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

I'm new to woodworking, and thought I'd try here for advice first.

I just inherited my grandfather's tools, and one of them is an old
Uniswaw. It's down in my basement now, and I would like to hook it up,
but all the outlets down there are two-prongers and the saw is
obviously three.

If I were to run a piece of wire from the cabinet of the saw over to
one of the exposed water pipes, would that be enough grounding for me
to be able to safely cut-off the third prong?

Also, if this is safe, how big a wire should I run? (The saw is 110
volts, BTW)

Thanks,
Greg

Does the house have well-water?

No, it's city water.

Hi, Greg.

From your question, it seems that you're kinda unfamiliar with
electrical safety.

I'd suggest you find a competent electrician who can:
1. determine what must be supplied to the saw, _and_ other devices that
might share a branch circuit,
2. install appropriately-rated branch-circuit a/r,
3. in compliance with NEC.

Nothing like an electrical fire in the basement.

HTH,
John

"Kinda" is not the word!! ("Completely" would be my choice)

Unfortunately, my house is a rental, and I know my landlord won't pay
to upgrade the wiring.

I would recommend you seek help from one of the forums dedicated to DIY
home wiring. I would personally recommend:

http://www.selfhelpforums.com/forumdisplay.php?f=12

and

http://forum.doityourself.com/forumd...0&daysprune=-1

It is only code-compliant to run a ground to the water supply system in
parts of Canada, and even then, it is not recommended. Do not cut the
ground prong off the plug. There are other, better ways to solve your
problem.

Steve

I'm not sure what you mean by a "troll." But I can tell you that I
don't think it's the original power cord. The cord looks a lot newer
than the rest of the machine does.

wrote in message
oups.com...
I'm new to woodworking, and thought I'd try here for advice first.

I just inherited my grandfather's tools, and one of them is an old
Uniswaw. It's down in my basement now, and I would like to hook it up,
but all the outlets down there are two-prongers and the saw is
obviously three.

If I were to run a piece of wire from the cabinet of the saw over to
one of the exposed water pipes, would that be enough grounding for me
to be able to safely cut-off the third prong?

Also, if this is safe, how big a wire should I run? (The saw is 110
volts, BTW)


Recheck The motor, and that would be the inside wiring, not just the
nameplate. Even our old R/I was wired 220, but it was capable of 110. Not
that _I_ would ever do it, but some people have "made do" when they
controlled both genders of plug.

Most basements, if wired to code, were grounded through the conduit, though
a lot of folks, as you can tell, have done their own wiring. Think it's
9.95 for a polarity/continuity/ground checker at most home stores. Well
worth it, because there are often hidden transitions to non-metallic pipe
where plumbing has been repaired or moved.

In article om,
wrote:

1. determine what must be supplied to the saw, _and_ other devices that
might share a branch circuit,
2. install appropriately-rated branch-circuit a/r,
3. in compliance with NEC.

Not speaking to the OP directly since I'm not confident of his/her
knowledge of basic electricals:

Another alternative - which may be more in keeping with the
landlord/tenant sitchiation - would be to run an *appropriately * sized
extension cord from an existing nearby correct voltage & amperage outlet
to the saw. This custom cord would have the saw's female plug
configuration on one end and the outlet's male plug configuration on the
other.
--
Owen Lowe
The Fly-by-Night Copper Company
__________

"I pledge allegiance to the flag of the
Corporate States of America and to the
Republicans for which it stands, one nation,
under debt, easily divisible, with liberty
and justice for oil."
- Wiley Miller, Non Sequitur, 1/24/05

No, because you don't know if the water pipes are grounded or not -
they could be PVC out to the street. They may or may not be bonded but
it's not something you want to find out the hard way. Get some 12-2
with ground romex and run a new line from the panel box to a new
grounded outlet. If you're not comfortable, have an electician do it.
Shouldn't cost much at all.

In article .com, wrote:
No, because you don't know if the water pipes are grounded or not -
they could be PVC out to the street. They may or may not be bonded but
it's not something you want to find out the hard way.

Right answer, wrong reason.

Right reason is that you don't want to do that because an electrical fault in
the saw could make the water pipes live. Bonding connections to metal interior
water pipes are *always* made for the purpose of *removing* electricity.

Get some 12-2
with ground romex

You have no idea how much current that saw draws, and therefore no idea
whether 12ga wire is suitable or not.

and run a new line from the panel box to a new
grounded outlet. If you're not comfortable, have an electician do it.
Shouldn't cost much at all.

Didja see the part where he said he's *renting*? He can *ask* the landlord to
do it, but if he does it himself (or hires it done) without the landlord's
approval, he's probably violating his lease, and may find himself needing to
look for other housing arrangements soon.


--
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?

In article .com, wrote:
I'm new to woodworking, and thought I'd try here for advice first.

I just inherited my grandfather's tools, and one of them is an old
Uniswaw. It's down in my basement now, and I would like to hook it up,
but all the outlets down there are two-prongers and the saw is
obviously three.

If I were to run a piece of wire from the cabinet of the saw over to
one of the exposed water pipes, would that be enough grounding for me
to be able to safely cut-off the third prong?

No. If you do that, and a ground fault occurs in the saw, you would electrify
the water pipes. It is *never* safe to ground a circuit to interior metal
water pipes.

It also is not safe to cut off the third prong.

Also, if this is safe, how big a wire should I run? (The saw is 110
volts, BTW)

First off, are you *sure* about the voltage? I thought Unisaws were all 240V
(but I could be mistaken about that).

Second, wire size depends on *current*, not on voltage. No offense is
intended, but if you didn't know that.... you shouldn't be trying to do your
own wiring. Especially since (as you said in a later post) it isn't your
house.

Check the rating plate on the saw's motor to see how much current it draws. If
the motor is really 120V, and the circuit can carry the current that the motor
needs, then you can ask your landlord to replace one of the receptacles with a
ground-fault circuit interrupter (GFCI). That will accept your three-prong
plug, and provide ground-fault safety even if the circuit isn't grounded.

--
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?

Are you sure it is 120v? Most motors over 1.5hp are 240v because the
current requirement is too high. And if it is 120v, do you have 20a outlets
in your basement? It is almost certainly over 15a. I suspect you will have
to put in a new circuit whether you want to or not.

Assuming you make it through all that, and you don't want to put in a new
circuit as someone suggested, and you don't have grounded conduit as someone
suggested; a GFCI outlet ought to be good enough.
There is no danger of a fire as a bunch of people said. The water pipe will
either be a really good ground or a really poor ground; neither will start a
fire. The issue is that you really don't want to get a shock while feeding
wood into a table saw. A GFCI should prevent that. I have only tripped a
GFCI once, but I didn't even feel it.

After putting in the GFCI outlet, you might want to attach a wire from the
frame to a water pipe, as you suggest. It may not be adequate by itself,
and it is certainly a code violation, but will act as a back up to the GFCI.
No matter how bad the connection it, it will certainly be better than the
path to ground through you. (I have said this mainly to annoy the
electrical-police, but it is actually true. Any current through the
"ground" (or through you, for that matter) will trip the GFCI instantly.)

Actually, I do have an idea how much that saw draws and 12-2w ground is
fine so be sure to have some cream with your big cup of STFU.
Yes, I did see that he's renting. I don't think that I need to spell
out every step. Did you see that I didn't tell him to be sure to strip
the ends of the wire? Didn't tell him to put a cover plate over the
outlet either. Jesus but you're a pain in the ass.

I just took off the motor cover and looked at the motor itself...it
also looks relatively newer than the saw itself, and the voltage is
listed at 110/220. I guess it's hooked up to 110, because it's a
standard 110v cord.

What's the amperage?

15/7.5

In article .com,
wrote:

I guess it's hooked up to 110, because it's a
standard 110v cord.

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
__________

"I pledge allegiance to the flag of the
Corporate States of America and to the
Republicans for which it stands, one nation,
under debt, easily divisible, with liberty
and justice for oil."
- Wiley Miller, Non Sequitur, 1/24/05

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?

wrote in message
ups.com...
15/7.5


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.

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.

wrote in message
oups.com...
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?


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.

In article , "toller" wrote:

After putting in the GFCI outlet, you might want to attach a wire from the
frame to a water pipe, as you suggest. It may not be adequate by itself,
and it is certainly a code violation,

Yes it is - so why are you advising him to do that?

Yet *another* example of why you have no business offering electrical advice.

but will act as a back up to the GFCI.

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.

No matter how bad the connection it, it will certainly be better than the
path to ground through you.

Further nonsense.

(I have said this mainly to annoy the
electrical-police, but it is actually true.

Even further nonsense.

Any current through the
"ground" (or through you, for that matter) will trip the GFCI instantly.)

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?

In article .com, wrote:
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?

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?

Is this something I should do? Will that make the saw more powerful?

No, it's just two different ways to get to the same place.

In article .com,
wrote:
Is this something I should do? Will that make the saw more powerful?

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' :)

On 16 May 2005 08:38:57 -0700, wrote:

I'm new to woodworking, and thought I'd try here for advice first.

I just inherited my grandfather's tools, and one of them is an old
Uniswaw. It's down in my basement now, and I would like to hook it up,
but all the outlets down there are two-prongers and the saw is
obviously three.

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?

If I were to run a piece of wire from the cabinet of the saw over to
one of the exposed water pipes, would that be enough grounding for me
to be able to safely cut-off the third prong?

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

Also, if this is safe, how big a wire should I run? (The saw is 110
volts, BTW)

Thanks,
Greg

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/=ADfor...lay.php?f=3D12


and


http://forum.doityourself.com/=ADfor...D1&so=ADrt=3D=
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

On Tue, 17 May 2005 00:23:04 -0000,
(Robert Bonomi) wrote:

In article .com,
wrote:
Is this something I should do? Will that make the saw more powerful?

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.

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

Master Woodbutcher and seasoned termite

Shamelessly whoring my website since 1999

http://www.woodbutcher.net

Proud participant of rec.woodworking since February, 1997

on 5/17/2005 9:51 AM Mr Fixit eh said the following:
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/*forum...1&so*rt=lastpo.

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/

George wrote:




Recheck The motor, and that would be the inside wiring, not just the
nameplate. Even our old R/I was wired 220, but it was capable of 110. Not
that _I_ would ever do it, but some people have "made do" when they
controlled both genders of plug.

Most basements, if wired to code, were grounded through the conduit, though
a lot of folks, as you can tell, have done their own wiring. Think it's
9.95 for a polarity/continuity/ground checker at most home stores. Well
worth it, because there are often hidden transitions to non-metallic pipe
where plumbing has been repaired or moved.


Just remember, those $9.95 checkers cannot detect neutral switched with
ground. This can be done by visual only.

Rob

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.

wrote in message
oups.com...
I'm new to woodworking, and thought I'd try here for advice first.

I just inherited my grandfather's tools, and one of them is an old
Uniswaw. It's down in my basement now, and I would like to hook it up,
but all the outlets down there are two-prongers and the saw is
obviously three.

If I were to run a piece of wire from the cabinet of the saw over to
one of the exposed water pipes, would that be enough grounding for me
to be able to safely cut-off the third prong?

Also, if this is safe, how big a wire should I run? (The saw is 110
volts, BTW)

Thanks,
Greg

In article , "Larry and Lois" wrote:
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.

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

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.

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?

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.

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

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.

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?

"Larry and Lois" writes:
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 wouldn't suggest this.

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.


Nor this.

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.


Say what?

it would be best to call an electrition to install. if you have no proper
knowledge of wiring.

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

and the land lord cant say anything if an electrition does it and you are
paying for it.

Whoops, spoke to soon.

scott


wrote in message
roups.com...
I'm new to woodworking, and thought I'd try here for advice first.

I just inherited my grandfather's tools, and one of them is an old
Uniswaw. It's down in my basement now, and I would like to hook it up,
but all the outlets down there are two-prongers and the saw is
obviously three.

If I were to run a piece of wire from the cabinet of the saw over to
one of the exposed water pipes, would that be enough grounding for me
to be able to safely cut-off the third prong?

Also, if this is safe, how big a wire should I run? (The saw is 110
volts, BTW)

Thanks,
Greg