Thank you in advance!

I am wiring up a 110V outlet to go on the side of my table saw outfeed
extension table recently built.
I would like to tap this off of the 220V outlet for the table saw, directly
beneath the new bench.
I know I can get 110 from this by putting the black wire on one of the 220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

Steve

Steve McDonald wrote:
Thank you in advance!

I am wiring up a 110V outlet to go on the side of my table saw outfeed
extension table recently built.
I would like to tap this off of the 220V outlet for the table saw, directly
beneath the new bench.
I know I can get 110 from this by putting the black wire on one of the 220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

No, it should go to the ground connection. If your 220V outlet does
not have a ground wire, then make the 110V outlet a GFCI type.

Bill Ranck
Blacksburg, Va.

wrote:
Steve McDonald wrote:

I am wiring up a 110V outlet to go on the side of my table saw outfeed
I know I can get 110 from this by putting the black wire on one of the 220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

No, it should go to the ground connection. If your 220V outlet does
not have a ground wire, then make the 110V outlet a GFCI type.

I forgot, leave the green wire unconnected if you don't have a
real ground connection. Do not connect it to the neutral wire.

Bill Ranck
Blacksburg, Va.

No, it should go to the ground connection. If your 220V outlet does
not have a ground wire, then make the 110V outlet a GFCI type.

I forgot, leave the green wire unconnected if you don't have a
real ground connection. Do not connect it to the neutral wire.



What are the ramifications of putting them together?

Could I just screw the green wire to the 220v outlet's grounded case since
there is no availible prong to use for this?

Steve McDonald wrote:

No, it should go to the ground connection. If your 220V outlet does
not have a ground wire, then make the 110V outlet a GFCI type.

I forgot, leave the green wire unconnected if you don't have a
real ground connection. Do not connect it to the neutral wire.

What are the ramifications of putting them together?

Could I just screw the green wire to the 220v outlet's grounded case since
there is no availible prong to use for this?

First, it's a code requirement that neutral and ground
only be connected a *one* place, generally at the service
entrance. The practical reason is that connecting them
together in other places can cause ground loops and this
can put voltages onto grounded metal cases. Not good.

If your 220V outlet case is truly grounded, then yes
you would connect the ground lead to the metal
case. This might be the situation if you have metal
conduit leading to the 220V outlet. You could do
that and also use a GFCI, then if the case isn't
grounded you are still OK.

Bill Ranck
Blacksburg, Va.

If your 220V outlet case is truly grounded, then yes
you would connect the ground lead to the metal
case.

Is there an easy way to check if it is truly grounded or not?

wrote in message ...
Steve McDonald wrote:
Thank you in advance!

I am wiring up a 110V outlet to go on the side of my table saw outfeed
extension table recently built.
I would like to tap this off of the 220V outlet for the table saw,
directly
beneath the new bench.
I know I can get 110 from this by putting the black wire on one of the
220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord
going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

No, it should go to the ground connection. If your 220V outlet does
not have a ground wire, then make the 110V outlet a GFCI type.

Bill Ranck
Blacksburg, Va.

Wrong answer. That does not keep a fault between the neutral and ground
from lighting up the frame of the saw with 110v. You need to have a four
conductor plug and wire, and the white wire on the 110 plug should be
completely separate and isolated from the ground connections of the saw
frame. The ground of the 110 should still be connected to the ground of the
saw. If you want to use a GFCI, by all means, do.

To be completely right, the receptacle should be wired with 4 wires, all the
way to the box, with separate ground, neutral, and two hot feeds.
--
Jim in NC

You just can't. Your 220 v outlet doesn't have a white (neutral) does
it. Do it right or just don't do it.

Also I learned from Blair. Go big or go home.

John

Steve McDonald wrote:

Thank you in advance!

I am wiring up a 110V outlet to go on the side of my table saw outfeed
extension table recently built.
I would like to tap this off of the 220V outlet for the table saw, directly
beneath the new bench.
I know I can get 110 from this by putting the black wire on one of the 220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

Steve

Your 220 v outlet doesn't have a white (neutral) does
it.

Yes...it does

Steve McDonald wrote:

Your 220 v outlet doesn't have a white (neutral) does
it.

Yes...it does

Just because there is a white wire doesn't necessarily mean it is
neutral. What other colored wires are in the box?

--
Jack Novak
Buffalo, NY - USA
(Remove "SPAM" from email address to reply)

"Steve McDonald" writes:
Your 220 v outlet doesn't have a white (neutral) does
it.

Yes...it does

There are two types of outlets, three prong and four prong. Both have
a white wire connected to one of the prongs, but only one of them has
a neutral. On a three prong, the white is the other hot (black=hot1,
white=hot2, bare/green=ground). On a four prong, black and red are
hots, white is neutral, and bare/green is ground.

If you have a black/red/white four-prong, you can use either
black/white or red/white, plus ground, to safely power a 120v outlet.

"Steve McDonald" wrote in message
...


Your 220 v outlet doesn't have a white (neutral) does
it.

Yes...it does



Steve

Just because it is white does not mean that it is neutral. A lot of times
white is also used as a hot. Do you have a meter? Can you go to the other
end of the cable (panel box) and tell how it is wired?

Generally, you will not have a neutral wire in a 220v circuit as it has no
purpose

Frank

Yikes!
Steve,
snip now...should the green wire (in the cord going to the new outlet)
also go to the same post as the white / neutral since both are at ground
potential?

No. The green wire (safety ground) is to provide a direct path to 'ground'
in_the_event_of_a_failure. If you don't care if your 110 outlet is
'grounded',
simply leave it unconnected. You will only have an ungrounded outlet.
(Also a GFCI outlet is no good without a ground!)
However, your 220 outlet on the table should have a green or bare ground
wire. If it does not then you don't have a grounded outlet for your saw.
(Don't know why that would be, since it's pretty standard practice
nowadays).

Incidently, your additional outlet idea sounds OK for a lamp or some small
appliance. If you plan on using it for a drill or shop vac with the saw
running, you maybe plagued with CB nuisence trips from too much power drain
on one of the 220 legs.
It might be better all around to just wire the outlet separatly.

Wha'd ya think?
Jon Veeneman

"Jon" writes:

(Also a GFCI outlet is no good without a ground!)

This is incorrect. A GFCI operates by comparing the
current flow between the current carrying conductor
and the grounded conductor (aka neutral). If they don't
agree within some small percentage, the GFCI will
interrupt the current flow. While it is preferred that
it be grounded it is not strictly necessary to obtain
the benefit of a GFCI.

scott

In article ,
(Scott Lurndal) wrote:

"Jon" writes:

(Also a GFCI outlet is no good without a ground!)

This is incorrect. A GFCI operates by comparing the
current flow between the current carrying conductor
and the grounded conductor (aka neutral). If they don't
agree within some small percentage, the GFCI will
interrupt the current flow. While it is preferred that
it be grounded it is not strictly necessary to obtain
the benefit of a GFCI.

scott

How does the "Test" feature on a GFI outlet work without a ground? My
understanding was that it was just a high-resistance shunt from the hot
leg to ground. When you push the button, the hot leg draws a little
current, the comparitor sees a current differential and pops the
internal circuit breaker.

On the other hand, just because the "Test" feature doesn't work, doesn't
mean the rest of it doesn't work. On the third hand, it seems pretty
dumb to put a GFI outlet someplace and not hook the ground up. On the
fourth hand, it seems pretty dumb to ever install an outlet without a
ground.

Thank you for all of the advice, although some of it appears conflicting.
I have examined and traced the wiring from the in-slab 240V metal table saw
outlet back to the panel. Here is what I see:

There are 3 wires going into the saw outlet from the panel end: BLK, WHT and
GRN.
The BLK and WHT are connected to the two hot prongs while the GRN is
connected to the center pin as well as to the metal box.
These wires then go into the concrete slab through a pipe. I can't tell if
it is metal or plastic.
The wires re-emerge about 10' away in a junction box in the wall, From here
they connect with another cable that returns to the breaker panel.
This cable has a RED, BLK, WHT and BARE wire. It is connected to the saw
wire as such:
BLK-BLK, RED-WHT, BARE-GREEN. The WHT wire (from the breaker panel) is
capped off.

What are the new implications of the WHT wire not being employed? Is it safe
in this configuration?

Sounds like it should be re-wired with a 4 wire system as so many have
suggested.

Steve

"Steve McDonald" writes:
There are 3 wires going into the saw outlet from the panel end: BLK, WHT and
GRN.

No neutral there.

What are the new implications of the WHT wire not being employed? Is it safe
in this configuration?

Yes. The white is not needed for 240v operation.

This cable has a RED, BLK, WHT and BARE wire. It is connected to the
saw wire as such: BLK-BLK, RED-WHT, BARE-GREEN. The WHT wire (from
the breaker panel) is capped off.

This is correct. If you replace the wires from this junction out, you
could add the neutral and have the option of adding a 120v outlet or
two.

Tug on the wires going into the pipe while watching the other end. If you can
pull them out attach a stout cord to the far end and pull the wire out. Add a
red wire to the pack and pull them back. Then hook them back up matching the
colors and using the red/black for the hots. Look in the panel and verify the
white is connected to the neutral bar. Then you will be OK for your 120v
outlet.

In article ,
Steve McDonald wrote:


Thank you for all of the advice, although some of it appears conflicting.
I have examined and traced the wiring from the in-slab 240V metal table saw
outlet back to the panel. Here is what I see:

There are 3 wires going into the saw outlet from the panel end: BLK, WHT and
GRN.
The BLK and WHT are connected to the two hot prongs while the GRN is
connected to the center pin as well as to the metal box.
These wires then go into the concrete slab through a pipe. I can't tell if
it is metal or plastic.
The wires re-emerge about 10' away in a junction box in the wall, From here
they connect with another cable that returns to the breaker panel.
This cable has a RED, BLK, WHT and BARE wire. It is connected to the saw
wire as such:
BLK-BLK, RED-WHT, BARE-GREEN. The WHT wire (from the breaker panel) is
capped off.

What are the new implications of the WHT wire not being employed?

Simply that it is a 240V *ONLY* sub-run. That _connected_ WHT wire (going
towards the saw outlet) _should_ be tagged with some black tape, at *both*
ends, to indicate that it _is_ a 'hot' lead, and not a 'neutral'.


Is it safe
in this configuration?

Assuming everything else is done correctly, _yes_.


Sounds like it should be re-wired with a 4 wire system as so many have
suggested.

It's perfectly OK, as is, for a _240V_only_ device.

However, if you _really_ want that 120V outlet as well, then yes, you
_must_ modify the wiring from the saw outlet to the point where it
ties to that other cable. Note: you'll also have to investigate the wiring
between the outlet on the wall, and the saw itself. You may have to replace
_that_ wire, as well, to get a real 'neutral' all the way to the saw.

Getting a 'neutral' to the saw outlet will involve pulling another wire
through that pipe -- I'd recommend RED, using it for the 2nd hot, and
're-converting' the WHITE back to the 'neutral'. Be sure to remove the
black 'tagging' from both ends of the white lead.

There are some ways to do the 120V outlet, without pulling the additional
wire, *BUT*, they are contrary to building-code virtually *EVERYWHERE*,
and, regardless, are _extremely_ dangerous -- there are 'failure modes'
that can *kill* you, even if you don't touch anything connected to the
120V outlet.

"Steve McDonald" wrote in message
...


Thank you for all of the advice, although some of it appears conflicting.
I have examined and traced the wiring from the in-slab 240V metal table
saw
outlet back to the panel. Here is what I see:

There are 3 wires going into the saw outlet from the panel end: BLK, WHT
and
GRN.
The BLK and WHT are connected to the two hot prongs while the GRN is
connected to the center pin as well as to the metal box.
These wires then go into the concrete slab through a pipe. I can't tell if
it is metal or plastic.
The wires re-emerge about 10' away in a junction box in the wall, From
here
they connect with another cable that returns to the breaker panel.
This cable has a RED, BLK, WHT and BARE wire. It is connected to the saw
wire as such:
BLK-BLK, RED-WHT, BARE-GREEN. The WHT wire (from the breaker panel) is
capped off.

What are the new implications of the WHT wire not being employed? Is it
safe
in this configuration?

Sounds like it should be re-wired with a 4 wire system as so many have
suggested.

Steve

YOU are in LUCK!

You didn't say you had conduit to work with! Great!

First, verify one thing. The whit in the junction box that is capped off is
most likely the neutral you are looking for. Get a voltmeter and check some
things. 1.) The capped off white to the bare wire, with it set on AC
volts. Should read no volts. 2.) check red wire to ground, on AC volts.
Should be 118 or there abouts. Red wire to ground, AC, also 118.

If it checks that way, the white is the neutral. Turn off all of the
breakers to that area. You need to pull a red wire from the junction to the
outlet. Buy or rent or borrow an electrical fish tap, and take care to tape
up the hook so nothing sharp is exposed.

You then will go black-black, white to white, red to red, and green to bare
in the junction. At the outlet, (a new 4 prong receptacle) you will go
black to x, red to y, and white to z, and green (or bare) to g. Do the cord
to the saw the same way, with the black and red to the saw motor (switch),
and one of them to the 110 outlet. The white goes to the silver screw on
the 110 outlet, and is not connected to the saw or anything else. The green
goes to the ground screw on the outlet, and the frame of the saw, and to the
motor, if it has a separate wire.

I think I got all the details you need. Write more, if you need more help.
--
Jim in NC

"Steve McDonald" wrote in message
...


Sounds like it should be re-wired with a 4 wire system as so many have
suggested.

Steve




YES!
The only safe way to do it. Anything else is risking your life.
Greg

As you can probably see by all the conflicting replies, it would be a
whole lot easier to just run a new 110v circuit where needed.

In article , "Steve McDonald"
wrote:

Thank you in advance!

I am wiring up a 110V outlet to go on the side of my table saw outfeed
extension table recently built.
I would like to tap this off of the 220V outlet for the table saw, directly
beneath the new bench.
I know I can get 110 from this by putting the black wire on one of the 220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

Steve

--
Jedd Haas - Artist
http://www.gallerytungsten.com
http://www.antijazz.com
http://www.epsno.com

"Jedd Haas" wrote in message
...
As you can probably see by all the conflicting replies, it would be a
whole lot easier to just run a new 110v circuit where needed.

There are no conflicting replies by those who know what they are talking
about. They all say install a 4 wire system. I have it on one of my table
saws, and wired through a starter to turn it on and off with the saw. No
big deal.
--
Jim in NC

Got it! I will not jury rig anything. I will either abandon the bench outlet
or try to snake a 4th wire through and do it the safe way. I cannot put a
new dedicated 120v circuit through the slab. Thanks to all (except for one
goof) for the advice...maybe a life saved here today!

Steve

it will be a lot easier to pull that Romex out and add the wire instead of
trying to shove it in with the romex in place. Technically you should be
pullibng discrete conductors, labelled properly but the cops won't knock your
door down of you just strip the Romex jacket off and use the ones you have. You
won't believe how much easier it is to pull without that jacket.

"Steve McDonald" wrote in message
...


Got it! I will not jury rig anything. I will either abandon the bench
outlet
or try to snake a 4th wire through and do it the safe way. I cannot put a
new dedicated 120v circuit through the slab. Thanks to all (except for
one
goof) for the advice...maybe a life saved here today!

Steve



Before we all sign off on this, I didn't notice anyone discussing the
breaker amperage vs. the wire gauge you plan to use to wire up the 120v
outlet. If, for example, the breaker is a duplex 30 amp and the wire you use
to connect the outlet is 12 or 14 gauge, you might have a fire hazard in the
making.

Thanks Guy...I have come up with a new solution so I will not be doing the
re-wiring. I will just coil a short extension on the outlet box that I can
plug into the wall outlet about 5' away, without having to get out an
extension. I really don't anticipate using the outlet much. Good point re
wire guage.

Steve

Good call Guy.

Blair


"Guy" wrote in message
. ..

"Steve McDonald" wrote in message
...


Got it! I will not jury rig anything. I will either abandon the bench
outlet
or try to snake a 4th wire through and do it the safe way. I cannot put
a
new dedicated 120v circuit through the slab. Thanks to all (except for
one
goof) for the advice...maybe a life saved here today!

Steve



Before we all sign off on this, I didn't notice anyone discussing the
breaker amperage vs. the wire gauge you plan to use to wire up the 120v
outlet. If, for example, the breaker is a duplex 30 amp and the wire you
use
to connect the outlet is 12 or 14 gauge, you might have a fire hazard in
the
making.

I jumped in on this pretty late, but how many conductors are in the cable
you are using to power up your saw? I would be surprised if you actually
had a neutral going there, but if you did, you could pull 120 into a
receptacle. I wouldnt want it to be used at the same time the saw was
working though.


"Steve McDonald" wrote in message
...
Thank you in advance!

I am wiring up a 110V outlet to go on the side of my table saw outfeed
extension table recently built.
I would like to tap this off of the 220V outlet for the table saw,
directly
beneath the new bench.
I know I can get 110 from this by putting the black wire on one of the
220V
outlets hot post and the
white wire on the neutral ...now...should the green wire (in the cord
going
to the new outlet) also
go to the same post as the white / neutral since both are at ground
potential?

Steve

I jumped in on this pretty late, but how many conductors are in the cable
you are using to power up your saw? I would be surprised if you actually
had a neutral going there, but if you did, you could pull 120 into a
receptacle. I wouldnt want it to be used at the same time the saw was
working though.

You are correct...only 3 cables...no neutral, so 120 out of the question.
And no, I had not planned on running them at the same time. My fixed
extension is working just fine and a lot less hassle!

Steve