I'm rewiring my TS for 240V...the motor is easy, since the diagram is right there
on the case. However, the switch has left me with one question. I picked up a
GE CR101 motor starter switch (ebay) and mounted an additional box on the front
the TS to hold the switch. However, there is no ground screw on the
virtually every other box-mounted switch I've had in my hands. There are three
terminal pairs on the switch...but I believe the 3rd terminal is for 3-phase
and that the ground wire should NEVER be switched.
There are screws holding the switch casing together that contact the front
I'm thinking that the ground wires from the power and the motor should be tied
together with a wire to this screw on the switch and another wire to the cabinet
of the saw. Sound right?
Need some care with the terminology here.
Have to differentiate between "neutral", and "ground".
Neutral wire is white; ground is green or 'bare'.
"Ground" is *NEVER* switched.
"Neutral" is usually _not_ switched, although *if*done*correctly* it is safe
to do so.
"Neutral" is *NOT* to be tied to 'chassis' or other grounding point, except at
the main service entry point.
"Ground" is intended to be connected to chassis/frame, etc.
I suspect you were calling the white wire 'ground'.
You don't have a neutral with 240V. You have two hots, both switched, and
ground. If you hook up with conventional romex house wire, You'll have
black and white. It's common to put some colored tape on the white at the
emds, to signal that it's a hot wire. Ground connected as described.
Be sure to use the set of contacts that are connected to the coil, otherwise
the relay won't pull in. One set will remain unused, if you really have a 3
Nope. None of mine are marked.
You look in a breaker box. You see a white stuffed in a breaker that has a
common trip. You says to yourself, self, that is a 220. The white be hot!
No problem here.
You goes to the other end of the wire, where it terminates in a box with
only one circuit, and has a funny lookin outlet, with prongs sideways, and
all. You says, self, this here be a 220 outlet, and when you opens up the
box, you see a white and black on the receptacle. No problem here.
See, even I didn't get cornfused, and I ain't the brightest bulb in the
Seriously, the only thing that needs to be marked is the white neutral
coming from your meter to the breaker box. And then that is usually black
wire with white tape or paint added to it.
Right, and I almost went there, and decided not to.
I have seen it done, where machines were being relocated, and a 110 needed
to become a 220, so rather than re-pull a new colored wire, a white was
marked with a piece of color tape at the box, and at the panel, and a new
double pole breaker installed with the color tape and the black wires.
There is an interesting opportunity for the original poster, now that he has
a magnetic starter. If you want to, you can add a 110 volt box on the side
of the saw, and have it hot when the starter is pulled in. Then you will
have to have a neutral, and a 4 prong plug.
I did this, so I could run a shop vac to the top of the guard, and catch
most of the dust coming off the top of the blade.
I guess I'm missing your point. If you're going to make a 'couple quick cuts',
you use the vac instead of the DC? What is the point in having both? Sounds
like a pain to have both a DC and a vacuum hooked up to the TS. If you have
a DC, why not split a smaller hose to the blade guard?
BTW, I am installing a "motor starter switch", not a "magnetic starter". I'm
not sure if that affects your original comment, but they are two distinctly
different things, as you are probably aware.
The DC only gets the saw dust that falls into the bottom of the cabinet, and
a little more. For a couple cuts, you can wait until the next time the DC
starts to get that.
Why I don't split off from the DC? A had a vac sitting around doing
nothing, and under the saw table was a good place to store it, then if it's
under the saw, why not put it to use? Plus at the time I didn't have a
remote DC switch. I see the switch instead of magnetic starter now, but you
could still do this with the switch, and adding an un switched neutral wire.
Speaking of remote DC switches. I did a REAL Rube Goldberg to get a remote
for the DC at the school shop, where I teach.
I had an old garage door opener that the father in law gave me for parts. I
got a couple single pole, double throw micro switches, and put them in the
unit, so that when the opener was cycled, and the limit screw and contacts
moved, it would hit either switch at the end of the travel. One switch I
wired so that the normally open got closed, and would energize the "hold in"
circuit on the magnetic starter, then the contactors on the starter would
also be holding it in. The other switch was wired so the switch at normally
closed would open when the screw traveled, and break the starter's hold in
circuit, to shut it off. Everything is neatly inside the box, away from
prying hands, and it is working great!
Part of the complication of wiring it this way, was so the DC could also be
started from a different shop. A bonus is, that once I have turned it on,
the kids in the other shop can't turn it off, like they used to do!
Anyone top that for a Rube Goldberg? :-) I'm sure someone can!
Listen to what he says.
Above all, don't be an idiot and wire your garbage disposal switch so that
it switches neutral.
It might appear to work, but strange things will happen if it shorts out.
After I moved in to my current residence, SHMBO asked me to remove a broken
light bulb from the chandelier. Darned If I didn't get
zapped. I double checked the light switch (I was quite sure it was off since
the other bulbs were not lit). After some
investigation, I found that the previous owner ( I sure hope not an electrician)
had switched the neutral rather than the hot.
In my experience, almost without exception, strange electrical behavior can
usually be traced to a neutral problem
Wire nut the motor's green to the power cord green, and to the box
(with a pigtail, if the box is metal).
Then connect two power cord wires (black) and (red) to the LINE side
of the switch, and the two hot motor leads to the LOAD side of the switch.
The power wire should NOT be HOT during this installation! Unplug it,
or pull the fuses, or turn off the disconnect switch.
Chris Merrill wrote:
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.