220 wiring question for saw & dust collector

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I just bought a saw and dust collector and they both run on 220. The question I have is, would it be OK for me to use 10/3 and a 30 amp double breaker and put both devices on the same circuit and be able to run both of them at the same time? I would not turn them on at the same time. I would let one get up to speed and then turn the other one on. I want to save the other 5 spaces in my 100 amp sub panel (in which my electric stove is also connected to) I have for lights and other outlets for tools. I am in the process of building a shop in my basement. I just moved into a new home. Thank you all for your opinions.
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One word: subpanel. Okay, two words, if you spell it: sub panel.
Solves all of your problems. Since your shop is in your basement and your load center almost assuredly is too, it'll be duck soup.
- - LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
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of
the
Grizzly states the following in the manual for their G1029Z Dust Collector: Circuit Breaker: The 2 H.P. motor will draw roughly 12 amps @ 220V. We recommend using a 20 amp circuit breaker. Circuit breakers rated higher will not adequately protect the motor.
I suppose this is true with any 220 amp motor.
Gary
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double
would
also
the
home.
Collector:
will
Ooops!! I mean 220 VOLT motor, obviously.
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They don't provide overload protection? How did this product get a U/L listing?
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Awright Greg, let's see if an extreme example will clear this up for you. Let's say you could find a 1000 amp breaker and installed it on the circuit in question. Now let's say that something goes horribly wrong with the motor and it starts drawing 200 amps ("cause it found a wrong ground or something) The wiring starts to catch fire along with the surrounding structure, but the 1000 amp breaker (or even the unrecommended 30 amp breaker) thinks everything is just dandy, so it keeps that (or some other excessive) current supplied to the fault in progress. Now if you had minded the warning that 20 amp protection would be correct and proper, it would have tripped and the fire department wouldn't be on the way.
Hope this helps

will
listing?
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I said earlier, it is clear that article 430 may simply be too complicated for most folks but I will try again. Start with the nameplate (FLA) rating of the motor. (for example 16a) Multiply this number by 1.25. That is the ampacity requred for the wire. You can use table 310.16 for this (14ga is OK for 20a at 60c)
Now take the FLA and multiply it by 2.5, that is the maximum size of the branch circuit overcurrent device. (40a) Some motors can have higher O/C devices, up to 11 times the FLA but you folks are confused enough. You have only sized the wire and the branch circuit O/C device at this point
NOW you need an "overload" device sized to the motor and some kind of thermal protection (may be the same thing) This is what protects the motor from burning up. Usually that is built into the motor or the equipment the motor is in. It may also be part of the motor starter assembly.
You also need a disconnect.
In your case the motor would have to have a 400a FLA to allow a 1000a breaker and you would need 1500Kcmil wire although most folks would just parallel two 350Kcmil.
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"Bob Jones" writes:

circuit
minded
I'm certain your description above is well intended; however, what it truly illustrates is your lack of the NEC and it's intended purpose.
The motor you describe could turn into burned toast, the NEC could care less as long as the insulation on the conductors feeding the motor is not damaged.
Circuit protective devices are designed to protect insulation on conductors, not the loads such as a motor, that consume the power.
Overload devices provide that function.
HTH
--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the Southland)
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truly
less
conductors,
Lew - your point is well taken and it has never been disputed in any of the recent threads on this topic. However - the discussions have not been about what NEC is intending to do. The electricians (or seemingly so) in the group keep referencing NEC and the fact that NEC intends to protect the wire not the device. The points that have been made about protecting the motors represent the *owner's* concerns. Not everything in the world of electricity is covered by NEC's interest. Owners have other interests besides their house wire. To date, I've not heard any of the electricians argue that the statements about properly sizing a circuit to the load is improper. The owner is concerned for his saw motor. It appears from the Griz literature that he should be. Maybe there is an error in the Griz literature, but to repeat that NEC only cares about wire insulation really does nothing to further understandings in these threads.
--

-Mike-
snipped-for-privacy@sprintmail.com
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I addressed that and pointed out 2 12a motors on one 30a circuit will actually provide MORE protection than one on a 20a. The reality is the NEC does talk about protecting the motor. That is the overLOAD protection that should be integral to the equipment. If your overloaded motor is tripping the wall breaker you either have the circuit overcurrent device sized TOO SMALL or the overload protection is not working. The overload should trip first if things are sized "properly".
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I am confused after reading all the replies. So folks what should I do for my Grizzly 12 amp saw & 12 amp DC, go with (2) 220 separate 20 amp breakers 1 for each device using 12/3 for each, or go with 1 220 30 amp breaker using 10/3 cable and putting them both on the same circuit? Thanks again.

actually
not
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Your choice, either way will do fine and both are legal. A am still not sure why you want 12/3 or 10/3. You can use 2 wire with ground. Just reidentify the white with some black tape.
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I msut have missed the earlier messages but I would use two 20 amp circuits. Two 12 amp motors starting at the same time would probably trip a 30 amp breaker. Thats assuming the 12 amps is running amps as oppossed to starting amps. See NEC 430 for code requirements for motors.
MikeM

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"Jim" writes:

(2)
same
Use a 2P-30A c'bkr and #10 AWG for each device.
Eliminates any inrush problems and keeps the voltage drop down.
--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the Southland)
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I'd go with the 10/3 and 30 amp. One point is that neither of these devices is of the kind you leave to operate unattended. If you're saw is overloaded and its built in protection fails to intervene, hopefully you're paying enough attention to notice "something's not quite right" and not be depending on the branch circuit protection to come into play.
bob g.
Jim wrote:

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actually
not
Aha - my apologies Greg - I missed that when you first posted it. I've been following the threads on this pretty closely but then again sometimes earthlink (sometimes...???) drops posts along the way.
--

-Mike-
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I previously wrote:

"Mike Marlow" writes:

the
about
wire
motors
<snip>
Read my LIPS:
Overload devices provide that function.
--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the Southland)
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I was under the impression that your house breaker is only supposed to protect the house wiring, not the device? Doesn't Grizzly have any overload protection? Mark L.
Gary wrote:

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There is no harm to running 10/3 rather than 10/2, but unless your machines actually require a neutral you don't have to.
You have not mentioned what the machines draw, but unless they are huge 30a should be plenty; I run both of mine on 20a.
You will have to use receptacles rated for 30a, but other than that it seems pretty straight forward.(though I would rather see two 20a circuits..)
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He didnt mention with ground, It needs a ground of course. I would check on the distance and current draw with a meter. I use all 12/3 with a ground. All my tools are within 30 feet of the panel. A cheap amp-probe can be a real eye opener on some of these 5 HP motors. It can also be used to tell if the start capacitor is bad on a motor.
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