Rickyrooz1
Acropora Nut
I rechecked the system and I'm getting the reading from my TEK II T5 retrofit. None of the cable are in the water but whenever I touch the reflector and with my other hand in the water I get shocked. Anyone have an idea?
Stray Voltage
- Thread starter Rickyrooz1
- Start date
Rickyrooz1
Acropora Nut
How do I ground the reflector? Attach a wire to the reflector to a ground cable? Also, I am unsure what setting I should be using on the voltmeter to find a stray volt. Right now I am plugging the black cord into the ground outlet and the red cord is touching the water. I have it set on ACV 200. I slowing plug in each piece of equipment until I get a reading on the meter. When I unplugged everything I got a reading of 0.00, when I had the T5's on I got a reading of 1.3! If I touched the reflector it jumped anywhere from 24-78. Was this from the stray being connected to the ground?
jdieck
New member
Fluorecent bulbs (PC, T12, T8, T5 etc.) create a magnetic field that induces eddie currents in the metal of the reflector which in turn set the reflector at a diffeent potential than the ground and the aquarium.
The power cable from the outlet to the ballas must have had three wires (neutral white, Hot Black and ground green) just conect a wire from were the green cable is attached to the ballast body to the screw used to attach the lamp clip to the reflector so the green wire is attached to the metal reflector. That simple.
The way your are measuring is OK, start at a higher than 120 volts and keep on lowering the scale until you get a reading.
The 1.3 is typical of an induced voltage from the reflectors, when you touch it you transfer part of that potential to the aquarium so the voltage of the aquarium versus the ground increases.
Once you ground the reflectors that shall go away or significantly reduce.
Rickyrooz1
Acropora Nut
Thanks, am I using the right setting to find a volt in the tank?
jdieck
New member
Sorry, I was editing the post while you were typing.
The way your are measuring is OK, start at a higher than 120 volts and keep on lowering the scale until you get a reading.
The 1.3 is typical of an induced voltage from the reflectors, when you touch it you transfer part of that potential to the aquarium so the voltage of the aquarium versus the ground increases.
If your meter also has DC you can try also measuring the DC although most of the voltage in our systems will be AC.
Once you ground the reflectors that shall go away or significantly reduce
The way your are measuring is OK, start at a higher than 120 volts and keep on lowering the scale until you get a reading.
The 1.3 is typical of an induced voltage from the reflectors, when you touch it you transfer part of that potential to the aquarium so the voltage of the aquarium versus the ground increases.
If your meter also has DC you can try also measuring the DC although most of the voltage in our systems will be AC.
Once you ground the reflectors that shall go away or significantly reduce
Re: Stray Voltage
Voltage is irrelevant. It's CURRENT which causes problems. You can put a little 9 or 12 volt battery on your tongue and you get a little buzz. Try that with a 12 volt car battery which puts out 60 plus AMPS vs the milliamps of a little battery and you could get dead.
In any case, there should be no voltage or current passing through the tank. If you know what piece of equipment is doing this get rid of it!
THEN-and this is ABSOLUTELY A MUST!....install a grounding probe in your tank. You can try to make one but the tricky part is finding a conductive metal that will not react with the salt water. Just buy a titanium probe - $20 or less.
It's the cheapest piece of equipment you can buy that could potentially save tank equipment, livestock, and possibly your life.
JUST DO IT!
<a href=showthread.php?s=&postid=15040279#post15040279 target=_blank>Originally posted</a> by Rickyrooz1
Can a stray volt 1.8-0.8 volts kill fish or coral? I have a Mag Drive 12 that was adding 1.8 volts into my water. I added silicone around the powercord opening and now 0.8 volts are going into the water. I checked all my other pumps, heaters, and lights and all read 0.0 on the meter. This is the voltmeter I used on ACV 200.
Voltage is irrelevant. It's CURRENT which causes problems. You can put a little 9 or 12 volt battery on your tongue and you get a little buzz. Try that with a 12 volt car battery which puts out 60 plus AMPS vs the milliamps of a little battery and you could get dead.
In any case, there should be no voltage or current passing through the tank. If you know what piece of equipment is doing this get rid of it!
THEN-and this is ABSOLUTELY A MUST!....install a grounding probe in your tank. You can try to make one but the tricky part is finding a conductive metal that will not react with the salt water. Just buy a titanium probe - $20 or less.
It's the cheapest piece of equipment you can buy that could potentially save tank equipment, livestock, and possibly your life.
JUST DO IT!
And even with grounding probes and gfci's, there is no guarantee it will all work the way you want or expect it to. Worst shock I ever got was from a leaking pump in a system with both gfci and grounding probe. The gfci didn't trip, but the main breaker did :eek1:
Mike31154
New member
Grounding probe is NOT a MUST, GFCI is not either, but a GFCI has the potential of saving your life, not sure I'd have the same confidence in a grounding probe.
The less equipment with power cords you have physically submerged in your system, the safer. VorTech powerhead, cord outside (or closed loop for water movement), external return pump, cord outside. That leaves the heater(s) and you can do a lot in that regard by not submerging the control head of any heater, even the "fully submersible" ones. Keep the cord above water.
The less equipment with power cords you have physically submerged in your system, the safer. VorTech powerhead, cord outside (or closed loop for water movement), external return pump, cord outside. That leaves the heater(s) and you can do a lot in that regard by not submerging the control head of any heater, even the "fully submersible" ones. Keep the cord above water.
Most of you are wrong.
Most of you are wrong.
Sorry, but many of the comments posted here are just wrong. One needs to understand how electricity behaves and what a ground and GFI do.
Some of the silly comments:
"Grounding probe is NOT a MUST, GFCI is not either, but a GFCI has the potential of saving your life, not sure I'd have the same confidence in a grounding probe."
Totally wrong on both counts. But then - why would you say a GFI is not a must but it has the potential to save your life?
" Also since the fish are not grounded, they will not be hurt by the voltage"
Are you serious? The fish are in the water. The water is touching the tank and anything in it. Try sticking the end of an extension cord in your tank (water only) and plug it in. No- DON'T! You can hold an plugged in cord and wave it in the air. No ground-no problem. Put it in the water and it will blow the fuse and your fish. Water is an excellent conductor of electricity. The only way for it not to be grounded would be if the tank had nothing connected to it which plugs in, AND it was sitting on a try insulated base.
There was also a comment about if you DON'T have a probe there is no ground so no voltage. THE OPPOSITE IT TRUE!
Now the techincal/theoretical part:
Stray voltages leaking to ground are pretty common. The most common problem happens when wiring is reversed (not just hot or neutral to ground but hot and neutral). Electricity ALWAYS takes the path of least resistance. If you provide one in your tank - like the probe securely fastened to a ground-the current will take that path - away from the tank and to the ground. If you don't think that's true then lightening rods are the scam of the century.
YOU MUST PROVIDE A SOLID GROUND IN YOU SYSTEM INCLUDING THE WATER IN THE TANK TO ALLOW STRAY CURRENTS A SAFE WAY OUT.
GFI's
GFI's offer protection by monitoring the current differential between the hot and neutral wires in the circuit. It should always be the same. If an imbalance occurs then it trips. That's why they are super sensitive and are required by Code in bathrooms/kitchens or any outlets near a source of water. A bit of moisture will cause the GFI to trip before you get a shock.
Note that this imbalance is not related to overcurrent issues. You can have balance but too much current. That's why a circuit breaker will trip in a short situation, but the GFI may not.
There are 3 situations and solutions, all of which must be in place to be safe.
1-Overcurrent - short circuits. This are the breakers or fuses. Unfortunately, by the time they trip people and animals may be dead.
2-Imbalance of current flow which indicates a problem. The GFI will trip very very quickly and should provide enough protection.
3-Stray voltage/current. This can come from anywhere, even if the source is not part of the tank system. Like if you dropped another plugged in appliance into the tank or if it was struck by lightening. (-; A ground probe will direct this current to ground and away from people and livestock.
PLEASE DON'T ignore this information - take it as gospel. Sorry if I sound rude but this hobby should NOT be life threatening.
Lastly, if you identify any piece of equipment which is generating stray voltages, tripping GFI's or breakers after you confirm that it is properly wired - GET RID OF IT!
I'll take any and all criticisms if only one person is saved from harm.
Most of you are wrong.
Sorry, but many of the comments posted here are just wrong. One needs to understand how electricity behaves and what a ground and GFI do.
Some of the silly comments:
"Grounding probe is NOT a MUST, GFCI is not either, but a GFCI has the potential of saving your life, not sure I'd have the same confidence in a grounding probe."
Totally wrong on both counts. But then - why would you say a GFI is not a must but it has the potential to save your life?
" Also since the fish are not grounded, they will not be hurt by the voltage"
Are you serious? The fish are in the water. The water is touching the tank and anything in it. Try sticking the end of an extension cord in your tank (water only) and plug it in. No- DON'T! You can hold an plugged in cord and wave it in the air. No ground-no problem. Put it in the water and it will blow the fuse and your fish. Water is an excellent conductor of electricity. The only way for it not to be grounded would be if the tank had nothing connected to it which plugs in, AND it was sitting on a try insulated base.
There was also a comment about if you DON'T have a probe there is no ground so no voltage. THE OPPOSITE IT TRUE!
Now the techincal/theoretical part:
Stray voltages leaking to ground are pretty common. The most common problem happens when wiring is reversed (not just hot or neutral to ground but hot and neutral). Electricity ALWAYS takes the path of least resistance. If you provide one in your tank - like the probe securely fastened to a ground-the current will take that path - away from the tank and to the ground. If you don't think that's true then lightening rods are the scam of the century.
YOU MUST PROVIDE A SOLID GROUND IN YOU SYSTEM INCLUDING THE WATER IN THE TANK TO ALLOW STRAY CURRENTS A SAFE WAY OUT.
GFI's
GFI's offer protection by monitoring the current differential between the hot and neutral wires in the circuit. It should always be the same. If an imbalance occurs then it trips. That's why they are super sensitive and are required by Code in bathrooms/kitchens or any outlets near a source of water. A bit of moisture will cause the GFI to trip before you get a shock.
Note that this imbalance is not related to overcurrent issues. You can have balance but too much current. That's why a circuit breaker will trip in a short situation, but the GFI may not.
There are 3 situations and solutions, all of which must be in place to be safe.
1-Overcurrent - short circuits. This are the breakers or fuses. Unfortunately, by the time they trip people and animals may be dead.
2-Imbalance of current flow which indicates a problem. The GFI will trip very very quickly and should provide enough protection.
3-Stray voltage/current. This can come from anywhere, even if the source is not part of the tank system. Like if you dropped another plugged in appliance into the tank or if it was struck by lightening. (-; A ground probe will direct this current to ground and away from people and livestock.
PLEASE DON'T ignore this information - take it as gospel. Sorry if I sound rude but this hobby should NOT be life threatening.
Lastly, if you identify any piece of equipment which is generating stray voltages, tripping GFI's or breakers after you confirm that it is properly wired - GET RID OF IT!
I'll take any and all criticisms if only one person is saved from harm.
Rickyrooz1
Acropora Nut
narwal, how should the grounding probe be hooked up? To the outlet in the wall or to a GFCI?
Rickyrooz1
Acropora Nut
When I set the meter to DCV 20 I get a reading of 0.15, when I set it to ACV 200 i get a reading of 0.3. What does this mean and which setting should I be using to read underwater equipment? Also, should I be connecting the black probe in the ground socket and the red probe touching the water or is this wrong?
Probe Hookup
Probe Hookup
A store bought probe usually comes with a grounded plug which you can plug into any outlet. So long as ALL your power bars,etc. are grounded you can plug it in anywhere, but not into the GFI circuit or any power bar, etc. To be sure I plug mine into the wall outlet which I have checked for correct wiring.,
You can get a simple tester at Home Depot for around $15 which has lights that show any problem like no ground, short, hot/neutral reversed, etc.
Probe Hookup
A store bought probe usually comes with a grounded plug which you can plug into any outlet. So long as ALL your power bars,etc. are grounded you can plug it in anywhere, but not into the GFI circuit or any power bar, etc. To be sure I plug mine into the wall outlet which I have checked for correct wiring.,
You can get a simple tester at Home Depot for around $15 which has lights that show any problem like no ground, short, hot/neutral reversed, etc.
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jdieck
New member
Black to the round ground socket and red to the water is fine to measure the voltage. To measure the actual voltage a ground probe should not be present.
Although a scale of ACV 200 is high for such a small reading I would say that what you are seeing is just some electrical noise and even a potential galvanic efect (Like a battery) produced by the water vs metal specially using a digital meter.
Those readings shall have no bearing in your system assuming those were measured without a ground probe installed.
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Re: Re: Most of you are wrong.
Re: Re: Most of you are wrong.
Actually under typical conditions an aquarium is insulated from ground. Even when there is equipment submerged, all of it is insulated, wires, pumps, pump cases, windings etc. as no energized metal parts touch the water, PVC pipes, glass and acrylic insulate the water from metal stands and wood stands themselves insulate the ground.
>>>Of course you are correct. But with all the water, moisture, possible small drips or leaks, etc. I wouldn't rely on the assumption that the tank is fully insulated.
Again, not without a GFCI.
Seems you are mixing apples and oranges here. Lighting is generated outside of the system and the lighting rods and ground wires installed above the transmission power lines are to elevate the ground potential over the house , building or equipment so electrically speaking they are for electrical effects buried under ground so current generated by lighting will not travel the trough the building or the power lines.
>>>Okay, maybe a poor example. The point I was trying to make was that a solid ground provides excellent protection. As for the GFI - now you are mixing apples and oranges. A GFI interrupts the current in a ground fault situation. A probe merely redirects it to ground.
In the case of a grounding probe in fact it provides a path for the current to travel trough the system, in this case the aquarium water then turning the system into a current conductor, in other words the fish in this case becomes part of the conductor.
>>>Again, you are assuming that the tank is totally insulated from ground. This approach is not safe and the reason why we rely on grounding as opposed to insulation. In any case, it's a good idea to have a safe path to ground.
If the water is grounded via a probe and there is a short circuit (say the insulation on a powerhead wire cracks) this is what happens:
a) Most times than not the short circuit is not perfect, this means that there will still be resistance thus the current may not be high enough to trip the breaker but high enough to kill everything.
>>> A short is either a short or not. If there is one you have problems. But an intermittent short may behave as you say. That's exactly why you need a ground probe to direct stray voltage/current to ground.
b) Similarly if there is splashing on a plug there will be sparking but may not reach the tripping current but the sparking will generate a fire. Given the large number of incidents in this case, NEMA is trying to enforce the use of a new device that cuts the power not because of high current like breaker, nor because current to ground like a GFCI but because the arc itself. These are now called AFCI (Arc Fault circuit interrupters)
>>>You don't understand how a GFI works, but that is very common given the name GROUND fault interrupter. It has nothing to do with ground in how it monitors the circuit. In a good circuit there is a balance between the hot and neutral when anything is in the circuit. If for some reason (like a short) this balance is disturbed because some of the current is flowing elsewhere (like to you or ground) instead of all back to neutral. The GFI trips when this balance is disturbed and it is very sensitive so even tiny imbalances trigger the protection.
c) Finally if the water is perfectly grounded and there is an energized casing or reflector like in the case were salt creep has shorted a hot line to the hood or reflector or to the casing of a metallic external pump motor and you touch the metal while working in the water because the water grounding is good then you become the conductor between the casing and the water so you will get electrocuted while if the water were not perfectly grounded the current will go from the hood or reflector trough you directly to the ground and to do so got to go trough your shoe soles, carpet hardwood floor etc which all of them may provide a degree of insulation so surely you will be shocked but because the ground is not perfect there is a higher chance you will survive it.
>>>True, but do you want to rely on "there is a higher chance you will survive it?" Send the current to ground and be safe.
If you install GFCIs in all this cases (Imperfect short, splashing or aquarist conducting from water to equipment or aquarist to ground) there will always be a portion of current to ground and because a GFCI only needs 5 milliampere to trip assuming the GFCI is functional it will trip in most of the cases even if there is no current to ground like in the sparking, it generates transient voltages that mimic current to ground that may trigger the GFCI.
>>>That's why don't plug the ground probe into a GFI.
So in summary, grounding probe and GFCI, GFCI trips in most situations. In this case if you are not around (Say traveling) leaving the system without power for long time may be very detrimental but if you are around you will have an indication something is wrong.
GFCI but no grounding probe, the problem will develop but the GFCI will not trip until you touch the water to establish the ground. It will trip cutting the power when you are there. Here you will be running the risk of a defective GFCI so you can still get seriously shocked.
So the most safe installation for you is to have breaker, GFCI and grounding probe, All faults with exception of some sparking situations which require an AFCI will be detected and protected against. This is of course implying that the GFCI is tested from proper functioning at least once a month.
>>>EXACTLY. THANK YOU. PROBE AND GFI. I have to assume that no one is running a fuse box with penny instead of a fuse.
The second safest ...............<snip>
>>>Sorry, I had to cut the rest. When it comes to safety it has to be done properly. Second or third choices are not acceptable.
Thanks for your input.
Re: Re: Most of you are wrong.
Actually under typical conditions an aquarium is insulated from ground. Even when there is equipment submerged, all of it is insulated, wires, pumps, pump cases, windings etc. as no energized metal parts touch the water, PVC pipes, glass and acrylic insulate the water from metal stands and wood stands themselves insulate the ground.
>>>Of course you are correct. But with all the water, moisture, possible small drips or leaks, etc. I wouldn't rely on the assumption that the tank is fully insulated.
Again, not without a GFCI.
Seems you are mixing apples and oranges here. Lighting is generated outside of the system and the lighting rods and ground wires installed above the transmission power lines are to elevate the ground potential over the house , building or equipment so electrically speaking they are for electrical effects buried under ground so current generated by lighting will not travel the trough the building or the power lines.
>>>Okay, maybe a poor example. The point I was trying to make was that a solid ground provides excellent protection. As for the GFI - now you are mixing apples and oranges. A GFI interrupts the current in a ground fault situation. A probe merely redirects it to ground.
In the case of a grounding probe in fact it provides a path for the current to travel trough the system, in this case the aquarium water then turning the system into a current conductor, in other words the fish in this case becomes part of the conductor.
>>>Again, you are assuming that the tank is totally insulated from ground. This approach is not safe and the reason why we rely on grounding as opposed to insulation. In any case, it's a good idea to have a safe path to ground.
If the water is grounded via a probe and there is a short circuit (say the insulation on a powerhead wire cracks) this is what happens:
a) Most times than not the short circuit is not perfect, this means that there will still be resistance thus the current may not be high enough to trip the breaker but high enough to kill everything.
>>> A short is either a short or not. If there is one you have problems. But an intermittent short may behave as you say. That's exactly why you need a ground probe to direct stray voltage/current to ground.
b) Similarly if there is splashing on a plug there will be sparking but may not reach the tripping current but the sparking will generate a fire. Given the large number of incidents in this case, NEMA is trying to enforce the use of a new device that cuts the power not because of high current like breaker, nor because current to ground like a GFCI but because the arc itself. These are now called AFCI (Arc Fault circuit interrupters)
>>>You don't understand how a GFI works, but that is very common given the name GROUND fault interrupter. It has nothing to do with ground in how it monitors the circuit. In a good circuit there is a balance between the hot and neutral when anything is in the circuit. If for some reason (like a short) this balance is disturbed because some of the current is flowing elsewhere (like to you or ground) instead of all back to neutral. The GFI trips when this balance is disturbed and it is very sensitive so even tiny imbalances trigger the protection.
c) Finally if the water is perfectly grounded and there is an energized casing or reflector like in the case were salt creep has shorted a hot line to the hood or reflector or to the casing of a metallic external pump motor and you touch the metal while working in the water because the water grounding is good then you become the conductor between the casing and the water so you will get electrocuted while if the water were not perfectly grounded the current will go from the hood or reflector trough you directly to the ground and to do so got to go trough your shoe soles, carpet hardwood floor etc which all of them may provide a degree of insulation so surely you will be shocked but because the ground is not perfect there is a higher chance you will survive it.
>>>True, but do you want to rely on "there is a higher chance you will survive it?" Send the current to ground and be safe.
If you install GFCIs in all this cases (Imperfect short, splashing or aquarist conducting from water to equipment or aquarist to ground) there will always be a portion of current to ground and because a GFCI only needs 5 milliampere to trip assuming the GFCI is functional it will trip in most of the cases even if there is no current to ground like in the sparking, it generates transient voltages that mimic current to ground that may trigger the GFCI.
>>>That's why don't plug the ground probe into a GFI.
So in summary, grounding probe and GFCI, GFCI trips in most situations. In this case if you are not around (Say traveling) leaving the system without power for long time may be very detrimental but if you are around you will have an indication something is wrong.
GFCI but no grounding probe, the problem will develop but the GFCI will not trip until you touch the water to establish the ground. It will trip cutting the power when you are there. Here you will be running the risk of a defective GFCI so you can still get seriously shocked.
So the most safe installation for you is to have breaker, GFCI and grounding probe, All faults with exception of some sparking situations which require an AFCI will be detected and protected against. This is of course implying that the GFCI is tested from proper functioning at least once a month.
>>>EXACTLY. THANK YOU. PROBE AND GFI. I have to assume that no one is running a fuse box with penny instead of a fuse.
The second safest ...............<snip>
>>>Sorry, I had to cut the rest. When it comes to safety it has to be done properly. Second or third choices are not acceptable.
Thanks for your input.
AND Now..............
AND Now..............
Now that we have that out of the way we can have some fun with electricity and lighting.
I bought 4-450 watt transformers/ballasts to drive my MH lights. $40 each. The tricky part was to re-tap the transformers to run on 120v instead of 220. They are big, heavy and ugly, but because of their industrial design and capacity they don't produce much heat. Hidden from view they should last a long long time.
I also made a very handy power block which is a duplex GFI outlet wired to Decora switch mounted on a piece of wood with a nice long plug wire. It's great for doing water changes. You plug the box into any outlet and plug in your pump and can turn it on and off from beside the tank. Safe and convenient.
AND Now..............
Now that we have that out of the way we can have some fun with electricity and lighting.
I bought 4-450 watt transformers/ballasts to drive my MH lights. $40 each. The tricky part was to re-tap the transformers to run on 120v instead of 220. They are big, heavy and ugly, but because of their industrial design and capacity they don't produce much heat. Hidden from view they should last a long long time.
I also made a very handy power block which is a duplex GFI outlet wired to Decora switch mounted on a piece of wood with a nice long plug wire. It's great for doing water changes. You plug the box into any outlet and plug in your pump and can turn it on and off from beside the tank. Safe and convenient.
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