Whole Shop And Machine-specific Help For Dunce

I wondered about the best approach and where GFCI should be used in the shop.

A couple of options
  • One or more GFCI breakers in your single phase panel
  • A GFCI outlet in each 120V circuit.

So basically, the 240 3phase to power the lathe motor, but we're just going to do a separate circuit altogether for controls/accessories. That actually makes good sense. Does this mean I'll need like a "master power on/off" for the 120v control circuits?

If you plug it into an outlet, a master switch is not really needed. The way I do it on my lathe is the E-stop switch serves as the ''master''. On my mill, I do have a master switch for the 120V power, but it's not really needed since it plugs into the wall. The switch was in the panel when I got the mill and would require actual effort to remove it.:grin:

Speaking of wall receptacles for 120V, buy the good ones, 20 Amp, industrial or heavy duty. They are about $5 each vs. the $0.95 ones, well worth the price difference in the long run.

I just wasn't understanding where.,. If my 3 phase is in one panel, my single phase in another...
That would be difficult to install.;)
 
A couple of options
  • One or more GFCI breakers in your single phase panel
  • A GFCI outlet in each 120V circuit.

If you plug it into an outlet, a master switch is not really needed. The way I do it on my lathe is the E-stop switch serves as the ''master''. On my mill, I do have a master switch for the 120V power, but it's not really needed since it plugs into the wall. The switch was in the panel when I got the mill and would require actual effort to remove it.:grin:

Speaking of wall receptacles for 120V, buy the good ones, 20 Amp, industrial or heavy duty. They are about $5 each vs. the $0.95 ones, well worth the price difference in the long run.


That would be difficult to install.;)

Thanks Jim!

As far as 120v receptacles, yes, absolutely, 20 amp high quality will be used. Our rinky-dink shack(also known as our home) has the world's cheapest crap outlets, 15 amp, and they don't hold a power cord even against the gravity weight of the end of the cord. I hate those cheap outlets. I've replaced a couple of the more annoying ones over time, but yes, in the shop, all good stuff for outlets. I just have to think about the number of times I've had to walk back and re-plug something in the shack because the plug fell out of the darned things. This isn't as big a problem with grounded plugs, but on simple stuff with no ground prong, it's a nuisance.

I definitely want to do the GFCI breakers, and I've always liked the idea since they came along. I especially like them wherever moisture is even a remote possibility, like near sinks, outdoor outlets, etc. What I really like is that if you have multiple outlets on a single circuit, a single GFCI receptacle provides protection to the whole circuit.

Thanks!

Mark
 
I definitely want to do the GFCI breakers, and I've always liked the idea since they came along. I especially like them wherever moisture is even a remote possibility, like near sinks, outdoor outlets, etc. What I really like is that if you have multiple outlets on a single circuit, a single GFCI receptacle provides protection to the whole circuit.
If you like crap outlets you'll love GFCI receptacles, especially the ones that can be daisy-chained as you describe. The target market is developers trying to comply with code at minimum cost. They fail frequently: a friend actually had one catch fire. I suggest that you either buy real GFCI breakers or do without. If all your 120V stuff is either three-wire or double-insulated I suggest that you consider Class C GFCIs (20ma rather than 5) to reduce nuisance tripping. And, of course, buy quality which in breakers pretty much means Square D.

[Edit] Here is an informative document: http://www.csemag.com/single-article/ul-s-new-gfci-classes/89c8746cdc4a7fd8a3cb93f1d51ba57a.html
 
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John, I know what a handle tie is. I just wasn't understanding where.,. If my 3 phase is in one panel, my single phase in another... Or am I missing something again? Sorry...

Mark
Can't be done with out relaying (you don't want to go there). You'll have to rely on prominent labeling. I suggest two neon or LED pilot lights, one powered by each circuit, on the panel of the machine.
 
If you like crap outlets you'll love GFCI receptacles, especially the ones that can be daisy-chained as you describe. The target market is developers trying to comply with code at minimum cost. They fail frequently: a friend actually had one catch fire. I suggest that you either buy real GFCI breakers or do without. If all your 120V stuff is either three-wire or double-insulated I suggest that you consider Class C GFCIs (20ma rather than 5) to reduce nuisance tripping. And, of course, buy quality which in breakers pretty much means Square D.

[Edit] Here is an informative document: http://www.csemag.com/single-article/ul-s-new-gfci-classes/89c8746cdc4a7fd8a3cb93f1d51ba57a.html
John,

Here are the 120 circuit breakers I intended to use: https://www.lowes.com/pd/Square-D-H...l-Function-AFCI-GFCI-Circuit-Breaker/50311123

All my panels are Square D. My meter bases, my main throw switch(on the service poles) are all Square D. So at least I got that right...LOL

Can't be done with out relaying (you don't want to go there). You'll have to rely on prominent labeling. I suggest two neon or LED pilot lights, one powered by each circuit, on the panel of the machine.

Yeah, that's what I thought. I figure I can do a master power indicator of some sort for the 120, and a motor power indicator like the machine originally had. I definitely don't want one more relay than I absolutely need...

Thanks!
 
Mark, not to speak in the place of Jim or John, who are much more knowledgeable than me when it comes to the code, I would stay away from AFCI breakers in general for the shop since it is detached from your house. In my house upgrade me and my electrician did last year, we tried to install several AFCI breakers. Could not get any of them to stay on, kept tripping. What we determined was any neutral wire that crossed over an hot wire, it would trip the AFCI breaker. We finally took them out. It's old work, code says, don't necessarily need them even though it is encouraged to install them. I do use GFCI breakers for my shop plugs and those outside the house. Ken
 
Mark, not to speak in the place of Jim or John, who are much more knowledgeable than me when it comes to the code, I would stay away from AFCI breakers in general for the shop since it is detached from your house. In my house upgrade me and my electrician did last year, we tried to install several AFCI breakers. Could not get any of them to stay on, kept tripping. What we determined was any neutral wire that crossed over an hot wire, it would trip the AFCI breaker. We finally took them out. It's old work, code says, don't necessarily need them even though it is encouraged to install them. I do use GFCI breakers for my shop plugs and those outside the house. Ken

Hmmm. I'll keep that in mind. I wonder why. BTW, my motor arrived in good order today, picked it up at the local freight terminal... Looks like a million bucks. Weighs like it too...LOL

Mark
 
Mark, not to speak in the place of Jim or John, who are much more knowledgeable than me when it comes to the code, I would stay away from AFCI breakers in general for the shop since it is detached from your house. In my house upgrade me and my electrician did last year, we tried to install several AFCI breakers. Could not get any of them to stay on, kept tripping. What we determined was any neutral wire that crossed over an hot wire, it would trip the AFCI breaker. We finally took them out. It's old work, code says, don't necessarily need them even though it is encouraged to install them. I do use GFCI breakers for my shop plugs and those outside the house. Ken
I agree. Don't use AFCI breakers in a shop. In fact, don't use them anywhere they aren't required, and perhaps not even there.
 
John,

Here are the 120 circuit breakers I intended to use: https://www.lowes.com/pd/Square-D-H...l-Function-AFCI-GFCI-Circuit-Breaker/50311123

All my panels are Square D. My meter bases, my main throw switch(on the service poles) are all Square D. So at least I got that right...LOL



Yeah, that's what I thought. I figure I can do a master power indicator of some sort for the 120, and a motor power indicator like the machine originally had. I definitely don't want one more relay than I absolutely need...

Thanks!
Ok. Just be sure the indicators are upstream of any on/off switches or contactors: they should be lit when the circuit is live even if the machine is turned off.
 
Ok. Just be sure the indicators are upstream of any on/off switches or contactors: they should be lit when the circuit is live even if the machine is turned off.
John, Right, that's the whole reason I'd want an indicator for the 120v control power, as opposed to just the spindle motor power indicator with which the machine was equipped from the factory. If I'm going to have a separate 120v circuit to control the rest of the machine, I need to know whether that circuit is also live. Just makes good sense. Since the machine did not have such a circuit originally, it's my thinking to place that indicator up top and apart from the originals. Makes it distinct...

Having mentioned that, I managed to unload the new motor from the truck this evening. Boy am I glad I have the tractor. Makes quick work of 300lbs. I'll probably fashion a sling to dismount the old motor and mount the new one so that I can use the tractor for the lift. I think this weekend, I'll be pulling off the old motor, and begin some serious cleaning before I mount the new one. A ton of work to be sure.

By the way, it seems odd that I am having trouble finding the GFCI-only circuit breakers to fit my single-phase panel. I can find used ones, but all the new ones are also AFCI, unless I happen to stumble into some NOS trove somewhere. I was reading on this a little, and that seems to be the way it's all going.

Thanks John!

Mark
 
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