- Location
- Massachusetts
There are a lot of perfectly safe devices out there that routinely trip GFCIs.
Can you name a few?
If they leak enough current to trip a GFCI I would say they are only safe with an intact EGC.
There are a lot of perfectly safe devices out there that routinely trip GFCIs.
Can you name a few?
If they leak enough current to trip a GFCI I would say they are only safe with an intact EGC.
They shouldn't cause the GFCI to trip unless you had a bunch of them. The UL standard that permited those devices to use the EGC as a grounded conductor for the electronics said the maximum permitted current on the EGC from a single device was 0.5mA or 10% of the GFCI trip point.I have seen oc sensors trip gfi's due to their normal design leakage, but this was due to bathroom lights feed from the load side of the gfi. Not that common of a problem though. Just a design issue.
gfi protection is required in garages, exception receptacles that are not readily accesible?wouldnt this make it so the garage door opener plug dosnt have to be gfiI was correcting electrical violations in an older home in Livonia, Michigan, and the inspector wanted GFI's in two locations that I think are totally absurd.
1) Furnace condensate pump outlet. So, what happens if the GFI trips for whatever reason, and the air conditioner happens to be running in the middle of summer (or the high-efficiency furnace in winter)? The condensate pump won't go on, and there will be a puddle of water all over the floor, possibly damaging things in the basement.
2) Garage door opener. If the GFI outlet that feeds it trips for whatever reason, the owners arriving home will not be able to open the garage door, and they won't be able to get into the house.
Why are they requiring GFI's in these places? These are about as dumb as having a GFI for the refrigerator or freezer.
Those exceptions last appeared in the 2005 code.gfi protection is required in garages, exception receptacles that are not readily accesible?wouldnt this make it so the garage door opener plug dosnt have to be gfi
gfi protection is required in garages, exception receptacles that are not readily accesible?wouldnt this make it so the garage door opener plug dosnt have to be gfi
which would make them safe.
They shouldn't cause the GFCI to trip unless you had a bunch of them. The UL standard that permited those devices to use the EGC as a grounded conductor for the electronics said the maximum permitted current on the EGC from a single device was 0.5mA or 10% of the GFCI trip point.
Yes, but when you combine that with long home runs to a gfi breaker, fart fan, and a light, sometimes it's just enough to push it over the edge. What do you tell the customer when it starts tripping after the sensor was installed? As I said, not a frequent problem, but a problem all the same.
Why do those items contribute to tripping a GFCI? Long home run might but it usually takes something like 100 foot home run before you start to have troubles. If you have a really big home hopefully there are multiple panels strategically placed to make some of the home runs a little shorter. If the fan or light is causing trouble there is something wrong with them - or anything on the load side of the GFCI.
In commercial buildings home runs well over 100 feet is frequently done, especially the big box stores. The blue box usually has panels in all four corners, as where the orange has them only in the front and back. The warehouse clubs are the same way, they usually have them in front or back, but not in the corners. Most of these stores put oc sensors in the restrooms, but usually it's only the small employee restrooms that have the lights and fan on the same circuit. The other restrooms have 277 volt lighting which is on a non gfi protected circuit.
The only thing that requires GFCI protection in these rooms is 15 or 20 amp 125 volt receptacles. If you want to GFCI protect the entire circuit including the lighting there is nothing wrong with that, but do you want a tripped GFCI to cause the lights to go out?
Better design, IMO, would be to use GFCI receptacles - you would also solve potential issues of long home runs being a cause for GFCI tripping.
I agree with pretty much everything that has been said. I will add in the 2011 NEC the GFCI needs to be installed in a readily accessible location. So in the ceiling for the garage door opener is not acceptable - unless the ceiling is only 6 feet high. Behind the refrigerator is usually going to be considered not readily accessible.
You think the EC makes these design decisions at a job like that?
It's funny that on most construction sites 100' cords are used with not a whole lot of tripping. Granted there are those Einsteins that will lay cord caps in puddles and blame the tripping on the GFCI.
Roger
The 6' high part is an opinion since it's not defined by the NEC. Some of us can reach the test button on a GFCI device mounted on a 8' ceiling.