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 Originally Posted by Jeffrey A. Steinberg
I thought that was against the national "standard" electrical code. I tried to do that and the building inspector told me "no way."
--Jeffrey
There's also a limit on how far an outlet can be from the GFI device, either breaker or outlet, and still have the GFI device function properly.
Keep in mind that a GFI device is not a guarantee that you won't be electrocuted. In a previous lifetime in an industry full of electricity and water, each time I entered the building I repeated an industry saying: electricity + water = death.
Charley
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 Originally Posted by c.d.ewen
There's also a limit on how far an outlet can be from the GFI device, either breaker or outlet, and still have the GFI device function properly.
Keep in mind that a GFI device is not a guarantee that you won't be electrocuted. In a previous lifetime in an industry full of electricity and water, each time I entered the building I repeated an industry saying: electricity + water = death.
Charley
Are you sure of that? I don't know you and you may be an electrician in which case I'll defer to you. However, the way a GFI device works is be detecting a difference in current between the hot wire and the neutral wire - if the currents are different, then some current is finding an alternate way to ground - i.e. through you. I don't see how a long wire is going to affect this - even if it adds resistance, the resistance will affect the current in each wire equally.
You are correct a GFI doesn't guarantee you won't be electrocuted. It just insures you won't be electrocuted for more than a fraction of a second.
Dan
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 Originally Posted by Jeffrey A. Steinberg
I thought that was against the national "standard" electrical code. I tried to do that and the building inspector told me "no way."
--Jeffrey
Actually, the national electrical code does allow the use of GFCIs in feeder breakers. Practically, however, it makes a lot more sense to install them in receptacles out on the circuit. And I think the receptacle-based units are less expensive that the version built into feeder breakers.
That said, the local jurisdiction always has the right to accept the NEC in its entirety and/or to supplement it with local requirements.
No where it is written that electrical inspectors actually have to be knowledgeable. But they do have the last word.
Modern receptacle-based GFCIs are designed to protect against problems on anything plugged into themselves, and may installed in a way that extends that protection to receptacles that are further downstream on the feeder. So if the only GFCI receptacles that you can find have LEDs, the simple solution is to plan for an additional receptacle OUTSIDE the darkroom (you can always use additional receptacles!), put the LED-GFCI there, and then extend the circuit to pick up the receptacles in the darkroom.
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The code also states that any outlets downstream from a GFI device must be clearly marked. This is because there are devices which won't work properly in a GFI outlet - notably a defibrillator will trip the circuit off.
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 Originally Posted by c.d.ewen
There's also a limit on how far an outlet can be from the GFI device, either breaker or outlet, and still have the GFI device function properly.
Keep in mind that a GFI device is not a guarantee that you won't be electrocuted. In a previous lifetime in an industry full of electricity and water, each time I entered the building I repeated an industry saying: electricity + water = death.
Charley
Actually, the traditional problem with GFCIs and circuit length goes back to the days when the only GFCIs available were incorporated into feeder breakers. In addition to providing a differential leakage current detection function, they also included the ability to detect if the neutral wire was grounded. That algorithm involved superimposing a high frequency voltage between neutral and ground and looking for current flow in the outgoing neutral. (You could actually hear the breakers humming at that high frequency.) The problem was that if the circuit was too long, the accumulated distributed capacitance would cause enough of a current flow to trigger the high-frequency current level detector and give a false trip.
I knew one of the people who was involved in the early development of GFCI technology, and he used to talk about how they would test prototypes on themselves. Made for interesting stories, but better him than me. I tend to agree with Charley that while I have GFCIs installed in our house, its always better to avoid those situations that might test their functionality.
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 Originally Posted by dslater
Are you sure of that? I don't know you and you may be an electrician in which case I'll defer to you. However, the way a GFI device works is be detecting a difference in current between the hot wire and the neutral wire - if the currents are different, then some current is finding an alternate way to ground - i.e. through you. I don't see how a long wire is going to affect this - even if it adds resistance, the resistance will affect the current in each wire equally.
You are correct a GFI doesn't guarantee you won't be electrocuted. It just insures you won't be electrocuted for more than a fraction of a second.
Dan
Dan:
IIRC, the distance limit (I remember 100 ft) is in the Leviton installation instructions. It may just be a manufacturer's CYA - a longer pull means more appliances, more chances for leakage, and a better chance the part will be returned as defective because it kicked when 'nothing's turned on'.
Regarding the life-saving guarantee of GFI, in the unusual but plausible case of finding yourself in contact with both hot and neutral legs, but insulated from ground, how does the GFI device distinguish you from a toaster?
I approach both fire and electricity with the assumption that either, given the chance, will try and kill me.
Charley
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Hmmm, I have a GFI that keeps tripping. It goes for nearly a year with no problem, then begins tripping every few hours - or days. It just went today for the first time in over a year, and cut off power to half of the darkroom. A reset and another trip later and I was scratching my head. Third reset and things are ok.
Oh, the wet side is on one GFI and the dry side is on another.
Any thoughts?
PE
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For the slope browed knuckle draggers in the crowd (and concerning electricity I'm at the front of the line) I found a simple solution today. Noma makes a 6' long GFCI power bar with four outlets on it...$26.00 CND at Canadian Tire.
Murray
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Note to self: Turn your negatives into positives.
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 Originally Posted by Photo Engineer
Hmmm, I have a GFI that keeps tripping. It goes for nearly a year with no problem, then begins tripping every few hours - or days. It just went today for the first time in over a year, and cut off power to half of the darkroom. A reset and another trip later and I was scratching my head. Third reset and things are ok.
Oh, the wet side is on one GFI and the dry side is on another.
Any thoughts?
PE
Hi, Ron:
Was it raining?
Confounded things are a mystery sometimes. I have one that won't let me put a lightswitch at the far end.
Charley
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Ron
Are the 2 GFCI's on the same circuit? More than 1 per breaker can sometimes cause problems.
Richard
Why are there no speaker jacks on a stereo camera?
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