a reason.

For a reason.

Your opinion isn't going to matter if someone gets hurt. It's a lot easier to wire a separate circuit.

Their lawyers are dumber than stumps if they think paperwork is going to get them out of the inevitable lawsuit. Do they have a compliance (UL, etc.) mark on them?

You're perfectly within your rights to knowingly violate codes. No "grandfather" excuse here, either.
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snipped-for-privacy@gmail.com wrote:

...
Yes, that reason is Code. Having worked on various Standards groups over the years, there's a definite tendency to continue to make modifications simply for the purpose of appearing to continue to do something and thereby justify the existence of the body.
In the 100 years before, where's the overwhelming evidence it was ever a problem????
As I said, one can choose but it's certainly not a major actual problem or there wouldn't have been the history of successful applications (and lord knows how many still existing appliances????) w/o any issues.
When's the last time you _EVER_ heard of it being the cause of anything?
--
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The NFPA is known to write the "code in blood". Someone was injured or killed before the code was modified. Sure, you'll likely get away with it but it is *NOT* smart to knowingly flaunt the electrical code. Lawyers love it, even if you don't kill anyone.

Depends on your definition of "overwhelming". It was never a good idea to tie a current carrying conductor to the case of a device. That's essentially what you're advocating.

Absolute nonsense! There are many dangerous practices that are no longer acceptable. This is one.

When I was *nailed* off my MIL's dryer (after she'd been complaining for months I took a look at it). Had it a safety ground it would never have shocked anyone. The code wasn't changed for this one instance (that they never knew about).
Just don't do it, and stop telling others to violate safety codes! You're being irresponsible!
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snipped-for-privacy@gmail.com wrote: ...

I'm not "telling" anybody to do anything--I'm simply pointing out it's been common practice until quite recently.
As for your experience, there has always been an external safety ground supplied on driers; whether one bothered to hook them up is another matter.
I stand by my contention the 3-wire split circuit existed in such numbers for so long that if it were truly a dangerous practice it would have taken far less time than it did for it to finally percolate its way to the radar screen.
I'll also reassert given my experience on Standards committees there is that aforementioned need to find _something_ to modify...they finally got to the bottom of the barrel where this became one thing they could find to change.
again, imo, ymmv, etc., etc., etc., ...
And, yes, Code now mandates 4-wire connections; others make your own determination, I'm not advocating you violate Code willy-nilly but the subject of a work light on a drill press...
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There has not always been a grounded conductor on driers, only a grounding conductor. Unfortunately, in the olden days, the grounding conductor has been used as a grounded conductor as well for 120 volt loads, which can cause the frame (which is attached to the grounding conductor) to have a potential difference relative to earth. (if they didn't bother to hook up the "external safety ground" as you call it (NEC calls it the grounding conductor), the light in the dryer wouldn't work at all, so it's quite likely that they _did_ bother to hook them up in almost all cases).
Modern NEC requires both a grounding and a grounded conductor on 240v/120v split loads.
scott
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Scott Lurndal wrote: ...

Read what I wrote instead of looking for an axe to grind and to try to show how shumart thou art... :(
I didn't write "grounded conductor" I wrote "external safety ground"--two different things but the latter solves a large portion of the problems (but they were often never connected or to an adequate ground in practice)...
--
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But you are. By your saying that it's perfectly safe (it isn't) and just the "committies" doing something just to do _something_, you're telling anyone here who will listen to violate code.

Not always used, nor useful.

So you think it's alright to tell people to perform unsafe acts? They're "safe enough", even though they clearly are not, in the eyes of thoese with jurisdiction over such things.

So your lousy experience in some unnamed committee trumps all safety rules?

Ah, the disclaimer, where you tell people that its not your fault when their kid gets electrocuted.

As much as you may think so, fire/electrical codes are not there so "others can make their own determination".
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Another alternative is to add a second lamp of identical wattage and wire them in series.
--
There is always an easy solution to every human problem -- neat,
plausible, and wrong." (H L Mencken)
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On Tue, 1 Sep 2009 10:58:01 -0700 (PDT), " snipped-for-privacy@gmail.com"

I'm not sure if "dpb" was referring to me, or not, but I found that with my DP. Motor can be rewired for 240, but the wiring harness has no provisions for a neutral feed. The "stock" harness connects the work lamp across the two non-ground leads so that if the DP is plugged into a 120v circuit, the lamp socket sees 120. And if plugged into a 240v circuit, the socket sees 240v. I'd strongly suspect the OP's band saw is similar. He'll certainly find out if he rewires the motor for 240 and his work light (with a 120v bulb) burns very brightly for a very short time.
Several years ago, on the manufacturer's web site, the PDF manual for the DP, as a part of the diagram for rewiring the tool for 240, showed the work light socket being changed to connect across one hot lead and the EGC to provide 120 to the lamp. I went back to the site at a later date, and that part of the diagram was no longer there. It now shows only a configuration that connects the lamp socket across the non-ground leads with no direct connection to the EGC. I suspect the diagram was deleted as a result of UL requirements.
Using the EGC for an operational conductor does violate the current NEC. But, the NEC doesn't cover anything beyond the wall plug. It's only applicable to permanent wiring, so rewiring the DP (or band saw) to supply 120v from a 2+G 240 circuit doesn't technically violate the NEC unless the device is hardwired into the facility wiring. That doesn't mean it's any more or less safe, just that it's not covered by the NEC. That's according to my understanding of the scope of the NEC. Even if "plug in" loads was covered by the NEC, compliance would be impossible to enforce unless you had to pull a permit and get an inspector out every time you plugged the vacuum cleaner into the living room wall socket.
Using the tool's EGC for a neutral return will, as stated, energize the grounded portions of everything connected to that circuit, as well as everything on every circuit which has an EGC connected to the ground bus in the panel that houses that circuit. The voltage on those energized grounds will be the product of the resistance to ground of the panel's ground bus times the current flowing from the ground bus to ground. May or may not be dangerous depending on the amperage and the resistance to ground.
Incidentally that is the same condition that exists if any device drawing current through that panel develops a short to ground. Until the breaker trips (assuming the leakage to ground is enough to trip the breaker) every grounded item in, or connected to, that panel will be energized with that amps x resistance voltage.
The use of GFI breakers addresses that condition by tripping anytime there is a very small difference in the amperage in the two non-EGC conductors. Otherwise the fault current would have to be on the order of the breaker rating. A DP or BS rewired to use the EGC as neutral on a 240v circuit would certainly trip any 240v GFI breaker that monitored the current in the two hot wires the way a 120v GFI breaker monitors the current in the hot and neutral wires.
Tom Veatch Wichita, KS USA
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Tom Veatch wrote: ...

...
Yes, it was you, Tom; that's the description I recalled, just couldn't recall who...
I'm willing to bet that's the same scenario OP has--a machine built before the change and documentation of same removed to avoid the issue from their end.
--
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In article <a317577e-a0a0-4b1b-a433-5c114f137e77

Heh heh, I had that kind of experience when I converted my arc welder from 230V to 400. No more sticky electrodes! (NB: I'm not in the US, 230V is our 'normal' voltage).
I believe 400V on a thicknesser is a nice thing to have, too. My fairly light German over and under planer/thicknesser has just about done its dash; and it doesn't owe me much either after 26 years. I might give that a second thought.
-P.
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I am no electrical expert but iIwould guess it will work OK. If you have normal residental home wiring you will actually have 2- 110 volt lines going to your BS. Add them up and you get 220 volts. The lamp will probably continue to have 1 single 110 volt line going to it.
Electric ovens and ranges have the same set up.
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What he said. I'm in Baltimore and on the same lines as you, Dave.
Ed
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Good point Leon. I know in a 4 wire 220 supply you can have two hots, a neutral and a ground. The outlet and plug will only have a 3 wires (2 hots and ground). I haven't pulled the plate off of the motor yet, maybe there is more info there. I am a bit shocked (no pun) that Powermatic's site doesn't have much support.
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It'll work but it's against code and (somewhat) unsafe. To split off 120V you need a neutral.

Electric ovens have a neutral, or at least they do now.
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OK. If you have

It'll work but it's against code and (somewhat) unsafe. To split off 120V you need a neutral.

Electric ovens have a neutral, or at least they do now.
Correct, I was just trying to point out a logical picutre. Absolutely they have neutral lines.
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