Electrical service - welder outlet work for tablesaw?

I recently moved my shop from a 2 car garage to a farm with a 25' x 30' shop - man what a difference! The electrical service has a 40Amp 3 prong outlet for a welder. I think this is 220V single phase.
Q1) Will this circuit work for a 220V tablesaw? Q2) If so, can I change the outlet to a standard 220 outlet and since it is 40A - run a large tablesaw and dust collector off of the same circuit?
Thanks for the help, Bucc
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Bucc wrote:

A1 yes but I'd change the breaker to 20 amp. If something were to happen with the saw motor the smaller rated breaker will hopefully kick off before damaging the motor of your saw where the bigger breaker may not kick off and you'll fry the motor.
A2 yes but you may have problems fitting the wire to the receptical terminals. You may have to pigtail the bigger wire with smaller wire to make the connection to the smaller rated 220 receptacle
Gary
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"GeeDubb" wrote in message

before
and
Yabbut, the breaker is not there to protect the motor, it's there to protect the insulation on the wiring. The motor should have its own thermal overload protection.
--
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A2A if you do this you *must* change to a breaker rated for the ampacity of the smaller wires. E.g. if you pigtail with #10 wire, use a 30A breaker; with #12 wire, use a 20A breaker; etc.
-- Doug Miller (alphageek at milmac dot com)
How come we choose from just two people to run for president and 50 for Miss America?
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Yes, it will work just fine for your tablesaw
Just change the plug on the end of the tablesaw cord to match the socket OR replace the socket with one that matches the tablesaw plug
Depending on the DC, you should be able to run both off a 40A circuit
John

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First, check for a fourth ground (green or bare) wire in the cable feeding the welder receptacle. If it's available, I'd put in a sub-panel. Run the green or bare ground wire to the ground bus in the subpanel, the white wire to the neutral bus, and DO NOT BOND the neutral to the ground (case) in order to maintain the non-current-carrying safety ground isolated from the neutral wire except where they connect in the main panel upstream.
Next connect the two 120-volt wires (black and red, usually) to the L1 and L2 lugs in the subpanel, then install a set of 240-volt, 20-amp breakers for your saw, another for your dust collection system (you are buying one of my kits plus blower, right? :-) After all, it's the best thing out there; see http://cnets.net/~eclectic/woodworking/cyclone/ClarkesKits.cfm for details).
Or, if you prefer, you can run #10 wiring to your table saw as well as the DC and use a single 40A 2-pole breaker if you have proper overload protection.
Overload protection and proper switching on motors is a critically important subject. I recommend you read my article detailing this important subject at
http://cnets.net/~eclectic/woodworking/cyclone/ClarkeMotors.htm
Most people are completely clueless about this topic, and put themselves and their shops and systems at great risk if they don't do it right. You MUST have proper overload and grounding protection to prevent fire, injury from electrocution, or even death.
Clarke
Bucc wrote:

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[snip]
[snip]
Speaking of clueless, Clarke... he almost certainly already has the grounding conductor (green or bare) in that 240V circuit. It's the neutral (white) that's probably missing.

-- Doug Miller (alphageek at milmac dot com)
How come we choose from just two people to run for president and 50 for Miss America?
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I can't imagine a 240V outlet with no neutral. Lots of devices have both 240 and 120V loads, like a clothes dryer. Even the welder probably had a fan. I'd put in some sort of box with three outlets! Is there a wall where you can put a small sub and some receptacles? There's enough power in that outlet to run a whole shop! BTW, why not get a welder? Just keep the welding away from the sawdust! Wilson
wrote:

sub-panel.
grounding
this
it is

Miss America?
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You must not have any 240V power tools in your shop. :-)
The original post specifically describes an outlet with *three* prongs. If it's a 240V outlet, those prongs are line, line, and *ground* -- IOW there is no neutral there. This is a _very_common_ situation.

And lots of 240V devices have *no* 120V loads, such as table saws, lathes, sanders, shapers, radial arm saws, dust collectors, etc -- and any 240V outlet supplying such a device doesn't need, and probably doesn't have, a neutral.

If it did, it was a 240V fan, because the outlet supplying the welder doesn't have a neutral.

40A at 240V is a bit thin IMO. Depends on what you want to power with it, I guess, and how many people are in the shop at one time. That's probably OK for a one-man shop, but it might not be if there might be several machines going at once.

-- Doug Miller (alphageek at milmac dot com)
How come we choose from just two people to run for president and 50 for Miss America?
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Sure there are. You see them all the time as air conditioner outlets, and it's also what most 240V shop machines (Unisaw, for example) use.

Sure. And those will use an outlet that supplies both. Check out
http://www.quail.com/nema.cfm
to see what's available.
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I read the on-topic ww posts with great interest and find that I learn alot.
However, when I read many of the OT post such as electrical installation, motor sizing, plumbing, etc, I find myself ROTFLMAO.
I just hope that people can filter the good info from the just plain dumb stuff and that no one gets hurt or worse.
-- Al Reid
"It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so." --- Mark Twain
wrote:

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[snip]

And in the same vein -- you've mis-attributed the quotation. It's from "Josh Billings," a pseudonym of Henry Wheeler Shaw. [Reference: Bartlett's Familiar Quotations]
-- Doug Miller (alphageek at milmac dot com)
How come we choose from just two people to run for president and 50 for Miss America?
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Doug,
That's interesting, since I found it here:
http://www.quotedb.com/quotes/1097
A google search shows many references indicating that the source was Mark Twain.
There was a similar quotation attributes to Will Rogers.
And there is this: "It ain't what you don't know that hurts you, it's what you do know that ain't so." (Variously attributed to Mark Twain, Josh Billings and Will Rogers.)
Just goes to show, you can't always believe what you read.
-- Al Reid
"It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so." --- Mark Twain
wrote:

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Checking the color just gives you a clue. To be sure, get out a voltmeter and see what's really on the wires. I've seen some pretty scary shit when it comes to people using whatever wire they had handy and to hell with the color code. Same with wiring up recepticles. Hot green? It happens!
This seems most endemic in small industrial settings. In a big plant, there's an electrical staff and enforcers to make sure only the electricians touch any wires. In a small shop, there's usually somebody around who knows just enough to be dangerous, and when something breaks, as long as he can get the machine turning again, the boss thinks he's a hero. Ditto for homeowners.
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