Do you use a Ground Probe?

[RyanM]

Was wondering how many use a ground probe and why?

I asked a question about ground probes in another thread and was flamed for my comments on them. A short time later I was PM'ed by a fellow reefer and was given a link to read. What do you think?

This pole is not if you use a ground probe. The pole is would you use one after reading this.

Also let everyone know in a reply if you now use one or not.
This link confirms what I was saying.
http://avdil.gtri.gatech.edu/RCM/RCM/Aquarium/GroundingProbes.html

 

[RyanM]

link works now

 

[The_Boyz1]

Link doesn't work

 

[RyanM]

Its fixed

 

[engine]

I was thinking about getting one.......dont think I will after reading that

 

[SkiFletch]

I've always known this, but didn't know how to explain it. Bout time somebody figured it out and wrote it down in relatively understandable english

 

[RyanM]

I tryed to explain why I thought the way I did and got nothing but flack for it. Like you im glad someone explained it as well.

 

[SkiFletch]

Yeah, its hard to challenge something thats either commonplace or accepted

 

[RyanM]

LOL yea that is my problem, I tend to do that a bit to much.
Im hard headed for sure.

 

[Gary Majchrzak]

There's a bad trend for people to believe what they read on the internet as gospel. I really dislike articles that don't cite an author or source and I certainly wouldn't base an important decision on something like this.
The article in your link appears to be on someone's website, but it was copied from somewhere else (I've seen it before).
FWIW
I used to run a ground probe (for many years) but more recently I haven't (for the past two or three years).

 

[bjromaine]

I am not sure who wrote that article but there are a few items that are not entirely correct.....
First of all Voltage cannot Exist without Current....PERIOD, it is the law of electricity.....but it is not straight forward....
IF a voltage exists, a current potential exists, always. The current will not flow if there is no electrical path.
For all intense purposes water, including salt water is a very GOOD conductor of electricity....not perfect but very good.

It is NOT normal for any tank to have a voltage potential. This is an indication of malfunctioning equipment......There is nothing in your tank that produces electricity in a range that anyone would care about.....or for that matter, be able to measure.
If you have a voltage potential in your tank, i.e. a pump that has a bad seal, you have the potential for current to flow.....when a return path is provided. That path is very SELDOM provided by the same piece of equipment that is leaking voltage into the tank, if so, a short would exist which would short out the circuit.

The real skinny on ground probes is this.
YES they do provide a path for stray (and I hate that term) voltages to short to ground. Most likely if you have a piece of equipment that is shorting to the water, the fish will feel NO effects until a return path is provided. Without a return path, the potential current does not flow, even though it is there.

BUT, and here is the part that is more often not mentioned, IF you have the above situation and YOU or another person sticks their hand in the water AND they provide any path for current to flow, such as their feet are wet, they touch a grounded device (light a metal light canopy), etc, a path now exists from the malfunctioning device through the water, through YOU and to ground eventually.

THUS, if you do not use a ground probe, your fish may not be harmed if you have a malfunctioning device, BUT BUT BUT YOU or someone you love MAYBE either severely injured or ELECTROCUTED!!!!!!!!!!!!!!!!!!!

SO would you rather have some livestock killed if a short develops or a human?????????

BTW, most shorts do NOT exist between the "hot" and ground, but between the "hot" and "common". Use of a GFCI protects you AND your fish from this condition......

Just had to set the record straight......

 

[RyanM]

Hi Bj, Im glad you resonded. These are the questions I asked. Im still not sure if I understand what is said in that artical and in your responce but let me ask you this. Do you feel that enough electricity would pass through you with only your hand in the tank even if you are grounded? The way I see it, well let me say this. If say some how a pump or light was exsposed to your tank.
The hot wire and the common. with or with out the ground. Do you feel that your hand would offer less resistance than a direct path back out the common wire that is right next to the black hot wire?. I am not an an expert by any sense of the word. That why I asked. This is an important issue I think. Would like to understand it. The way I see it, you with only your hand in the tank makes for a very week path to ground even if you are standing in water. The water it self is not a super conductor. If say a light was droped into the tank. What I gathered from what your saying is that you feel that the electricity would have an easier time going from the hot wire thru the water and also thru your 99% dry body to ground if you are indeed grounded rather than a direct path back out thru the common or ground from the unit its self. If a ground probe is used I would still think it would be a lot less resistance to go straight to the common or the ground rather than go all the way thru the water to the probe and out to ground.

This is what I am having troubles with.

BTW, I respect you as an electrical engineer and welcome your comments on the issue. I really do.

 

[bjromaine]

Ryan,
If there is voltage and/or current potential in the tank and you put your hand in the tank and you are grounded......ZAPPP!!!!

Remember your body is 90% water.......it is NOT dry....

I am not really understanding your question.....
"The hot wire and the common. with or with out the ground. Do you feel that your hand would offer less resistance than a direct path back out the common wire that is right next to the black hot wire" ( I don't know how to quote, lol)

I think you might be questioning, for lack of a better term, the conductivity of water.
Look at it this way, if you are in a lake swimming, would you want to remain in the water with a thunderstorm in the area?

Water is one of the best "common" conductors of electricity that there is. By "common" I mean, excluding exotic materials created for the purpose of conducting electricity.

You should think of water the same as you would think of a bare wire. If a bare wire was in the water and you put a ground bare wire in the other end of the tank, the amount of electricity flowing into the tank would be almost exactly the same as flowing out....in other words, water would not provide much of a resistance to the flow of electricity, thusly a good conductor.

Yes, if you put your hand in the water AND there is a voltage potential, the shock you would receive or not receive, it is fully dependant on what level of a ground you provided.
If you were standing on a dry rubber mat, you may not provide any ground path at all.
If you were standing in a puddle of water, which does occur around tanks as much as we hate to admit it, AND that water was dripping through the floor and dripping on a metal pipe, you would be a very good ground path.....it is all dependant on the circumstance.

 

[RyanM]

Agreed, it is all dependant on the circumstances. Very much so infact. For example, A shrimp or crab chews thru the wires on your power head. It does happen so Ive read at least. If that chewed wire happens to be the black wire, and your tank isnt grounded then you will not get shock provided you arent standing in water but if the tank is grounded thru a probe than you have provided the path to ground. I dont think that is a xommon happenstance but it could along with many many other possible senerios.

I really should point this in the perspective as in how it came to me to even be thinking about it.

I asked what did people use a ground probe for? The responce i got was " It is believed that stray electicity is running thru our tanks from the light and other equipment that creats a kinda of noise that can or does irrritate your fish. the probe provideds a path to ground for that stray noise to be eliminated.

My responce to that was, The probe in that instance would be doing more harm than good do to the fact that now you are creating flow where non would have been to begin with. Thats bad.

While pondering that question I starting thinking about the plusses and minuses. There is no doubt that in certain instances a probe would save your live. And I would not and am not telling ANYONE not to use a probe. Im am simply trying to comprehend.

 

[Gary Majchrzak]

I've placed my hand in aquariums containing
1) a broken exposed heater
2) a shorting powerhead
3) a powerhead with a chewed (exposed) powercord

I've been jolted pretty good.
The worst that I've experienced happened while standing barefoot (socks only) on a concrete floor and placing my hand into a sump containing a ground probe and a broken heater. Ouch.
If only I'd known the heater was broken I would have unplugged it. It's a cheap way to get a new hairdo. :wildone:

 

[RyanM]

Gary, Ill bet that didnt feel good. Ill also bet you give what your standing in a little more thought now . Im thankfull that I not had any problems with that yet. I say yet because im sure it happens alot and my time will come. I do my very best to be as insulated as I can around my tank. And believe it or not I look at my tank before plopping my hand into it. Fish floating would be a sure sign of bad things happening. If my fish are fine and im not grounded then i feel safe to assume it is ok to put my hands in my tank. By safe I mean not a deadly jolt.

 

[bjromaine]

BTW Ryan, to my limited knowledge, the limited amount of electricity that might be available in an aquarium, does not create any noise......not sure where someone came up with that or if they used the term "noise" meaning something else.
IMHO.....The amount of current that it would take to seriously injure or kill a human is very seldom found in an aquarium. It would require a serious malfunction of a device.
Gary's example of the broken heater is not all that uncommon.
It is best to get in the habit of touching the water with the back of your hand first before diving in.
The reason for that is, AC current causes the body's muscles to contract. If you touch the water with the back of your hand and there is ample current available to harm you, the muscles in your arm and hand will contract causing your hand to pull out of the water.

I was not attempting to advise anyone on whether to use a grounding probe or not but I was trying to explain the pros and cons clearly.

I myself have never had a grounding probe until I recently bought a Won titanium heater, which is grounded. Since the heater only lasted 2 weeks (arrrrrrrrggggggghhhhh) I no longer have a grounding probe.
However I do have everything on a GFCI circuit, which I believe provides protection against 85% of shocks and has no negative effect on the livestock.

Hope all this helps...

 

[RyanM]

<a href=showthread.php?s=&postid=9205529#post9205529 target=_blank>Originally posted</a> by bjromaine

Gary's example of the broken heater is not all that uncommon.
It is best to get in the habit of touching the water with the back of your hand first before diving in.
The reason for that is, AC current causes the body's muscles to contract. If you touch the water with the back of your hand and there is ample current available to harm you, the muscles in your arm and hand will contract causing your hand to pull out of the water.

That is the best advise I have heard thus far from anyone. I would only add one more thing. Even with the use of a ground probe it is NEVER a good idea to be in contact with anything that may ground you..ie standing in a puddle of water or one hand on your lighting fixture while your hand is in your tank.

Be Safe.

 

[RCBrooke]

Yup, I use two. One on each circuit. I've zapped myself enough to be extra cautious. I'd rather fry ten tanks than me once. Testing with the back of the hand works great for the muscle contractions but your hand can be numb for hours (nerves). I zapped myself good once messing around in the back of an old tube TV. I think I got the fly yoke.

Also I'm trying very hard to not buy any equipment that doesn't have a ground 3 prong plug.

Randy

 

[rjrobert]

Gary, Shouldn't a GFCI have tripped before you got zapped? Did you just not have a GFCI installed at the time or did you have it and you still get zapped.

For points on this discussion. I had a ground probe for about 3 years on my tank but actually unplugged it 2 weeks ago cause I needed the outlet for a new pump.