GFCI protected circuits

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garys
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GFCI protected circuits

Post by garys »

Does anybody here run their Shopsmith on a GFCI circuit? If so, is tripping a problem? While on the subject, is anybody running their dust collector on a GFCI circuit? How does that work.
I read a lot of situations where people have equipment with large motors and are having problems tripping a GFCI regularly
RFGuy
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Re: GFCI protected circuits

Post by RFGuy »

My Mark V isn't on GFCI but my dust collector (ShopVac™) is on GFCI. No problems with it myself, but have had some issues in the past with GFCI and other types of equipment. Also have heard of others having GFCI problems with their shop equipment. I haven't seen anyone adequately explain why this is, so if anyone has insights I'd love to hear them. I know the GFCI is looking for small current differences between the hot and neutral or leakage to ground. Older equipment tends to not be double-insulated construction and/or have inadequate grounding that can cause a GFCI to trip sometimes. Some GFCI's just seem to be more sensitive than others. Also I have seen brand new GFCI receptacles act up when installed while others are fine (quality seems to vary a lot). When replacing, I always try to find hospital grade GFCI's instead of the standard ones though they are more expensive. I have never had strange issues with a hospital grade GFCI, so I am wondering if they would "fix" any GFCI trip issues with shop equipment. Just a thought.
📶RF Guy

Mark V 520 (Bought New '98) | 4" jointer | 6" beltsander | 12" planer | bandsaw | router table | speed reducer | univ. tool rest
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paulrussell
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Re: GFCI protected circuits

Post by paulrussell »

PowerPro on a 20A GFCI and DC-3300 on a 15A GFCI with no issues.
AEA
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Re: GFCI protected circuits

Post by AEA »

Garys,
yep, that would be me.
Sometimes if I don't turn the speed dial down and the shopvac/seperater is on, it will trip.
I've had it trip when I had to rip a pressure treated 2x6. I used a blade that was pretty well shot anyway because I didn't want to use a good one. It bogged down and blew the breaker. May have blown any under those situations.
My GFCIs seem inconsistent. No issues at all sometimes and then... well.

When I add circuits, I won't be installing GFCI breakers again.
AEA
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Re: GFCI protected circuits

Post by AEA »

I'm running 20A GFCIs and this happens to me on different circuits, so I can't just blame one breaker.

By the way paulrussell has the best icon, avatar, symbol, or what ever. (except now I can't get the tune out of my head)
DLB
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Re: GFCI protected circuits

Post by DLB »

I run my conventional 520 and DC-3300 on GFCI along with various other tools, including high-amp planer, no issues. I run my PowerPro on an isolated circuit that is not GFCI. I kind of just took their word for the idea that the PowerPro would probably trip it and didn't actually test. The paper that came with my PowerPro asserted that it would not trip if the GFCI was a CB instead of the outlet and downstream outlet setup that seems more common. I'm not sure why that would even make sense, but they must have tested it. From what I've read the thresholds are the same unless you cheat and put the wrong classification of breaker in.

I don't fully understand the GFCI requirement or how it relates to my garage shop. General rule is that garages must be GFCI. But I have a 230 VAC that is not GFCI and a 115 'washing machine' (currently PowerPro) 20 A 'dedicated' circuit that is also not GFCI. Either mine aren't right or there are exceptions. Which I'm happy with, I don't think metal equipment with a proper ground is a ground fault safety threat to the operator under a plausible failure mode.

- David
sehast
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Re: GFCI protected circuits

Post by sehast »

My Shopsmith worked fine on a GFCI until I upgraded to PowerPro. Never could get it to work so I now use a 220v circuit since I have it in my shop. Just easier than replacing the GFCI.
RFGuy
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Re: GFCI protected circuits

Post by RFGuy »

DLB wrote: Thu Apr 01, 2021 5:51 pm The paper that came with my PowerPro asserted that it would not trip if the GFCI was a CB instead of the outlet and downstream outlet setup that seems more common. I'm not sure why that would even make sense, but they must have tested it. From what I've read the thresholds are the same unless you cheat and put the wrong classification of breaker in.

- David
I have nothing concrete to go on here (other than my understanding as an engineer and my own intuition), but....Those GFCI CB are very expensive and I suspect much better built and engineered than the GFCI receptacles. In my experience the standard GFCI receptacles are poorly made and vary quite a bit. My neighbor had a GFCI go out in a kids bathroom. Keep in mind this gets HEAVY use with 1500W hairdryers so it literally burned up in only a few years of use. He went and replaced it and the brand new replacement kept tripping in use. I came and checked it out for him and there was nothing wrong with the wiring...it was just a bad GFCI right out of the box. Bought a new hospital grade GFCI and replaced it and no problems after this. Just one example, but I have had others like this. It would be interesting if someone has an issue with a GFCI receptacle with a PowerPro to have them try it with a hospital grade GFCI outlet to see if it fixes it. I would be curious to know if my theory is correct. GFCI CB are even more stout and better engineered/built so I suspect they are the ultimate fix for PowerPro tripping issues on GFCI.
📶RF Guy

Mark V 520 (Bought New '98) | 4" jointer | 6" beltsander | 12" planer | bandsaw | router table | speed reducer | univ. tool rest
Porter Cable 12" Compound Miter Saw | Rikon 8" Low Speed Bench Grinder w/CBN wheels | Jessem Clear-Cut TS™ Stock Guides
Festool (Emerald): DF 500 Q | RO 150 FEQ | OF 1400 EQ | TS 55 REQ | CT 26 E
DC3300 | Shopvac w/ClearVue CV06 Mini Cyclone | JDS AirTech 2000 | Sundstrom PAPR | Dylos DC1100 Pro particulate monitor
Mike907
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Re: GFCI protected circuits

Post by Mike907 »

I didn't have any problems with the PowerPro on my GFCi outlet, but when I got a Jet midi-lathe with a variable speed DC motor, it would trip the breaker every time. I purchased and installed a hospital grade GFCI outlet and that cured the problem.

Mike
lahola1
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Re: GFCI protected circuits

Post by lahola1 »

We had an apartment 4 plex where we replaced the 110v outlet in the laundry room w/ GFI to get it up to code(replaced w/a midpriced Menards GFI; not the cheapest one). The washer continually tripped the GFI. Replaced w/ another;I think the same price range; still tripped. Called in an electrician. He replaced it a name brand higher priced one and it worked with no problem after that. So I will buy a quality GFI from now on and save myself alot of headaches in the future.
SS Mark VII(sn 405025), SSband saw, SS 4" jointer, SS Mark V 1980,
Smithy SuperShop 720, Craftsman RAS, Ridgid TS2412 Table Saw,
Delta 12" planer
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