Using ground probes in aquariums

redfishbluefish

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Just to take this conversation a bit more....a grounding probe without GFCI is of no safety to your tank. Without the GFCI, and you now have a voltage leak, you now have current. And current is the killer. Without the GFCI, you'll never know when you're electrocuting your tank. A GFCI will detect this current and pop the breaker. It's the combination of the two that protects both you and your fish.

Now, with that said, I do not use a grounding probe. The reason is that I want to feel that tingle to know I have a voltage leak problem. If I were to use the recommended GFCI and grounding probe, my concern is that it will pop at the most inconvenient moment....when I'm on vacation....leaving my tank with no electricity. So I'll stick with the tingle....gosh, I've been zapped enough doing electrical work.....the tingle is nothing!

My recommendation is to do what you feel comfortable doing....nothing or GFCI with probe....whatever floats your boat.
 
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So you have the gfci outlets plugged into the apex then? Do amps still show up
Yup, still reads amps just like normal. To the apex, the GFCI receptacles are invisible. This was the absolute safest and most reliable system I could come up with. I use the MP40 powerheads not on GFCI since the motor are not in the tank. They are on a battery backup system but still wirelessly controlled by the Apex.
 
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Just to take this conversation a bit more....a grounding probe without GFCI is of no safety to your tank. Without the GFCI, and you now have a voltage leak, you now have current. And current is the killer. Without the GFCI, you'll never know when you're electrocuting your tank. A GFCI will detect this current and pop the breaker. It's the combination of the two that protects both you and your fish.

Now, with that said, I do not use a grounding probe. The reason is that I want to feel that tingle to know I have a voltage leak problem. If I were to use the recommended GFCI and grounding probe, my concern is that it will pop at the most inconvenient moment....when I'm on vacation....leaving my tank with no electricity. So I'll stick with the tingle....gosh, I've been zapped enough doing electrical work.....the tingle is nothing!

My recommendation is to do what you feel comfortable doing....nothing or GFCI with probe....whatever floats your boat.
I have to disagree with this. While a GFCI and grounding probe are the safest option, the grounding probe on its own does provide protection. A ground probe will make it impossible to develop a dangerous current in your tank. With a properly maintained ground probe installed, it is impossible to have a dangerous potential in your tank. (Kirchhoff's voltage law explains why if interested). A grounding probe along with most electrical faults will trip a breaker on overcurrent even if it isn't a GFCI for the vast majority of faults. A GFCI, by itself, will do nothing to protect your fish from induced voltages from your cables.
As for a GFCI tripping while on vacation, with proper design that situation can be mitigated as I believe I have done with my system.

With all that considered, I would much rather loose my entire tank than risk my or my families life by not providing an electrically safe system for an aquarium. If you are feeling a tingle from your system, you are very close to a potentially lethal amount of current. At that point, you are playing Russian Roulette.
 

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I have to disagree with this. While a GFCI and grounding probe are the safest option, the grounding probe on its own does provide protection. A ground probe will make it impossible to develop a dangerous current in your tank. With a properly maintained ground probe installed, it is impossible to have a dangerous potential in your tank. (Kirchhoff's voltage law explains why if interested). A grounding probe along with most electrical faults will trip a breaker on overcurrent even if it isn't a GFCI for the vast majority of faults. A GFCI, by itself, will do nothing to protect your fish from induced voltages from your cables.
As for a GFCI tripping while on vacation, with proper design that situation can be mitigated as I believe I have done with my system.

With all that considered, I would much rather loose my entire tank than risk my or my families life by not providing an electrically safe system for an aquarium. If you are feeling a tingle from your system, you are very close to a potentially lethal amount of current. At that point, you are playing Russian Roulette.

Couple of points of inaccuracies.
1. Electricity does not "always take the least path of resistance". It takes *all* paths available. If it only took the path of least resistance a parallel circuit could not exist.
2. Salt water is a dielectric (Google salt water capacitor), there is easily potential differences across various regions of the tank. A grounding probe is not a *hard* grounding point, and to suggest it will "drain" all current in the tank is likely wrong, and gives a false sense of security.
3. Because of the reasons above, and because we are generally dealing with 60Hz electricity, and varying magnetic fields, capacitance, etc., Kirchhoff's law isn't relevant.
4. There are far too many possible grounding (or lack of grounding) and energizing points to suggest that a grounding probe in a saltwater solution is going to provide the safety you imply.
5. Yes, induction will occur on any current carrying conductor, and a grounding probe won't eliminate them any more than waving a grounding probe near your pump would. If it could, all inductive devices (including the pumps) would cease to operate.

Can a grounding probe be useful? Perhaps, in conjunction with a fault clearing mechanism. By itself, it can provide a dangerous false sense of security. A ground indicator device would be far more useful.

My life, and the lives of my co-workers depends on proper grounding and bonding on a daily basis. This is why we take weeks long refresher courses just on grounding on a semi annual schedule. Never, ever, in the trade would anyone suggest a single ground in a dialectic with multiple energy inputs be considered as a life saving practice.

There, you got the counter-argument you were looking for :)
 

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I have to disagree with this. While a GFCI and grounding probe are the safest option, the grounding probe on its own does provide protection. A ground probe will make it impossible to develop a dangerous current in your tank. With a properly maintained ground probe installed, it is impossible to have a dangerous potential in your tank. (Kirchhoff's voltage law explains why if interested). A grounding probe along with most electrical faults will trip a breaker on overcurrent even if it isn't a GFCI for the vast majority of faults. A GFCI, by itself, will do nothing to protect your fish from induced voltages from your cables.
As for a GFCI tripping while on vacation, with proper design that situation can be mitigated as I believe I have done with my system.

With all that considered, I would much rather loose my entire tank than risk my or my families life by not providing an electrically safe system for an aquarium. If you are feeling a tingle from your system, you are very close to a potentially lethal amount of current. At that point, you are playing Russian Roulette.
Just wondering, do you unplug all your Appliances during an Thunder Storm, do you unplug your phones? Have you ever taken a Shower or Bath or done Dishes when there was a Thunder Storm? I mean technically we should be unplugging everything from our tanks during a Thunder Storm.
I myself do not run a Grounding probe and as in the last post if you don't not use a GFCI then do not bother. If you believe that just the probe will trip a breaker well check this out. He tends to ramble but it was interesting.

 
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Couple of points of inaccuracies.
1. Electricity does not "always take the least path of resistance". It takes *all* paths available. If it only took the path of least resistance a parallel circuit could not exist.
2. Salt water is a dielectric (Google salt water capacitor), there is easily potential differences across various regions of the tank. A grounding probe is not a *hard* grounding point, and to suggest it will "drain" all current in the tank is likely wrong, and gives a false sense of security.
3. Because of the reasons above, and because we are generally dealing with 60Hz electricity, and varying magnetic fields, capacitance, etc., Kirchhoff's law isn't relevant.
4. There are far too many possible grounding (or lack of grounding) and energizing points to suggest that a grounding probe in a saltwater solution is going to provide the safety you imply.
5. Yes, induction will occur on any current carrying conductor, and a grounding probe won't eliminate them any more than waving a grounding probe near your pump would. If it could, all inductive devices (including the pumps) would cease to operate.

Can a grounding probe be useful? Perhaps, in conjunction with a fault clearing mechanism. By itself, it can provide a dangerous false sense of security. A ground indicator device would be far more useful.

My life, and the lives of my co-workers depends on proper grounding and bonding on a daily basis. This is why we take weeks long refresher courses just on grounding on a semi annual schedule. Never, ever, in the trade would anyone suggest a single ground in a dialectic with multiple energy inputs be considered as a life saving practice.

There, you got the counter-argument you were looking for :)
1. While technically correct I didn't get into this in the interest of simplicity. A worst case value for for the resistance of a wet human body is 300 ohms. The resistance of a grounding plug is around o.1 ohms. This means almost 3000 times more current will flow through the ground probe during a fault than through a person. On a 20 amp breaker that limits continuous current through a person .006 amps in a worst case scenario. Most people wouldn't even get a tingle at that level.
2. Salt water is not a dielectric. By definition, a dielectric is a poor conductor of electricity. Salt water is an excellent conductor of electricity. I suggest you google a Leyden jar to learn more. In a salt water capacitor, the salt water is not the dielectric. Typically, the plastic or glass of the bottle is the dielectric. The water works to aid conductivity with the inner electrode.
3. Kirchhoff's law is always relevant. The sum of electrical voltages in a closed loop always adds to zero. With the low resistance to ground you can use this law to show exactly how much current you would need across the ground probe to achieve any dangerous level of voltage in your tank, regardless of possible parallel paths. It is much more current than your house can supply for more than an instant.
4. Just because a lineman can't hang a ground on every section of the conductor he is working on doesn't mean that it is worthless to hang grounds at all. We may not be able to "work between grounds" in a salt water tank but it is much better to have 1 ground than none.
5. A ground probe doesn't stop induction any more than a floor stops gravity. What a ground probe does is reduce the voltage in a tank to a safe level for the fish (induced voltages on a 120V system are not dangerous to people). I maintain an old Simpson voltmeter just because of this principle. Modern voltmeters are very high impedance devices. If you remove the power source to a device in an industrial setting it is very common for it to still read over 200VAC for a 480V system due to inductance. If you use an older Simpson voltmeter, it has a much lower impedance and will drain that voltage to ground if it is induced. If the voltage stays steady you know you didn't isolate the power correctly. In my tank, with the grounding probe removed, I see between 23V-27V. With the grounding probe installed, my voltage drops to under 400mV. My ground probe draws around 0.2 amps to accomplish this.

A grounding probe is very useful, and the circuit breaker(s) you feed your aquarium with is a fault clearing mechanism. Using it in conjunction with a GFCI is even better.

In the trade, a single ground connection on a conductor is a very common practice. I have already established that salt water is not a dielectric (insulator). Single point grounds are most certainly considered life saving practices.
 
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Just wondering, do you unplug all your Appliances during an Thunder Storm, do you unplug your phones? Have you ever taken a Shower or Bath or done Dishes when there was a Thunder Storm? I mean technically we should be unplugging everything from our tanks during a Thunder Storm.
I myself do not run a Grounding probe and as in the last post if you don't not use a GFCI then do not bother. If you believe that just the probe will trip a breaker well check this out. He tends to ramble but it was interesting.
Unfortunately, I cannot watch the video right now but I will do so when I can (probably tomorrow).

I do not unplug my appliances during a thunder storm, and I will take a bath during a thunder storm. Electrical code requires a houses electrical system to be bonded to earth using a grounding rod. This reduces the peak voltage if your house is struck by lightning. If your house uses metal water piping, those are also required to be bonded to your houses grounding rod. Since homes run fresh water, not salt water, the water isn't conductive enough to pose a hazard if run in insulated piping. This grounding rod works very well even though the feed to your house does not use a GFCI. Inserting a ground probe into your tank effectively extends the protection provided by your homes ground rod into your aquarium.
 
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This battle has been hashed out 100 of times on fish forums.
I have seen this hashed out many times. I have never seen a technically reasonable argument against the use of a ground probe other than the possibility of a temperature rise. That is why I felt it was important to address this in a new post.
 

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1. While technically correct I didn't get into this in the interest of simplicity. A worst case value for for the resistance of a wet human body is 300 ohms. The resistance of a grounding plug is around o.1 ohms. This means almost 3000 times more current will flow through the ground probe during a fault than through a person. On a 20 amp breaker that limits continuous current through a person .006 amps in a worst case scenario. Most people wouldn't even get a tingle at that level.
2. Salt water is not a dielectric. By definition, a dielectric is a poor conductor of electricity. Salt water is an excellent conductor of electricity. I suggest you google a Leyden jar to learn more. In a salt water capacitor, the salt water is not the dielectric. Typically, the plastic or glass of the bottle is the dielectric. The water works to aid conductivity with the inner electrode.
3. Kirchhoff's law is always relevant. The sum of electrical voltages in a closed loop always adds to zero. With the low resistance to ground you can use this law to show exactly how much current you would need across the ground probe to achieve any dangerous level of voltage in your tank, regardless of possible parallel paths. It is much more current than your house can supply for more than an instant.
4. Just because a lineman can't hang a ground on every section of the conductor he is working on doesn't mean that it is worthless to hang grounds at all. We may not be able to "work between grounds" in a salt water tank but it is much better to have 1 ground than none.
5. A ground probe doesn't stop induction any more than a floor stops gravity. What a ground probe does is reduce the voltage in a tank to a safe level for the fish (induced voltages on a 120V system are not dangerous to people). I maintain an old Simpson voltmeter just because of this principle. Modern voltmeters are very high impedance devices. If you remove the power source to a device in an industrial setting it is very common for it to still read over 200VAC for a 480V system due to inductance. If you use an older Simpson voltmeter, it has a much lower impedance and will drain that voltage to ground if it is induced. If the voltage stays steady you know you didn't isolate the power correctly. In my tank, with the grounding probe removed, I see between 23V-27V. With the grounding probe installed, my voltage drops to under 400mV. My ground probe draws around 0.2 amps to accomplish this.

A grounding probe is very useful, and the circuit breaker(s) you feed your aquarium with is a fault clearing mechanism. Using it in conjunction with a GFCI is even better.

In the trade, a single ground connection on a conductor is a very common practice. I have already established that salt water is not a dielectric (insulator). Single point grounds are most certainly considered life saving practices.

1. Unfortunately, sometimes in the interest of simplicity we miss some important nuances. While the grounding probe itself may measure 0.1 ohms across it's length, you may have a significant amount of saltwater between the voltage injection point, and the grounding point. If the ground probe is in my display tank for example, and my return pump is defective, and I reach into the sump, your simplified current calcs fall apart. Also, how many cycles does it take for a 20 amp breaker to trip, and how much current will a 20 amp breaker allow to flow in a fault condition before it trips? I'm sure you are aware fault currents can far exceed the protection continuous rating, and is somewhat irrelevant to the discussion, suffice to say they can be lethal with or without a grounding probe.

2. If we want to get into specific definitions then, saltwater is not an "excellent conductor of electricity", as far as conductors go, it's a rather poor one. Nor is it a particularly good insulator, in fact its properties are very close to the dividing line between the two. Perhaps some of the confusion lies in a misunderstanding of exactly how salt water "conducts" electricity. It doesn't work like a typical solid conductor pushing electrons (or holes) down the line, which is what most of your statements seem to be based on. Current is carried by free ions in the electrolytic solution (salt water), which is part of the reason why basic ohms law, kirchoff's current and voltage laws essentially break down, and are no longer "laws" applicable to what is happening when electrical potentials are applied to electrolyte solutions. 2(a) A Leyden jar is similar in construction to a salt water capacitor, but is not, as it can be constructed without salt water :) In a salt water capacitor, the dielectric medium includes both an electrolyte (salt water) + the jar wall. Ions in the solution move to the opposite charged electrode and become a double layer...it becomes much more effective at shielding the charge, and charge densities will be much higher.

3. Kirchoff's law(s) are not "always relevant", they are *only* relevant in, and wholly dependent on the lumped element model. Kirchoff's laws are a very simplified method to describe simple closed circuits models with the electric charge remaining constant. KCL is dependant on the assumption that current flows only in conductors, and that it immediately flows out the other end. Since salt water conducts by free ions and there are an infinite number and varying paths and charge densities, the lumped element model is not applicable, therefore the laws do not apply.

4. Lineman use EPZ (EquiPotential Zero..or grounding). This involves a far more complicated grounding scheme than a probe in a tank of electrolyte. If you want to put a ground grid in the bottom and sides of your tank, tie that to a potential equalizing mat for you to stand on, wear dielectric boots and class 0 gloves while working on your tank, after you have isolated the power to the tank, you can compare the two, otherwise there is zero comparison between the two methods. You realize the main reasons linesman hang grounds is to force the protections to work much faster should the line become energized, and to drain induced voltages that may be present and dangerous in the kV levels. It's their insulated equipment that protects them from being zapped, not the grounds.

5. Sure, a ground probe can drain some induced voltages in the tank, and as you said, induced voltages off a 120v system isn't really a concern.

Grounding is a complex topic on which experts in the field don't agree. Look at entire committees which are unable to come to agreements for codes and standards for grounding, or go on any forum discussing high voltage work, and watch guys who have been hanging grounds on high voltage systems for more than 30 years argue about practices and the like. We are never, ever, going to come to a consensus on a reef tank forum, and I knew that when I debated on responding to the thread. I responded only so that through discussion, people would realize that adding a ground probe to the tank can give a false sense of security that isn't there. I will agree, that on the whole, a grounding probe may add some safety in some situations. To rely on it with your life is foolhardy.

I would like to leave the participants of this thread with this, especially those that think I am wrong in my assessment of the safety afforded by a grounding probe;
Most codes require some sort of ground fault interrupter in bathrooms, pools, hot tubs etc.
If a grounding probe in an electrolytic solution ("un-pure" water such as in our tanks, our swimming pools, hot tubs, baths, etc) provided any real measure of life safety, it would be written into every electrical code as required equipment where people immerse body parts.
There are exactly Zero codes that I am aware of, that require a grounding probe in the water. Why is that?
 
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1) I have used a precision ohm meter on my aquarium. I read 0.04 ohms from the water in my DT to the ground receptacle beneath the one my ground plobe is plugged into. If you are getting .1 ohms just across your ground plug, it is faulty or you are measuring it with a low quality meter. If you electrical devices in your DT and your sump, I would recommend putting a ground probe in both. I have no electrical devices in my DT so one in my sump is adequate. As for how many cycles does it take for a breaker to trip? That depends. You are looking at the unrealistic scenario that a massive fault occurs while you have your hand in the tank. Even then, with a ground probe, you will be safe unless you really believe you can pull 800+ amps through your faulted power cord. On a 120V system this is mathematically impossible. With time current characteristics of breakers, it will still trip almost instantly at these levels.

2) Sea water is an excellent conductor. It has an average resistance of 0.2 ohms per meter. That is no where near dielectric levels. If you drained the oil out of a capacitor and filled it with sea water it will not function. I agree that the flow of electricity is different in water than it is through a solid conductor however for practical purposes such as a discussion on home aquariums that isn't relevant. A Leyden jar is the earliest form of a salt water capacitor. It doesn't require salt water, however the water does have to have enough impurities to conduct electricity. In a typical salt water capacitor an outer conductor is wrapped around a bottle as one conductive layer. The bottle itself is the dielectric. It is difficult to tightly wrap a conductive sheet to the inside of a bottle so salt water (or other dirty water) is used as the inside conductor. You then go on to discuss a salt water battery which is a completely different concept from a salt water capacitor.

3) Kirchhoff's laws always do apply. How to define the closed loop in a water system can become more difficult, but that does not invalidate the laws. If you hook up a power source, AC or DC, and connect it across an aquarium full of salt water, the sum of all voltages through the loop will always be zero. They do not call ohms law "ohms good idea" for a reason. It always applies.

4) I routinely both work, and supervise work, on 500kV systems. We work between grounds to reduce the possible voltage rise in the event that the line becomes energized. The requirement is that the grounds must be able to carry full fault current for the length of time it takes for a protective trip to occur. The fact that a protective trip may happen more quickly is only an added benefit. We also use them to eliminate induced voltages. Once a line is properly grounded we no longer wear any insulating equipment. We use bare hands and steel toed work boots and do this work where there is no ground grid. And no, the concepts between a ground probe and linemen safety grounds isn't nearly as different as you make it sound.

5) On this we agree. You cannot induce enough voltage at the 120V level to cause harm to a human. However, as you have also pointed out, voltage is not uniform throughout salt water. A marine fish cannot be shocked, but that doesn't mean that having small voltage differences across their body doesn't cause them issues.

Grounding is a complex topic however the disagreements tend to be based on nuances, not major philosophical differences. No lineman I have ever met would argue that he would rather not hang grounds. They only disagree on the PPE needed to hang them. I know of no place in the nation that doesn't have code requirements to connect your homes neutral line to ground.

It is a shame that we as reefers cannot come to a consensus on the use of ground probes. I think in the not too distant future the vast majority will use them. I see this as being like the seat belt argument. You can find the very rare occurrence where not wearing a seat belt may have saved someone. It would be foolish to completely rely on seat belts and airbags to save your life or give you a false sense of security while driving. This does not mean that wearing a seat belt or having air bags isn't a good idea.
To say a grounding probe isn't a good recommendation because it isn't required by a code is not a valid argument. By requiring GFCI in bathrooms and near pools, and requiring all electrical pool components to be grounded, there is little need for a grounding probe. There are many areas that are not properly addressed by code. Why aren't GFCI's required by code to be used on aquariums? It isn't because using them is not a good idea. Aquariums simply aren't covered.
 

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1) I have used a precision ohm meter on my aquarium. I read 0.04 ohms from the water in my DT to the ground receptacle beneath the one my ground plobe is plugged into. If you are getting .1 ohms just across your ground plug, it is faulty or you are measuring it with a low quality meter. If you electrical devices in your DT and your sump, I would recommend putting a ground probe in both. I have no electrical devices in my DT so one in my sump is adequate. As for how many cycles does it take for a breaker to trip? That depends. You are looking at the unrealistic scenario that a massive fault occurs while you have your hand in the tank. Even then, with a ground probe, you will be safe unless you really believe you can pull 800+ amps through your faulted power cord. On a 120V system this is mathematically impossible. With time current characteristics of breakers, it will still trip almost instantly at these levels.

2) Sea water is an excellent conductor. It has an average resistance of 0.2 ohms per meter. That is no where near dielectric levels. If you drained the oil out of a capacitor and filled it with sea water it will not function. I agree that the flow of electricity is different in water than it is through a solid conductor however for practical purposes such as a discussion on home aquariums that isn't relevant. A Leyden jar is the earliest form of a salt water capacitor. It doesn't require salt water, however the water does have to have enough impurities to conduct electricity. In a typical salt water capacitor an outer conductor is wrapped around a bottle as one conductive layer. The bottle itself is the dielectric. It is difficult to tightly wrap a conductive sheet to the inside of a bottle so salt water (or other dirty water) is used as the inside conductor. You then go on to discuss a salt water battery which is a completely different concept from a salt water capacitor.

3) Kirchhoff's laws always do apply. How to define the closed loop in a water system can become more difficult, but that does not invalidate the laws. If you hook up a power source, AC or DC, and connect it across an aquarium full of salt water, the sum of all voltages through the loop will always be zero. They do not call ohms law "ohms good idea" for a reason. It always applies.

4) I routinely both work, and supervise work, on 500kV systems. We work between grounds to reduce the possible voltage rise in the event that the line becomes energized. The requirement is that the grounds must be able to carry full fault current for the length of time it takes for a protective trip to occur. The fact that a protective trip may happen more quickly is only an added benefit. We also use them to eliminate induced voltages. Once a line is properly grounded we no longer wear any insulating equipment. We use bare hands and steel toed work boots and do this work where there is no ground grid. And no, the concepts between a ground probe and linemen safety grounds isn't nearly as different as you make it sound.

5) On this we agree. You cannot induce enough voltage at the 120V level to cause harm to a human. However, as you have also pointed out, voltage is not uniform throughout salt water. A marine fish cannot be shocked, but that doesn't mean that having small voltage differences across their body doesn't cause them issues.

Grounding is a complex topic however the disagreements tend to be based on nuances, not major philosophical differences. No lineman I have ever met would argue that he would rather not hang grounds. They only disagree on the PPE needed to hang them. I know of no place in the nation that doesn't have code requirements to connect your homes neutral line to ground.

It is a shame that we as reefers cannot come to a consensus on the use of ground probes. I think in the not too distant future the vast majority will use them. I see this as being like the seat belt argument. You can find the very rare occurrence where not wearing a seat belt may have saved someone. It would be foolish to completely rely on seat belts and airbags to save your life or give you a false sense of security while driving. This does not mean that wearing a seat belt or having air bags isn't a good idea.
To say a grounding probe isn't a good recommendation because it isn't required by a code is not a valid argument. By requiring GFCI in bathrooms and near pools, and requiring all electrical pool components to be grounded, there is little need for a grounding probe. There are many areas that are not properly addressed by code. Why aren't GFCI's required by code to be used on aquariums? It isn't because using them is not a good idea. Aquariums simply aren't covered.

It sounds like we worked in similar sectors, at one time I supervised, wrote and issued isolations for high voltage circuits (including 500kV) as part of my job. I also sat on a committee of 6 that wrote the criteria and governance for live work that will hopefully be rolled out soon across our province.
As for theory as to what happens electrically in our tanks, we are approaching it from two different levels, much like classical physics vs quantum physics...the rules in one world don't always apply to the other, and it appears there is nothing more to be gained from this conversation, as we are going to keep going around the same talking points.

I think the one thing we can agree on, is that in conjunction with a ground fault circuit interrupter, in some cases a ground probe will "help" a gfci work, where it otherwise wouldn't detect it.

In this day and age, I would never advise anyone to/or not do anything electrically that wasn't covered by some code, standard, or form of governance that specifically spelled out the criteria for doing so, and of course, advise them to have some qualified/certified individual install it for them in compliance with that standard. In your seatbelt analogy, I shudder to imagine someone losing their home/life to an electrical fire because of an inadequate grounding probe wire and no gfci
 

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Just wondering, do you unplug all your Appliances during an Thunder Storm, do you unplug your phones? Have you ever taken a Shower or Bath or done Dishes when there was a Thunder Storm? I mean technically we should be unplugging everything from our tanks during a Thunder Storm.
I myself do not run a Grounding probe and as in the last post if you don't not use a GFCI then do not bother. If you believe that just the probe will trip a breaker well check this out. He tends to ramble but it was interesting.



Thanks for sharing that video. Even with two ground probes the tank was still live.
He sums up at the end perfectly : "a ground probe is not a safety device"
 
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Brew12

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If you believe that just the probe will trip a breaker well check this out. He tends to ramble but it was interesting.

Thanks for sharing that video. Even with two ground probes the tank was still live.
He sums up at the end perfectly : "a ground probe is not a safety device"

I had a chance to watch the video last night. Other than his poor understanding of electricity, I found his test to be interesting. So, I went to work this morning in an attempt to reproduce his result.
The first thing he didn't understand is that his neutral wire in and of itself acts just like a ground probe. His neutral should be bonded to ground in his distribution panel. Regardless, this lack of knowledge doesn't really change his results, but it did make adding a ground probe redundant.

I filled a bucket with water from my DT and took I to work. I hooked it up to a test bench and made a similar setup to him except I used test leads, not a cut up cord. The leads were secured 6 inches apart on a insulated board. I turned on the 20 amp breaker and it tripped immediately. I checked my setup, didn't find anything wrong and closed in the breaker again. Once again, it tripped immediately. I switched my power supply to a 30 amp breaker and it also tripped immediately. These were the results I expected, but wanted to confirm via actual testing.
After giving it some thought, I figured out why his tests worked the way they did. I went back and watched the first part of the video again, and the early parts of his other videos. He always mentioned that there was water in the bucket. He never said it was salt water.
To verify this, I dumped my salt water, rinsed the bucket, and refilled it with tap water. Sure enough, I was able to close the breaker and had between 23V-30V in the bucket.
I would agree that a ground probe is completely worthless in a fresh water aquarium. His test prove that. As a reefer, he should have ran his test using salt water. It makes me wonder if that is why his comments are blocked on these videos.

People creating and posting videos like this, who obviously have no clue about electricity, contribute to all of the misinformation on this topic. Unfortunately, the average reefer will see these video's and be left with a wrong impression.
 
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It sounds like we worked in similar sectors, at one time I supervised, wrote and issued isolations for high voltage circuits (including 500kV) as part of my job. I also sat on a committee of 6 that wrote the criteria and governance for live work that will hopefully be rolled out soon across our province.
As for theory as to what happens electrically in our tanks, we are approaching it from two different levels, much like classical physics vs quantum physics...the rules in one world don't always apply to the other, and it appears there is nothing more to be gained from this conversation, as we are going to keep going around the same talking points.

I think the one thing we can agree on, is that in conjunction with a ground fault circuit interrupter, in some cases a ground probe will "help" a gfci work, where it otherwise wouldn't detect it.

In this day and age, I would never advise anyone to/or not do anything electrically that wasn't covered by some code, standard, or form of governance that specifically spelled out the criteria for doing so, and of course, advise them to have some qualified/certified individual install it for them in compliance with that standard. In your seatbelt analogy, I shudder to imagine someone losing their home/life to an electrical fire because of an inadequate grounding probe wire and no gfci
Just because people debate how gravity works does not mean the apple won't fall from the tree. Run the test like was done in the video yourself, using salt water. If your breaker doesn't trip I expect your cord will catch on fire.

There is no code anywhere in the US for plugging an aquarium, a computer, or a TV. I will not say people shouldn't use these devices because there isn't a code for them. I'm not sure where you live (since you said province) but in the US, all of our residential electrical codes are based on permanent or semi-permanent installations. We have codes for industrial and commercial facilities that cover some temporary installations, but they don't apply to residential. We have no codes for things you may bring into your home to use.
 

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I had a chance to watch the video last night. Other than his poor understanding of electricity, I found his test to be interesting. So, I went to work this morning in an attempt to reproduce his result.
The first thing he didn't understand is that his neutral wire in and of itself acts just like a ground probe. His neutral should be bonded to ground in his distribution panel. Regardless, this lack of knowledge doesn't really change his results, but it did make adding a ground probe redundant.

I filled a bucket with water from my DT and took I to work. I hooked it up to a test bench and made a similar setup to him except I used test leads, not a cut up cord. The leads were secured 6 inches apart on a insulated board. I turned on the 20 amp breaker and it tripped immediately. I checked my setup, didn't find anything wrong and closed in the breaker again. Once again, it tripped immediately. I switched my power supply to a 30 amp breaker and it also tripped immediately. These were the results I expected, but wanted to confirm via actual testing.
After giving it some thought, I figured out why his tests worked the way they did. I went back and watched the first part of the video again, and the early parts of his other videos. He always mentioned that there was water in the bucket. He never said it was salt water.
To verify this, I dumped my salt water, rinsed the bucket, and refilled it with tap water. Sure enough, I was able to close the breaker and had between 23V-30V in the bucket.
I would agree that a ground probe is completely worthless in a fresh water aquarium. His test prove that. As a reefer, he should have ran his test using salt water. It makes me wonder if that is why his comments are blocked on these videos.

People creating and posting videos like this, who obviously have no clue about electricity, contribute to all of the misinformation on this topic. Unfortunately, the average reefer will see these video's and be left with a wrong impression.

I don't know if it is obvious he has no clue about electricity or not, or whether he is aware the neutral is bonded to ground in residential wiring or not. It appears he was trying to bring some basic concepts down to a level that whomever he was having a discussion with could understand.

Your test, unfortunately, is no more conclusive than the other video. What you demonstrated was no need for a ground probe....create a short, and the in feed breaker trips, voila...what do I need a ground probe for? The only circumstance where I see a ground probe doing anything in regards to trying to limit "lethal to human" currents, is with a leaking voltage/current from the "hot", without a return path. Therefore you would need to simulate a situation where the tank is actually "hot", but not a complete circuit which trips the infeed breaker. Something along the lines of a 3 to 6 foot long non-conductive trough filled with seawater, and a potentiometer on the hot, allowing you to control the voltage/current so that you have measurable voltage and current flow in the solution, ground probe in the other end, and measure the voltage at various set points, and distances from the source with and without the ground probe.....does it keep the saltwater voltage low enough to not be of a concern? (And I hope everyone is aware, that without a ground fault interrupter, that means with a 20Amp circuit breaker, it can flow 20 amps continuous through the tank, to the ground probe, all day long without tripping, ground probe or not). What I suspect would happen is along the lines of the equivalent result of a variable center tap, the question is, what is the max voltage obtained with a ground probe in solution, and I suspect it would be well above 12 volts or so.
Obvious to me, this is an extremely dangerous test and potentially lethal to perform, and I would highly advise against anyone attempting this in real life, it's not worth the risk, not to mention all the off gassing of chlorine, hydrogen, oxygen and who know what else that would take place as you turned the tank into a huge electrolysis cell.
 

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I have seen this hashed out many times. I have never seen a technically reasonable argument against the use of a ground probe other than the possibility of a temperature rise. That is why I felt it was important to address this in a new post.

Threads like this is why I don't go on ground probe or GFCI threads any more. Have fun :D
(Master Electrician 40 years. Retired, Thank God)

 

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Just because people debate how gravity works does not mean the apple won't fall from the tree. Run the test like was done in the video yourself, using salt water. If your breaker doesn't trip I expect your cord will catch on fire.

There is no code anywhere in the US for plugging an aquarium, a computer, or a TV. I will not say people shouldn't use these devices because there isn't a code for them. I'm not sure where you live (since you said province) but in the US, all of our residential electrical codes are based on permanent or semi-permanent installations. We have codes for industrial and commercial facilities that cover some temporary installations, but they don't apply to residential. We have no codes for things you may bring into your home to use.

The consumer devices we buy have UL or CSA certification or the like, do these grounding probes come with a UL or similar "stamp"?

Re the gravity/apple falling example, unfortunately, we don't seem to be able to agree on even what I thought were basic concepts...from my viewpoint, yes, it is much like arguing if the apple would fall from the tree or not.
Take your continuted repeated statement, that seawater is a "very good conductor" of electricity, that to me is like a person repeatedly insisting a solution of 6.9 pH is a "strong" acid. A "very good conductor", is say, copper. 1.68 x 10 -8 p(ohm*meter) at 20 deg C A good insulator, like hard rubber is 1.0 x 10 +13. Seawater is about 2.0 x 10-1. That is pretty close to the neutral point between the two. Notice copper is 8 significant digits to the right, and rubber is 13 significant digits to the left...and seawater is only 1 significant digit to the right? In my book, that is very close to being in the middle between the two, and what I consider a "good conductor" (copper for example) is about 10 million times more conductive than seawater. Will an electrolytic solution like seawater conduct electricity with enough force (potential) applied? Yes, certainly. Is it a "good conductor"? Certainly not.

We seem to stumble into disagreement in virtually every paragraph, and what I fear, is what happens so often when communicating via forums, newsgroups, email, etc, is the tone of text can come across to the reader completely differently than the intent of the author, and it quickly devolves into something unproductive. I'm afraid we are so far apart on just the basics, there is no fruit to bear in continuing on. So on that note, thank you for the discussion, may your corals grow fast and colourful and multiply, and may your fish be fat and healthy, cheers!
 

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Just wanted to say thanks for posting! I don't use a grounding probe mostly because of the conflicting information about them....this was very helpful even if we didn't establish World Peace™ in the effort. :)
  • Didn't know about the requirement for a GFCI, but it makes perfect sense.
  • Didn't know multiple probes would be recommended for installations where there's equipment in every tank.
  • Didn't know current (or was it voltage) would vary inside of eddy currents....that is awesome! Water flow and current flow have some interesting parallels or similarities.
  • Didn't realize that the main catching point for most people (who maybe also didn't realize it) is the possibility of an unattended power outage caused by one power defect. Some kind of notification to the reef keeper would help, but with a power outage in effect, some planning and accommodation would be required.

@Paul B is that you in the photo!? Hahaha. :D:D (Or where'd you find that?)
 
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