My house was built in the 1960's and is "electrically challenged."
Rewiring would be the optimal solution, except for the cost. ;-)

For now I'm trying to figure out if I can get a 220v dust collector
without rewiring. (The service box is maxed.)

My shop is right next to the laundry room. I already unplug the washer
and plug in a heavy duty extension cord to run my contractor saw -- I
found out the saw and shop vac on the same circuit can trip the breaker
halfway through ripping a 2"x4".

Any reason I couldn't build an extension cord to make use of the
220/110 of the dryer outlet, converting it to a standard 220 outlet for
a dust collector? Or is this A Very Bad Idea (TM)?

TIA.

-- Mark

It is not legal. Dryers, before 1996, were not required to have a separate
neutral and ground. You will be sharing them and that is a bad idea. You also
have the amperage problem.

"Gfretwell" wrote in message
...
It is not legal. Dryers, before 1996, were not required to have a separate
neutral and ground. You will be sharing them and that is a bad idea. You
also
have the amperage problem.


Dryers in Canada were. My house in Canada, built in 1979, had 4-prong stove
and dryer outlets.

I didn't pull the cover off the service but I assume the dryer is 20A...

They are usually 30.

I suppose it's just 3 wire, but maybe I could pulle something that
could handle the 220, 110 & ground.

If you can pull a new wire in why are we dancing around. Just put in a bigger
breaker, pull in some fat 4 wire and put a sub panel to serve the dryer and
your shop.
We beat that subject to death a few days ago but we can hit the high points
again if this is a possibility.

"Wilson Lamb" wrote in message nk.net...

Obviously, you shouldn't get into any hookups unless you know what you are
doing. Get a qualified pal to help if necessary. I worked on a TS the
other day. Someone had used a 240V plug, but it was wired to make the case
of the saw 120V above ground!! Hopefully the previous owner had miswired
their outlet to match. The scary part is that the TS was in a school shop!


That reminds me of visiting the shop that belonged to the brother of a
friend of mine. He had a rule: never plug white painted plugs into
red sockets or vice versa --- see they were all 110V connectors but
the red ones were wired 220V. He was very impressed that he a) saved
all that money avoid spendy 220 plugs and b) could use regular old
110V extension cords anywhere. Well you can guess where this is going
..... he plugs in two cords (one 110, one 220) and they are both orange
and indistinguishable on the other end........
Some years later the building burned down and nobody knew quite why.

hex
-30-

Gfretwell,

If you can pull a new wire in why are we dancing around. Just put in a bigger
breaker, pull in some fat 4 wire and put a sub panel to serve the dryer and
your shop.

;-) There's a large time & effort difference between making a short extension
cord & getting up in the attic where the the wild dust bunnies have free range.
The last time I was up there I almost came through the ceiling -- 40 year old
1/2" 3-ply plywood doesn't like my 250+ lbs... I wanted to try "fast" &
"cheap" first. ;-)

We beat that subject to death a few days ago but we can hit the high points
again if this is a possibility.

I just discovered this NG yesterday & I don't see the topic in my downloaded
messages. Do you recall the title? I can google group for the info.

Thanks.

-- Mark

Doug,

If by "maxed" you mean that there is no room to add additional breakers,
perhaps you could replace four existing breakers with two tandem half-height
breakers. This would give you the space to add a double-pole (220V) breaker
for your new dust collector circuit.

This has been done on one of the positions in the subpanel from the main box.
I'll look into it.

Thanks.

-- Mark

There's a large time & effort difference between making a short extension
cord

Take a look at the wire. It *may* be 10/3 with ground. If so you could do
something with it.

reg (Gfretwell) writes:

It is not legal. Dryers, before 1996, were not required to have a separate
neutral and ground. You will be sharing them and that is a bad idea. You also
have the amperage problem.

This only an issue if the item hooked to the circuit has a 120V motor
along with other parts that are 240V.

All of the 220V circuits in my new house are just 3 wire except the dryer
circuit. This all passed electrical inspection.

Brian Elfert

Wilson -- Your writing shows you know something about electricity. Let
me as a question about dust collection system grounding. I've done
enough internet searching and reading in books & magazines to know this
is a bit of a religious issue. ;-) Suppose for arguements' sake I'm a
member of the Grounders sect.

- A neighbor told me the grounding is "weak" in the houses in our 40
year old subdivision.

- What good does it do to attach a grounding wire to the body of a
double-insulated but no ground wire router?

- Likewise, attaching to a TS that is grounded but not plugged in
doesn't do any good.

- If my DC isn't plugged in all the time it won't be grounded
either.

Is there any reason to not separately ground the DC ductwork, such as
by driving a 6' copper rod in the garden outside the shop and running a
wire to it?

Thanks.

-- Mark

Is there any reason to not separately ground the DC ductwork, such as
by driving a 6' copper rod in the garden outside the shop and running a
wire to it?

Thanks.

-- Mark

The reason is this won't clear a ground fault. (trip the breaker)
The ground has to be bonded to the center tap of the utility transformer. This
is accomplished in your service panel via the main bonding jumper. A separately
driven rod is required to be bonded to the service grounding system by the NEC.

What they are probably telling you is that some of your branch circuits don't
have grounding conductors in the wiring method. There has not been a
sifgnificant change in the code in reference to grounding the service in close
to a century.
Homes that were built to "GI Bill" or FHA standards after WWII should have a
grounding conductor brought to the box but you still could have 2 prong
receptacles. You can pigtail a ground out to a 3 prong receptacle if this is
true. If the house was built to minimum code it may only have a 2 wire cable
serving the branch circuits. The only fix in that case is to run supplimental
grounding from the panel or to rerun the cable feeding the circuit.

In article , wrote:
Doug,

If by "maxed" you mean that there is no room to add additional breakers,
perhaps you could replace four existing breakers with two tandem half-height
breakers. This would give you the space to add a double-pole (220V) breaker
for your new dust collector circuit.

This has been done on one of the positions in the subpanel from the main box.
I'll look into it.

Then sell the used circuit breakers you removed on e-bay. No kidding. People
will buy them. Really.

--
Regards,
Doug Miller (alphageek-at-milmac-dot-com)

Gfretwell,

Is there any reason to not separately ground the DC ductwork, such as
by driving a 6' copper rod in the garden outside the shop and running a
wire to it?

Thanks.

-- Mark

The reason is this won't clear a ground fault. (trip the breaker)
The ground has to be bonded to the center tap of the utility transformer. This
is accomplished in your service panel via the main bonding jumper. A separately
driven rod is required to be bonded to the service grounding system by the NEC.

So what is your opinion of this solution, quoted from
http://cnets.net/~eclectic/woodworki...e/Ducting.html

Thanks.

-- Mark

--------------

Brent Dugan was the Maintenance Supervisor/Plant Engineer for a large 'Meltblown'
polypropylene manufacturer (oil sorbents) for 9 years. He shared his way to
eliminate those nasty static shocks:

"Our product was plastic and our conveying systems, both air and mechanical were
plastic. Polypropylene fibers traveling through 3" or 4" PVC piping creates
massive amounts of static electricity. Our problem was so severe that we had
sparks jumping 1 1/4" from our piping that would leave burn marks on your skin.
Our employees dreaded working with the equipment. We tried all of the available
methods you proposed and more; e.g., wire inside, wire outside, wrapped wire
outside, etc. We spent quite a bit of my company's money to try and solve the
problem with consultants and experts all to no avail.

I finally came up with a solution. It was so simple and inexpensive that you will
not believe it. As you stated, static is electrons building on the surface of an
object. Well, I solved the problem by sticking 2" wide aluminum foil tape to the
outside and inside of the PVC piping and then grounding that tape. Putting the
tape on the outside of the piping was easy, just stick it on. Unfortunately that
was not enough and I also had to put a strip of tape on the inside of the duct.

Putting the tape on the inside was an interesting challenge. I wanted my tape
inside and tape outside to end up right next to each other with just the PVC in
between so I could use a screw and nut to ground the two layers together. I was
only able to make the aluminum tape with a backing like double-sided tape work on
the inside. To do so I started by sticking the aluminum tape to the bottom edge
of the PVC pipe. Slightly peel the backing and adhere the aluminum tape to the
end of a piece of 1/2" emt, conduit pipe, or other long rod. Feed the aluminum
tape through the pipe as you unroll it from the roll. When you have the tape
through the PVC, stick the aluminum tape to the end of the PVC pipe. Now 'tape'
the backing to the rod then stretch the aluminum tape tightly angling it towards
the top of the PVC piping (12 o'clock position). This keeps it from sticking
prematurely. Now gently pull the rod out of the PVC which also removes the
'backing strip' off as you go. Keeping the aluminum tape stretched tightly lower
it to the bottom side of the PVC pipe. To smooth it onto the inside I slipped in
a longer piece of PVC and simply rolled that pipe inside to "iron" the aluminum
tape down.

Having the tape back to back made grounding easy. I drilled a hole near each pipe
end through both layers of foil, inserted a 1/4-20 screw from the inside of the
pipe, put on a nut to make a good circuit, then connected each section using 14
gauge wire. I connected each end with alligator clips to another strip of the
aluminum tape adhered to the concrete floor. That totally eliminated the massive
static electrical discharges and earned me a bonus!"

So what is your opinion of this solution, quoted from
http://cnets.net/~eclectic/woodworki...e/Ducting.html

Apples and oranges. Grounding static electricity is a different animal than
bonding against electrical faults. As he says, you can ground out a static
charge in the manner he described.

I connected each end with alligator clips to another strip of the
aluminum tape adhered to the concrete floor.

I am usually slow to jump on the "you need a sub panel" band wagon but from
what you have said here (out of circuits, questionable grounding etc) this may
be the best long term option. Then you would have the ability to install the
circuits you need in your shop and be assured that the grounding pins of your
tools are actually grounded.

If you are still going with the "extension cord" route, give me the name plate
rating of your dust collector (voltage, HP and FLA) and I will tell you how to
set it up.
The answer will probably start another fight ;-)
If your dust collector is 1HP or less at 240v you can probably use a 14ga cord
.... on that 30a breaker and still be within the code. (using the NEC article
430 rules)

I misspoke ... "2 HP or more"

danm dyslexia!

Mark Jerde wrote in message ...
Any reason I couldn't build an extension cord to make use of the
220/110 of the dryer outlet, converting it to a standard 220 outlet for
a dust collector? Or is this A Very Bad Idea (TM)?

I'm working on the same problem -- only have a 120V/15A service into a
detached garage and picked up gloat mode on a nearly new 3hp unisaw
at an estate sale for next to nothing gloat mode off.

I made up a 'cheater' cord to run from the range receptacle in the
house to the saw in the garage until I upgrade the electrical service
out there.

I'm assuming you've got a dryer receptacle on the wall for the
standard four-prong dryer plug. Have a look to make sure it has the
separate ground back to the panel.

Get a spare dryer cord, a receptacle that matches the plug on your DC,
and a steel box, matching cover plate, and box connector, if
necessary.

The dryer plug has the U-shaped ground prong, two straight prongs on
the sides for the main lines, and a L-shaped prong opposite the ground
for the neutral line.

Your 240V DC doesn't need the neutral line. Use a hack saw to cut off
the latter prong at the face of the plug. Cut the white wire off at
the other end of the cord. Then connect the two lines and ground wire
to the proper terminals on the receptacle for the DC plug. Do the
wiring inside a metal box. Run a jumper inside the box to ground it,
too.

The circuit is good for 30 amps, which is good for 5 hp or so. The
potential issue is that if your motor overloads, and doesn't have its
own overload protection, it'll cook long before the breaker trips.
This shouldn't be a problem on a dust collector, however.

Good luck,

Tim

In Canada, separate ground wires were mandated sometime in the late '50s or
early '60s. Outlets for ranges and dryers were made law in 1970, at the same
time they required all NMD cable to have 90 degree celsius insulation, 60
degree insulation was dropped. US was much later in requiring these
standards.

"Guy" wrote in message
...

"Gfretwell" wrote in message
...
It is not legal. Dryers, before 1996, were not required to have a
separate
neutral and ground. You will be sharing them and that is a bad idea. You
also
have the amperage problem.


Dryers in Canada were. My house in Canada, built in 1979, had 4-prong
stove
and dryer outlets.

Gfretwell wrote:
If you are still going with the "extension cord" route, give me the
name plate rating of your dust collector (voltage, HP and FLA) and I
will tell you how to set it up.

I currently have a Sears 110v shop vac which doesn't do too bad with my
sealed-up contractor saw and router table. But it would be overwhelmed by
what I hope to be able to afford in a little while, a joiner & planer.
Plus, I've been reading about the health hazards of micro-sized sawdust, and
according to the site below 800CFM is needed to suck up all the little
nasties.

http://cnets.net/~eclectic/woodworking/cyclone/

All the 800 CFM DS's need 220, which I don't have in the shop yet...

Thanks.

-- Mark

I still advise against trying to use the dryer circuit for any 120v loads but
if your dust cyclone is 240v you could just use a hard service cord, sized the
same as the manufacturer recomendation and put a dryer plug on it.

Gfretwell wrote:
I still advise against trying to use the dryer circuit for any 120v
loads but if your dust cyclone is 240v you could just use a hard
service cord, sized the same as the manufacturer recomendation and
put a dryer plug on it.

I'll remember that. Thanks!

-- Mark

" Wilson -- Your writing shows you know something about electricity. Let
me as a question about dust collection system grounding. I've done
enough internet searching and reading in books & magazines to know this
is a bit of a religious issue. ;-) Suppose for arguements' sake I'm a
member of the Grounders sect.

- A neighbor told me the grounding is "weak" in the houses in our 40
year old subdivision.

Questionable report. Who knows what he means. Someone talked about two
wire wiring, which is pretty common. I wouldn't worry about it except in a
kitchen or bath, where upgrading could be worthwhile. There should be a
good ground rod at the box.

- What good does it do to attach a grounding wire to the body of a
double-insulated but no ground wire router?

None. Did someone suggest it? Most such tools are plastic. Do you have
something else?

- Likewise, attaching to a TS that is grounded but not plugged in
doesn't do any good.

Are you talking about the duct ground for spark suppression? No, the TS
won't isn't a ground if not plugged in. Interestingly, it may have enough
leakage through a concrete floot to suppress static buildup, even if not
plugged in. This is spooky stuff and explosions are rare, but it's easy to
do the grounding and be sure.

- If my DC isn't plugged in all the time it won't be grounded
either.

True, but so what? If it isn't running it can't build up static???

Is there any reason to not separately ground the DC ductwork, such as
by driving a 6' copper rod in the garden outside the shop and running a
wire to it?

No. Any sort of ground will do it. If you have a neutral connected to the
body (3 wire cord), just take the static collecting wire to the frame of the
DC.

I like someone's idea of the subpanel to serve the dryer and shop. You
could mount it at the dryer location and run wires to outlets in the shop.
Check the feed. It's probably 10 ga for a dryer. That's rated at 30 A, but
can do 40 in tool service, although that's not "legal". I think the 30 A
main we discussed, either in the main box or in the sub will do you fine. I
don't remember if your DC is 120 or 240, but if it will run on a house 120V
circuit you would have the 240 V circuit for big tools. Otherwise, you'll
have to do both on 240, which is probably OK.

I looked back and find your question ambiguous. Are you running the saw on
120 from the dryer outlet, or 240? I'm sure the vac is 120. If you don't
have the DC, just put the saw on 240 and you're there. Rigging the panel
and a couple of plugs will be nice for you and make you ready for a big
planer! Don't forget, you can also put in a 120V 30A circuit if you need it
for a tool that won't go on 240.

Good luck and let me know if you need help,
Wilson



-- Mark

"Mark Jerde" writes:

wrote:
I'm assuming you've got a dryer receptacle on the wall for the
standard four-prong dryer plug. Have a look to make sure it has the
separate ground back to the panel.

Nope, three-prong. :-( Same with the range, IIRC. I suspect I'm going to
have to do this "right."

Talk to a real electrician or go to Home Depot/Lowes/whatever and read a
book on wiring. You only need three wires for a 220V circuit.

Modern dryer circuits have four wires because a dryer has both a 110V
motor and controls and a 220V heating element.

Your dust collector only needs 220V with no 110V. Your dust collector
will work fine if you make an extension cord with a dryer plug on one end.

Brian Elfert

Really you only need two. The third is a safety ground.



Brian Elfert wrote:

"Mark Jerde" writes:

wrote:
I'm assuming you've got a dryer receptacle on the wall for the
standard four-prong dryer plug. Have a look to make sure it has the
separate ground back to the panel.

Nope, three-prong. :-( Same with the range, IIRC. I suspect I'm going to
have to do this "right."

Talk to a real electrician or go to Home Depot/Lowes/whatever and read a
book on wiring. You only need three wires for a 220V circuit.

Modern dryer circuits have four wires because a dryer has both a 110V
motor and controls and a 220V heating element.

Your dust collector only needs 220V with no 110V. Your dust collector
will work fine if you make an extension cord with a dryer plug on one end.

Brian Elfert

Not quite. The four wire outlet has two hot wires (110 VAC each), a
neutral, and a ground. The older 3 wire plugs lack the ground. Even with
the 3 wire outlet, you can get 110VAC from connecting to either hot wire,
and the neutral.


Modern dryer circuits have four wires because a dryer has both a 110V
motor and controls and a 220V heating element.

you can get 110VAC from connecting to either hot wire,
and the neutral.


I have avoided saying it but this is "hold your nose" legal if you put it on a
GFCI.

As an owner of a 1962 house, I can tell ya that I had NO grounds connected
at any outlet, nor a ground pin on any outlet. On the rare occasion when I
run out of projects, I rewire the outlets in a room up to the current code.
Fortunately, my wires did have a ground wire, but it was never connected.
At least I have copper wires, unlike some coworkers.

My washer is now connected to a GFCI, but my drier still has the 3 wire
outlet, and consequently, it isn't grounded.

Since you bring it up, have you checked to see if a GFCI is rated for a 1HP+
motor? If you don't have water in your shop, why would you want a GFCI?

"Gfretwell" wrote in message
...
you can get 110VAC from connecting to either hot wire,
and the neutral.


I have avoided saying it but this is "hold your nose" legal if you put it
on a
GFCI.

If you don't have water in your shop, why would you want a GFCI?

The code says all 120v 15 or 20a receptacles in garages, unfinished basements
or out buildings shall be on GFCI.

More to the point of my post, it also says when there is no ground present the
only way you can use a 3 prong 120v receptacle is with a GFCI.
(No a GFCI does NOT require a ground to function)

As for motor loads, the code requires GFCI protection on most spas and they
usually have big motors.
I have GFCI protection on all 120v circuits in my shop with no problems.

"Gfretwell" wrote in message
...
If you don't have water in your shop, why would you want a GFCI?

The code says all 120v 15 or 20a receptacles in garages, unfinished
basements
or out buildings shall be on GFCI.


Well, dammit, I didn't know that! :-) Found this online: "According to
the National Electrical Code, all garage-wall outlets must be GFCI outlets
or standard outlets protected by GFCI circuit breakers"
(http://www.thisoldhouse.com/toh/prin...216662,00.html)

I have a LOT of outlets in my garage/workshop. I might consider getting a
GFCI breaker rather than rewire all the outlets (or daisy chain some).

More info I found online: Workshops - Of special interest to the DIYer.
Your workshop, when in a garage or outbuilding with a floor at or below
grade, must have GFCI protection on the 120 - volt receptacles. A 1999
change to the code dropped the word "unfinished" in reference to workshops
and storage areas in garages and accessory buildings. So don't think that
just because your shop has a finished floor it meets the code. Most
workshops have a concrete floor, which tends to hold moisture, which
increases shock potential and isn't considered "finished" for the code.
Basement workshops follow the rules for basements. Two hundred twenty -
volt outlets aren't specifically addressed in this part of the code.
However, in a workshop setting they're generally for large machinery like
table saws. Because the outlets will not accept a standard 120 - volt
appliance cord, they fit the "not readily accessible" exception.
(http://www.handymanclub.com/document.asp?cID=55&dID=862)

Learn something new everyday.

I have a LOT of outlets in my garage/workshop. I might consider getting a
GFCI breaker rather than rewire all the outlets

You just need to put a receptacle GFCI in the first outlet in each branch
circuit, connect the outgoing wires to the "load" terminal.
If you have "home run" each receptacle that won't be as easy and the breaker
route may be an easier, if more expensive, solution.
From a real world perspective, the most important outlets are the ones that you
will be using line powered hand tools on. "Fixed in place machines" with line
cords safely routed out of the way are significantly safer than a hand tool
that could have a damaged cord, missing ground pin or whatever. There is an
exception to the GFCI rule that would cover the fixed in place equipment if
there are no other accessible outlets on that circuit.
You are also more likely to be sitting on the concrete floor when you are using
that hand held tool. This can provide a very dangerous fault path through your
body and that is why the GFCI rule was implimented.