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Joined: Mar 2007
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I dunno, Ghost. It's tough enough getting the humans to wear PPE, but cats? Maybe if they're made in camo that cats can use to hunt mice and birds.
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Joined: Jan 2003
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In the example above, where the light fell in while a person was trying to open the top, consider the likely reaction of a person in that situation. It is likely that he would grab for the light to remove it quickly. Now, a person is in contact with the metal hood of the light and/or the water of the tank. Depending on what else that person is in contact with, you now have a fault path. Brian in contact with what? What in that room is both grounded and within reach? But I was really talking about the GFCI helping the fish. I suspect the 5 ma that humans can handle is a little tough on a gold fish or the cat.
Bob Badger Construction & Maintenance Electrician Massachusetts
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Joined: Jun 2005
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I agree with Brian P because for a GFCI to trip it must sense current "leaking" from it's normal path back to the source. If the lamps falls in the drink, then current will flow through the water and lamp and eventually through any person unfortunate enough to take it out of the water. GFCI protection would avoid this.
Great discussion.
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Joined: Jul 2004
Posts: 787
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"I have to ask this, assuming the cord to the lamps are two wire how would a GFCI help?"
Perhaps a ground path is provided by the pump and filter, or the air bubbler? Perhaps if the wall and floor got splashed, there was enough leakage current thru the metal studs, or damp plaster, damp wood, or something else.
How long must the current flow before the trip threshold is reached? Would capacitance charging of the floor, wall and cat, be enough to trip the GFI?
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Joined: Feb 2007
Posts: 65
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Brian in contact with what?
What in that room is both grounded and within reach?
Without seeing the room, I don't know. One possibility is a metal stand for the aquarium with a power strip (with a metal case) sitting on it, plugged into a grounded outlet. (A power strip isn't that unlikely, since a basic setup (light, air pump, and heater) requires three cords.) Possibly through the floor, depending on footwear, flooring, dampness, etc. I don't know about the fish. How much current would go through the fish and how much would go around it? Better designs of aquarium lights would help (and there probably are some better ones available). Make it so it fits more securely on the top. A cat shouldn't be able to knock it off.
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Joined: Jun 2005
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Would the current flowing through the water (and fish) be considered current leakage?
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Joined: Jan 2005
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The GFI would not see current that went out the hot and returned through the neutral. That would look like any other load.
If there's one thing the trade has taught me, though ... try as you might, there ALWAYS seems to be a ground path somewhere. I've lost count of the 'tingles' I've had, when I thought I wasn't touching anything conductive.
At maybe $12, I figure a GFCI receptacle is cheap additional protection for the aquarium. Mine certainly has one ... and my house is two-wire (no ground).
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Joined: Jan 2005
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It might not not be in time to save Fluffy or keep from making 20 gallons of Chowder, but shouldn't the CB trip at some point?
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Joined: Feb 2003
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It might not not be in time to save Fluffy or keep from making 20 gallons of Chowder, but shouldn't the CB trip at some point? Unforetally not always the case because if the lumiaire do drop in the water and if the tank is fresh water it may not trip the breaker at all unless it have salt water then it have slightly more chance to trip the breaker depending how " condtiveity " of the water itself
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)
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HCE727
Delaware County, PA, USA
Posts: 187
Joined: November 2005
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