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grounding probes (1 Viewer)
- Thread starter dillo
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Niko5
Guest
Oh man you relaly dont want to start up that conversation haha if yOu go to reefcentral and search on that you will fine years and years of reading and still never get a firm answer yes or no
MarkieB
Guest
I agree with Niko...the answer is Yes or No.
Lets' look at the possibilities.
Like myself, you get one for 15-25 $$$ and install it.
Ok let's say it is needed and does work.
Just how much electricity do we have in our tanks? For me it is
8 lines each with 120 Volts running through them. Thats a lot of juice!
I figure if it works great! If it does not, then I wasted $15.00 and dont even know it! For the money it's not even worth it for me to wonder.
Lets' look at the possibilities.
Like myself, you get one for 15-25 $$$ and install it.
Ok let's say it is needed and does work.
Just how much electricity do we have in our tanks? For me it is
8 lines each with 120 Volts running through them. Thats a lot of juice!
I figure if it works great! If it does not, then I wasted $15.00 and dont even know it! For the money it's not even worth it for me to wonder.
G
Guest
Grounding Probes
As an electrical engineer, I have always been amazed at the assumptions and rumors concerning electrical power and lighting in our hobby. I have finally come to the conclusion that it is something having to do with fish, whether aquariums or fishing, that causes us to be vunerable to the lighting and lure manufacturers.
Ground probes are marketed as either a safety device, (The common misconception is if its grounded, its safe), or as something which will remove 'stray current' from our aqauriums and thereby make our corals and fish healthy and happy. Wrong on all counts!. Lets take a look at what is going on at the speed of light.
Think of electricity like your closed loop, but using electrons instead of water. A power source such as a generator (pump) pushes electrons down a conductor (pipe), where is does some work by powering a load (a waterwheel???). The current then returns to its source down the second wire. For current to flow, there has to be difference in potential (electrical) across the load. A single wire, connected to lots of voltage will have no current flowing in it if it is not connected back to the source of power or to "ground". And it is the current that does the work. Your pump can be putting out 100 psi, but if you do not open the valve, no work will get done.
For the purpose of this discussion, lets assume that all this begins at a circuit breaker, a "safety device" at the start of the circuit. Circuit breakers do not exist to keep you from being electrocuted, they are used to keep your humble home from burning down....thats right, they are a FIRE protection device. To accomplish this feat, here is how they work. When electrical current flows in a conductor it generates heat, the more the current, the more heat it generates. Heat builds up in the current sensing element of the cicuit breaker until it "trips" the breaker, which opens a switch inside the breaker, shutting off the power. This keeps the wire in your wall from overheating and burning down your house. It does not protect you from being the next electrical fatality. Why?
The ground wire that is connected to electrical equipment, i.e that third prong on the plug is to take "objectional" current back to the source so the breaker will operate, IF and ONLY IF voltage accidentally escapes the circuit via a frayed wire etc, and it charges up the steel case surrounding your toaster oven. The ground wire wire returns the voltage back to its source so the breaker can "see" enough current to trip open. Since there would be very little resistance in the copper ground wire (theoretically), the current would rapidly rise, and the breaker would open when this current reached the preset breaker value, usually 15 or 20 amps on a household plug. If you happen to be touching the toaster oven when this happens and your feet are grounded solidly, or if the electrican just forgot to hook the ground wire to your receptacle, part of the current will flow though you too. If enough current flows through you, and not back to the source, the breaker may never operate becuase the current will be flowing thru the supply wire, through you to ground and then through the high resistant ground back to the source. If there is a high enough resistance in this circuit, it will limit the amount of current the breaker 'sees' and the breaker will keep on keeping on.... More resistance (your body, the ground, bad connections in the ground circuit etc) = less current in an electrical circuit.
It takes a very small amount of electrical current to let you take advantage of that funeral plan you told the telemarketer you didn't need. A very, very small amount of current, as a matter of fact. A 30 watt light bulb, operating at 120 volts, has 30/120 = 0.25 amp flowing through it. That would be 250/1000 of an amp or 250 milliamps (ma).
Current level
(in milliamperes) Probable effect on human body
1 mA Perception level. Slight tingling sensation. Still dangerous under certain conditions.
5 mA Slight shock felt; not painful but disturbing. Average individual can let go. However, strong involuntary reactions to shocks in this range may lead to injuries.
6-30 mA Painful shock, muscular control is lost. This is called the freezing current or "let-go" range.
50-150 mA Extreme pain, respiratory arrest, severe muscular contractions. Individual cannot let go. Death is possible.
1000 mA Ventricular fibrillation (the rhythmic pumping action of the heart ceases.) Muscular contraction and nerve damage occur. Death is most likely.
A 30 WATT light bulb use enough current to kill you 5 times over!!
When that 15 amp breaker finally trips, you will have 1500 ma flowing thru your body - i.e. your widow will be getting an insurance check. Enter GFCI
Ground fault curcuit interrupters, or GFCIs work a different way, they 'look' at the current going out and the current coming back. If there is a difference of more than 6 ma, they open the circuit to keep you safe. If you have a ground probe in your tank, and your new Rio powerhead shorts out in the tank, part of the current will flow through the ground probe and not get back to the GFCI and it will trip. So, does the ground probe protect you?...NO!, the GFCI does. IF you have no GFCI, and you have a ground probe, until such time as there is 15+ Amps coursing through your tank, no ground probe can make the breaker trip. Resistance in the seawater and through the grounding circuit will prevent the current from reaching the trip point. Stick your hand in the tank and you have just become part of a circuit where a lot of electical current is flowing and you can still sustain a fatal shock.
Bottom line - Ground probes DO NOT protect you unless you are using a GFCI circuit AND the ground probe is solidly connected back to the source of power. If you are a risk taker, go ahead and assume that the wiring in your house is all connected properly and that the wall receptacle ground is really grounded solidly, plug in your new titanium ground probe and get that warm fuzzy feeling of bliss that only ignorance can bring. Save your money on the ground probe, and buy a GFCI outlet instead...and TEST the GFCI to make sure it trips at 6 ma. Home Depot sells GFCI test plugs--plug it in, turn the knob and if it doesn't trip, you aren't safe!
Some things to consider-----
A regular 15 amp circuit breaker must open the circuit within 6 cycles (96/1000 of a second) ONE TIME, when it is new, to be within specifications, after that it may take longer - at 15 amps, you will sustain a fatal shock in as little as 3 cycles!
A GFCI costs less than a titanium ground probe!!!!!
Testing your new GFCI is a REQUIREMENT!
UPS and GFCI.... I also saw a post about hooking up a UPS (Untinterruptable Power Supply) to a power head to keep water moving when there is a power loss. Buy an extension cord type GFCI (also from Home Depot), plug it in to the output of your UPS, TEST IT!!!! and plug your powerhead into the extension cord. You do not have to plug the UPS into a GFCI, and if you get across the output of a UPS, it will not trip a GFCI on the supply side.
Simply put, if you are operating one piece of electrical equipment, lighting, pumps, powerheads, chillers, heaters, or anything else that operates at 120 volts or more, it is around saltwater and it is not connected via a GFCI circuit, you are a finalist for the Darwin Award and deserve to be removed from the shallow end of the Gene Pool. DON'T DO IT! And if you do, tell your soon to be widow I want first crack at your corals....
As an electrical engineer, I have always been amazed at the assumptions and rumors concerning electrical power and lighting in our hobby. I have finally come to the conclusion that it is something having to do with fish, whether aquariums or fishing, that causes us to be vunerable to the lighting and lure manufacturers.
Ground probes are marketed as either a safety device, (The common misconception is if its grounded, its safe), or as something which will remove 'stray current' from our aqauriums and thereby make our corals and fish healthy and happy. Wrong on all counts!. Lets take a look at what is going on at the speed of light.
Think of electricity like your closed loop, but using electrons instead of water. A power source such as a generator (pump) pushes electrons down a conductor (pipe), where is does some work by powering a load (a waterwheel???). The current then returns to its source down the second wire. For current to flow, there has to be difference in potential (electrical) across the load. A single wire, connected to lots of voltage will have no current flowing in it if it is not connected back to the source of power or to "ground". And it is the current that does the work. Your pump can be putting out 100 psi, but if you do not open the valve, no work will get done.
For the purpose of this discussion, lets assume that all this begins at a circuit breaker, a "safety device" at the start of the circuit. Circuit breakers do not exist to keep you from being electrocuted, they are used to keep your humble home from burning down....thats right, they are a FIRE protection device. To accomplish this feat, here is how they work. When electrical current flows in a conductor it generates heat, the more the current, the more heat it generates. Heat builds up in the current sensing element of the cicuit breaker until it "trips" the breaker, which opens a switch inside the breaker, shutting off the power. This keeps the wire in your wall from overheating and burning down your house. It does not protect you from being the next electrical fatality. Why?
The ground wire that is connected to electrical equipment, i.e that third prong on the plug is to take "objectional" current back to the source so the breaker will operate, IF and ONLY IF voltage accidentally escapes the circuit via a frayed wire etc, and it charges up the steel case surrounding your toaster oven. The ground wire wire returns the voltage back to its source so the breaker can "see" enough current to trip open. Since there would be very little resistance in the copper ground wire (theoretically), the current would rapidly rise, and the breaker would open when this current reached the preset breaker value, usually 15 or 20 amps on a household plug. If you happen to be touching the toaster oven when this happens and your feet are grounded solidly, or if the electrican just forgot to hook the ground wire to your receptacle, part of the current will flow though you too. If enough current flows through you, and not back to the source, the breaker may never operate becuase the current will be flowing thru the supply wire, through you to ground and then through the high resistant ground back to the source. If there is a high enough resistance in this circuit, it will limit the amount of current the breaker 'sees' and the breaker will keep on keeping on.... More resistance (your body, the ground, bad connections in the ground circuit etc) = less current in an electrical circuit.
It takes a very small amount of electrical current to let you take advantage of that funeral plan you told the telemarketer you didn't need. A very, very small amount of current, as a matter of fact. A 30 watt light bulb, operating at 120 volts, has 30/120 = 0.25 amp flowing through it. That would be 250/1000 of an amp or 250 milliamps (ma).
Current level
(in milliamperes) Probable effect on human body
1 mA Perception level. Slight tingling sensation. Still dangerous under certain conditions.
5 mA Slight shock felt; not painful but disturbing. Average individual can let go. However, strong involuntary reactions to shocks in this range may lead to injuries.
6-30 mA Painful shock, muscular control is lost. This is called the freezing current or "let-go" range.
50-150 mA Extreme pain, respiratory arrest, severe muscular contractions. Individual cannot let go. Death is possible.
1000 mA Ventricular fibrillation (the rhythmic pumping action of the heart ceases.) Muscular contraction and nerve damage occur. Death is most likely.
A 30 WATT light bulb use enough current to kill you 5 times over!!
When that 15 amp breaker finally trips, you will have 1500 ma flowing thru your body - i.e. your widow will be getting an insurance check. Enter GFCI
Ground fault curcuit interrupters, or GFCIs work a different way, they 'look' at the current going out and the current coming back. If there is a difference of more than 6 ma, they open the circuit to keep you safe. If you have a ground probe in your tank, and your new Rio powerhead shorts out in the tank, part of the current will flow through the ground probe and not get back to the GFCI and it will trip. So, does the ground probe protect you?...NO!, the GFCI does. IF you have no GFCI, and you have a ground probe, until such time as there is 15+ Amps coursing through your tank, no ground probe can make the breaker trip. Resistance in the seawater and through the grounding circuit will prevent the current from reaching the trip point. Stick your hand in the tank and you have just become part of a circuit where a lot of electical current is flowing and you can still sustain a fatal shock.
Bottom line - Ground probes DO NOT protect you unless you are using a GFCI circuit AND the ground probe is solidly connected back to the source of power. If you are a risk taker, go ahead and assume that the wiring in your house is all connected properly and that the wall receptacle ground is really grounded solidly, plug in your new titanium ground probe and get that warm fuzzy feeling of bliss that only ignorance can bring. Save your money on the ground probe, and buy a GFCI outlet instead...and TEST the GFCI to make sure it trips at 6 ma. Home Depot sells GFCI test plugs--plug it in, turn the knob and if it doesn't trip, you aren't safe!
Some things to consider-----
A regular 15 amp circuit breaker must open the circuit within 6 cycles (96/1000 of a second) ONE TIME, when it is new, to be within specifications, after that it may take longer - at 15 amps, you will sustain a fatal shock in as little as 3 cycles!
A GFCI costs less than a titanium ground probe!!!!!
Testing your new GFCI is a REQUIREMENT!
UPS and GFCI.... I also saw a post about hooking up a UPS (Untinterruptable Power Supply) to a power head to keep water moving when there is a power loss. Buy an extension cord type GFCI (also from Home Depot), plug it in to the output of your UPS, TEST IT!!!! and plug your powerhead into the extension cord. You do not have to plug the UPS into a GFCI, and if you get across the output of a UPS, it will not trip a GFCI on the supply side.
Simply put, if you are operating one piece of electrical equipment, lighting, pumps, powerheads, chillers, heaters, or anything else that operates at 120 volts or more, it is around saltwater and it is not connected via a GFCI circuit, you are a finalist for the Darwin Award and deserve to be removed from the shallow end of the Gene Pool. DON'T DO IT! And if you do, tell your soon to be widow I want first crack at your corals....
Niko5
Guest
What He said!!! and Ill take the Tank and Live rock
MarkieB
Guest
Re: Grounding Probes
And yes, GFCI are a MUST!
I will take it one step further.
Never put your hand in the tank until you unplug the main power lines.
Do we do this...
most likely not.
I do..Why because my neighbor got killed by putting his hand in the tank.
People do die from tanks! I have proof!
I totally agree and have this exact set up!obtusewit said:
And yes, GFCI are a MUST!
I will take it one step further.
Never put your hand in the tank until you unplug the main power lines.
Do we do this...
most likely not. I do..Why because my neighbor got killed by putting his hand in the tank.
People do die from tanks! I have proof!
G
Guest
Must remember to get that big insurance policy. he he J/k
I know I shouldn't joke about it, beign an EE also, I can't help it. When we bought our home there wasn't one GFC in it! I replaced all of them in the house putting GCF's in the kitchen, baths, and where tanks are.
he he J/kI know I shouldn't joke about it, beign an EE also, I can't help it. When we bought our home there wasn't one GFC in it! I replaced all of them in the house putting GCF's in the kitchen, baths, and where tanks are.
t0mmy108
Guest
obtusewit, will you come to my house to install some GFCI's?
Appreciate all of the educated info but I was not asking about grounding probes for safety reasons-I have a colt coral that refuses to open fully and I was curious to know if stray voltage might be the problem. And yes. my water quality is fine.
G
Guest
Well dillo, if you really want a grounding probe, you could rent mine.
Or a poor mans way of making sure that you don't have to worry about stray voltage nor your colt is get a copper wire and ground your tank with it.
(Please people do not use the second method. I am not responsible if you do, and all your corals die. It was only a joke.)
Or a poor mans way of making sure that you don't have to worry about stray voltage nor your colt is get a copper wire and ground your tank with it.
(Please people do not use the second method. I am not responsible if you do, and all your corals die. It was only a joke.)
G
Guest
No, but I did have my sps bleech and my xenia die because of to much stray voltage in the tank, I say stray for the GFCI never popped, while my heater was shocking the tank.
G
Guest
Ah, haven't added it yet, but it would have thrown the GFCI, or at least I think it would have if I would have had a grounding probe. My heater broke all the way through, the problem stopped when I unplugged the heater, so did the big white flashes.
The bad smell took a little longer, thank goodness it was coming from the tank and not my pants.
The bad smell took a little longer, thank goodness it was coming from the tank and not my pants.
G
Guest
Are you close to me? I got one that I am currently not using.
G
Guest
Ah, ok, well your welcome.
