Grounding probe or No grounding probe
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Randy Holmes-Farley
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Yes to both, but it may not have any effect on your measurements if that is induced voltage, unless you measure right next to the ground.
Randy Holmes-Farley
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Can you trace it to a particular device?
Rob Top1
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If I could link in threads using my phone I would post some that are out there on the subject. In the wow I shocked my self one I shared a story how I believe gig saved my life in my opinion.
Water+salt+electricity= a serious need for safety
Water+salt+electricity= a serious need for safety
maroun.c
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Yes to both as I believe a GFCI is not that effective without a grounding probe.
Thunderfan
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Gfci and grounding probe are not related at all.
maroun.c
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As far as I know and I could be wrong, if you have electricity leaking in a non probed tank GFCI will not trip. The moment you place ur hand in the tank you become the probe and the electricity goes through you into the ground which causes the GFCI to trip. I'd rather have a grounding probe that will cause the GFCI to trip.
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Thunderfan
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Gfci senses current between the hot and neutral. The ground has nothing to do with it.
Dcmatranga
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I had tested my tank one day and had surprisingly found I had about 32v running through the tank. Randy said an important term - induced voltage - some automatically think that is it from damaged equipment, if it was - and you did have it connected to a GFI protected source, it indeed would trip as there would be a measurable difference between the hot and grounded conductor. The GFi measures that. Stray voltage is also often induced by motors such as pumps/powerheads and heaters as well. I had found this voltage when most of my equipment was new so I didn't thing the five contributing factors were all defective at once (2 200 watt nep therm heaters, 1 1100gph return pump, 1 sicce 200gph pump for my protein skimmer and 1 small pump for my phosban reactor). When I started unplugging all of my equipment, the voltage dropped. Each heater was reading 11v when tested individually, motors varied. I added a grounding probe, induced stray voltage went a way - more importantly, my fish and corals seem less stressed.
maroun.c
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For there to be a difference the current has to go somewhere or else its just circulating in the tank without killing fish(Bird on electrical wire), and possible can cause SPS or fish issues. and you'll feel it when you reach in the tank and become the way to the ground.
One additional advantage is that a properly grounded tank will not cause you to feel those annoying tiny electrical zips when you reach in the tank with an open wound on your hand. So i don't see any inconvenience to have a probe.
Randy Holmes-Farley
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Well, yes and no.
If you have a live wire exposed in the tank, the GFCI will only trip if there is a path to ground which takes some electricity away from the neutral of the GFCI. If not, the tank stays hot until something provides a path to ground.
That path might be you, if you touch the tank. I'd rather have that path be the ground probe as soon as there is an exposed hot wire, not days later when I stick my hand into the tank.
Windy
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Randy,
You are right in that the ground probe does not guarantee your safety. I don't use ground probes but if you must, the safe way is to mount them on a switch and turn them off when you are in the tank. That way you get the supposed benefits but you are not grounded when you are in the water and touch your light that is shorted.
You are right in that the ground probe does not guarantee your safety. I don't use ground probes but if you must, the safe way is to mount them on a switch and turn them off when you are in the tank. That way you get the supposed benefits but you are not grounded when you are in the water and touch your light that is shorted.
Randy Holmes-Farley
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Randy Holmes-Farley
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Most hobby heaters are not, but I do not know about that specific one.
How many prongs on the plug?
ca1ore
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I always stand on one of those live aquaria styrofoam shipping box lids when putting my hand into my sump.
gcrawford
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GFCIs and ground probes work together. Here's a test that proves it... Connect a power cord with hot and neutral to two probes and pierce them into a pickle. Plug this into a standard GFCI receptacle. The pickle will sizzle and actually light up and the GFCI will not trip. Now run the same test with a ground probe plugged into the GFCI and probe pierced into the pickle. The GFCI trips instantly. I saw this at a reef club meeting. Also, do not hold the pickle during the test!
Dcmatranga
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This thread is interesting to me - I'm an electrician by trade and electrical theory has always been of interest to me. Ground probes and safety are kind of tricky words to use in the same sentence. From my experience - a ground probe should only be used to correct an induced stray voltage issue (fairly common). While induced voltage is measurable - it is not stray voltage from damaged equipment, or voltage leakage - which is measurable as well. That said, if you have induced stray voltage running through your tank, and don't have a ground probe it is likely to stress your livestock as it did mine. I troubleshot from a-z every which way you can think of to identify the root of this problem and come up with a solution for my situation.
Induced stray voltage is usually minimal, I found an average of 32v and wanted to see what would happen when I closed the circuit. I held my finger in the water and touched the yoke of the receptacle ensuring I was in direct contact with ground - felt nothing. (This was after verifying none of my equipment was leaking voltage, very important - as that could lead to injury). In that situation a ground probe has no effect on safety, but serves its purpose by giving the induced stray voltage a direct path to ground. In the case of stray voltage from damaged equipment - the stray voltage/current would be searching for the path of least resistance and if the ground probe is in place - it should trip your over current protection device or circuit breaker given the water or path to ground is conductive enough. A GFCI adds a piece of mind by increasing the level of sensitivity of opening a circuit and cutting power by measuring the difference between the hot and grounded conductor or your neutral, as it's ultimately bonded at the main panel. Your typical 15Amp or 20Amp circuit breaker would open or trip when the current exceeded those ratings. All it takes for a GFCI to trip is a difference of 4-6 mA which is a very small amount of current when compared - this was introduced in the National Electric Code back in the 70's for 120v circuits namely around water. A bird on an electrical wire is a tough analogy as there is no contact to ground - in this case, water can be conductive - namely saltwater due to the elements. Just from my experience...
Induced stray voltage is usually minimal, I found an average of 32v and wanted to see what would happen when I closed the circuit. I held my finger in the water and touched the yoke of the receptacle ensuring I was in direct contact with ground - felt nothing. (This was after verifying none of my equipment was leaking voltage, very important - as that could lead to injury). In that situation a ground probe has no effect on safety, but serves its purpose by giving the induced stray voltage a direct path to ground. In the case of stray voltage from damaged equipment - the stray voltage/current would be searching for the path of least resistance and if the ground probe is in place - it should trip your over current protection device or circuit breaker given the water or path to ground is conductive enough. A GFCI adds a piece of mind by increasing the level of sensitivity of opening a circuit and cutting power by measuring the difference between the hot and grounded conductor or your neutral, as it's ultimately bonded at the main panel. Your typical 15Amp or 20Amp circuit breaker would open or trip when the current exceeded those ratings. All it takes for a GFCI to trip is a difference of 4-6 mA which is a very small amount of current when compared - this was introduced in the National Electric Code back in the 70's for 120v circuits namely around water. A bird on an electrical wire is a tough analogy as there is no contact to ground - in this case, water can be conductive - namely saltwater due to the elements. Just from my experience...
