GFI Circuit breakers

so no type of aquarium light falling into the water while your arm is under will be stopped of electricity by a GFCI? it's the light that i was mainly worried about... it's not like your return pump is going to kill you...

?
 
the good thing is that secondary side of the lighting isn't grounded anymore. anyway, GFI would only help with lights if you dropped the ballast into the tank.


yes, your return pump is the highest % of what could kill you. they leak around the epoxy seals, or the impeller housing cracks and leaks tankwater right into the copper wires or motor windings.
 
I agree that GFI should be used, but chances of life threatening incident is pretty remote, unless you have one hand in the water and your other hand is holding a metal bucket or something.... there is almost zero path to ground to complete the circuit.
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I don't know about that statement. I have been a construction electrician in Manhattan for almost 40 years and I believe I have been sufficiently shocked to be an expert on shocks.
Before GFI's our powerheads were not submersible, they hung on the side of the tank and they were not really designed for saltwater. The salt would creep up the sides of the thing making a great path for electricity to enter the tank. You could always feel it when you put your hand in the water but you would get the shock of your life when you touched the light (which were metal) or a piece of BX. I almost broke the glass once when I got shocked like that and instinctively pulled out my hand, only my hand tried to come out straight through the glass instead of out the top. If you feel like you don't want all the aquarium devices on one GFI breaker then use receptacles. You can put ten of them on a circuit. Just don't wire them together. Thats what I do.
After you get a shock that almost kills you by messing up your heart beat you will never put your hand in there without a GFI. As to a light falling in with your hand in there, that also happened to me. If the light fixture is not grounded and there is no ground probe in the water, the GFI will not trip and depending on a few situations, the current may pass through the water for quite a while before the breaker trips off. The light may even stay lit underwater for a few seconds. If your hand is in there, it will wake you up or permanently keep you asleep. :eek1:
How do you think Waterkeeper's hair got that way ? Thats really his picture
Have a great day.
Paul:dance:
 
Paul,

That jolt that got my hair wasn't from the household currrent but that darn Torpedo Ray I once had in my tank. I have since plugged him into a GFI. :D
 
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A transformer doesn't necessarily prevent a GFI from working. I have the charred socket and tripped GFI to prove it.
 
A transformer doesn't necessarily prevent a GFI from working. I have the charred socket and tripped GFI to prove it.
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A GFI doesent usually work through a transformer. In other words if you wire a 12 volt underwater pond light and it shorts out, the GFI probably will not trip. It depends on the transformer. Here in NY we have a code that a pond should be wired with an isolation transformer. I have done this and the GFI will not work. We built a new building on Fifth Ave with a pond in the entrance that circled the entire lobby. One light flooded and the entire wiring system to all the lights melted beyond recognition. The breakers did not even trip. An isolation transformer does exactly that, it isolates the low voltage circuit from the high voltage circuit thereby nullifying the GFI which measures corrent returning through ground.
Waterkeeper was it an AC ray or a DC one :confused:
 
I think it depends on how the transformer shorts. If the primary side, that is on line current, shorts to ground it should trip the GFI. On the other hand, the secondary is running on induction currents and a short to ground would not trip the GFI as the secondary is isolated from the line voltage.

I hope all you Newbies are following this!!!

:D
 
<a href=showthread.php?s=&postid=9559749#post9559749 target=_blank>Originally posted</a> by WaterKeeper


I hope all you Newbies are following this!!!

:D
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read every line and am as lost as when I started! :D
 
Is a ballast an isolation transformer ? No. Reason is the neutral of the line for a ballast transformer wires to the secondary neutral of a the ballast. Therefore any difference in current higher than 5-30 milliamp depending on the GFI would trip the GFI.According to NEC (different from the New York City Code) A Transformer has to be fused at the primary and the secondary in order to prevent problems such as the one paul B mentioned.
 
0 Agios Unless a distribution transformer, the secondary is not grounded (here).

if you short the output of a ballast in water, it won't trip a GFI unless the socket/reflector/fixture is grounded like PaulB said.
 
<a href=showthread.php?s=&postid=9560317#post9560317 target=_blank>Originally posted</a> by Icefire
0 Agios Unless a distribution transformer, the secondary is not grounded (here).

if you short the output of a ballast in water, it won't trip a GFI unless the socket/reflector/fixture is grounded like PaulB said.
Click to expand...

GFIs trip by sensing a current difference in their neutral. If theirs no ground probe in the watter not only the GFI wont trip but you can have a 120 volt "floating" tank and not know it till you have one hand in watter and the other is some kind of ground. Fish will probably survive this due to the no potential difference. A grounding probe installed will either trip the circuit breaker, GFI, or the least send fault current to ground. Thanks for the work.
 
<a href=showthread.php?s=&postid=9560317#post9560317 target=_blank>Originally posted</a> by Icefire
if you short the output of a ballast in water, it won't trip a GFI unless the socket/reflector/fixture is grounded like PaulB said.
Click to expand...
I agree that the wiring the outputs of a ballast together, either directly or through saltwater, won't trip a GFI, but that's true for every device, transformer or not, assuming there's no ground probe present. Other than that issue, my ballast definitely tripped the GFI, and of course the reflector, etc, were grounded, as I value my life and home.
 
<a href=showthread.php?s=&postid=9580339#post9580339 target=_blank>Originally posted</a> by IMAGINEER
this is exaclty why the battery back-up was decided against !!!!!
Click to expand...
you should have a continues ground even with a battery backup.
 
If your wiring looks like this..........don't expect a GFI to work.
P1010042.jpg
 
I use a battery backup with GFIs. You do have to put the GFI between the device and the battery backup, but otherwise the two are fine together.
 
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