Please...need help...ONE last electrical discussion...

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Okay, it will run on a 15a outlet; I thought Unisaws had much bigger motors. It "should" be on a 20a circuit, especially if it is on the other side of the house from the breaker box, or if there is anything else on the circuit. But since you are renting...
A GFCI outlet should solve your problem.
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wood snipped-for-privacy@yahoo.com wrote:

Are you saying the plug is a standard 110? As in two vertical prongs with a round ground?
--
Owen Lowe
The Fly-by-Night Copper Company
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Yeah...just like a lamp/clock/etc.
And by the way, why does the motor list two numbers for the amps? I suppose that has something to do with the two voltages, but how can a motor draw two different amps?
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The motor uses 1800w. That is 15a/120v or 7.5a/240v.
Basically, at 120v there are two circuits in parallel; at 240v they are wiried in series. In series the resistance is 4 times as high as in parallel, and (since the voltage is twice as high) they draw half the current. Well, I thought this was pretty neat the first time I changed a motor over.
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Not to diss gramps, but make sure those wires are connected IAW the 110 setup. As I said earlier, it is not unknown that people make due with the receptacle/plug they have rather than the one which 220 would demand.
Toller finally got it right, twice the volts half the amps.
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wood snipped-for-privacy@yahoo.com wrote:

15A at 120V, 7.5A at 240V. To operate at 240V you must move a jumper wire which changes the internal wiring of the motor. Basically, you have two sets of motor windings, which are connected in parallel for 120V operation, and in series for 240V operation.
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
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Is this something I should do? Will that make the saw more powerful?
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No, it's just two different ways to get to the same place.
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Proverbial answer: "It depends". <grin>
If you have 240V readily available, converting to run at 240v will be *slightly* more efficient. "All else being equal", we're talking about a _few_ percentage points in improvement.
*HOWEVER*, some motors are rated at significantly higher output at 240V than 120V. E.g. the Baldour motor used on Delta contractor saws is rated at 1.5HP when run at 120V, and *2* HP when run at 240V. The nameplate power draw numbers are also consistent with the assymetric HP ratings.
If you can get an extra 1/2 HP , 'just by re-wiring', *and* you find yourself (at least occasionally) in situations where the 1.5 HP rating is 'not enough', converting to 240V *can* make a signficant difference.
(The only way to know for sure whether or not it will be beneficial _to_you_ is to 'try it and find out' :)
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On Tue, 17 May 2005 00:23:04 -0000, snipped-for-privacy@host122.r-bonomi.com (Robert Bonomi) wrote:

That particular Delta saw motor (and it's not on ALL Delta contractors saws) is the only convertible motor I've ever seen that had other than a twice/half FLA rating.
--
LRod

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Yes it is - so why are you advising him to do that?
Yet *another* example of why you have no business offering electrical advice.

Absolute nonsense. If the GFCI has failed, and a ground fault occurs, this will electrify the metal water piping, which is a _very_ hazardous condition.

Further nonsense.

Even further nonsense.

Not really. Ten milliseconds is pretty fast, I grant you, but it's not instant.
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
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wood snipped-for-privacy@yahoo.com writes:

No.
scott
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On 16 May 2005 08:38:57 -0700, wood snipped-for-privacy@yahoo.com wrote:

Ok, you just got a Unisaw for nothing. That saved you about $1500 that you can use to change the $.39 outlet. Why damage the tool when it only takes about 5 minutes to change the outlet out?

See above, get a grounded outlet, and one of those 6" green wires to ground the outlet to the inside of the electrial box.

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If you follow this thread it absolutely *proves* that although there is some sound electrical advice to be found in this forum, it is far from consistent. And how does a newbie to DIY wiring know the difference.
Like I said earlier....for help on wiring I would personally recommend:
http://www.selfhelpforums.com /forumdisplay.php?f=12
and
http://forum.doityourself.com /forumdisplay.php?f=9&page=1&sort=lastpo...
These are forums moderated by knowledgeable electrical professionals, so you can be much more sure of the quality of advice you get.
I keep wading through the flamers and the trolls and the evangelists because there is much to be found in the way of *woodworking* expertice here.
Steve
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on 5/17/2005 9:51 AM Mr Fixit eh said the following:

Both look to be good sites however drop the URLs to the minimum and you will actually be able to just click on them, thusly:
http://www.selfhelpforums.com /
http://forum.doityourself.com /
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Dont destroy your saw's cord. get an adapter, for the plug. my mother-in-laws house was built 1949 and has all 2 prong sockets. when i go there i carry my own plug adapter. so i can plug in my 3 prong laptop.
I would get a hammer drill and drill through the slab close to the plug you want to use, and drive a grounding rod into the ground. then put in a 3 pround plug with a wire attached to the ground rod.(carful not to hit any under ground pipes or conduits while drilling) or run the ground wire through the wall and put ground rod outside of foundation.
Dont use the water pipes, or any other pipe as ground. if it does surge, into the ground(i.e. the pipe) you will kill any one in the house useing the water or taking a bath.
it would be best to call an electrition to install. if you have no proper knowledge of wiring. and the land lord cant say anything if an electrition does it and you are paying for it.

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There's no ground-fault protection in those adapters, though.

Multiple problems with that idea, starting with drilling through the slab in a rental dwelling. It's doubtful that the landlord is going to be too happy with that.
Furthermore, Code requires any such ground rod to be bonded to the remainder of the building's grounding electrode system (typically another ground rod next to the service entrance). Seeing as how a grounding conductor would have to be run from that ground rod back to the service entrance *anyway*, it's obviously much less work to simply run a grounding conductor from the receptacle to the service entrance. If the circuit is in conduit (as I think the OP said in another post), that's trivial.
In any event... a ground-fault circuit interrupter: a) provides a Code-compliant three-prong outlet b) provides Code-*required* ground fault protection even if the circuit isn't grounded c) costs less than ten bucks d) can be safely installed by a layman e) is unlikely to meet with any objection by the landlord, as long as the tenant asks permission _first_.
So why look for more complicated and expensive solutions to the problem?

Correct advice, but the risk should be stated as "... may kill ...".

Quite wrong. The landlord owns the premises, and (unless the lease specifically states otherwise) any modifications to the premises would require his permission, regardless of who pays for them.
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
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I wouldn't suggest this.

Nor this.

Say what?

Now here is the first bit of good advice in this post.

Whoops, spoke to soon.
scott

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