You guys are really making me sick!

If anyone would be interested in a test unit as described above, I'll build a couple of test units, if anyone would be interested - half of the returns can go to the forum or something... the rest into my tank hehe

Would it be a feasible proposal? Mods regarding rules?

btw Yes the mains trip switch only works on current. In theory you can apply 20 000 volt over the switch, if there is no current going through (short) the switch won't trip.
 
mandarinman said:
isnt it amazing how the world of reefing has been saying ground your system to get rid of stray current but instead it just completes the circuit! lets question things like lateral line erosion being attributed to bad nutrition? it will be interesting to see where this goes.
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Lateral line corrosion is also referred to stray voltage. Question is closed circuit or not?
And what actually is lateral line corrosion? I came across this many times, but still don't know what it is.
 
hmm my system is grounded , i will look into this can you tell me marcel how do you measure voltage in water using voltmeter>? i have no experience on how to do that?
 
Achilles said:
hmm my system is grounded , i will look into this can you tell me marcel how do you measure voltage in water using voltmeter>? i have no experience on how to do that?
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@Achilles

You take a normal 3 prong plug and only connect one wire to the biggest prong, which is for the earth leakage. The other end of the wire you connect to the black probe from your voltmeter. Put the 3 prong plug into a socket which is connected to the earth leakage of your mainboard. Now switch on your voltmeter, set to AC and put the red probe into the water. This will only work, after you disconnected your ground probe. Otherwise you will not get a result about the voltage.

Hope you come right. If not give me a ring. You got my number.
 
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Electrolysis only works on DC current. The principle of electrolysis by passing a current through a solution containing dissolved irons. In electrolysis there are two probes (electrodes). An anode which is a positive electrode and a cathode which is a negative electrode. When DC current is passed through the solution irons (copper, iron, silver, gold etc) these irons leave the cathode (negative electrode) go into solution and then deposit on the Anode (positive electrode). However this is not the case with all metal. Platinum and titanium do not normally participate in electrolysis.

When AC current is used the the electrodes keep swapping around as the current alternates between positive and negative. So the metal on the probes will not transfer from the one electrode (Cathode)to the water to the other electrode (anode). But gas is produced and will be seen bubbling from both electrodes.

In the experiment @Luckfish conducted he used a 19v DC laptop power supply which is why the water turned brown so quickly. This would not have been the case if the power supply was AC.

However using AC current with two electrodes in a saline solution has other implications. MOST ARE VERY DANGEROUSE. Depending on the solution the electrodes are in different chemical processes take place. One is to produce H2 and O2 which when mixed is quite an exciting experience when ignited.
 
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I do not understand that a pump that leaked 200V into the system, could not trip the earth leakage. I pinched the cord on a pump recently and I did not noticed it, and 2:15 in the morning the power tripped. 2 days after I pinching incident.

I know amp A is needed to trip the earth leakage. But a open cord or damaged pump is not transformer that pushes out milliamps.

OK I'm not an electrician. I accept if I do not understand the shocking effects of damaged pumps. @Max and @lIghty please help me understand this.
 
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@LuckyFish , thanks for a great post. Mods, can't we make this sticky?

According to what iv just read, using an aiptasia zapper is big NO NO!! Alot of reefers out there are busy zapping Aiptasia not knowing the potential risk :shocked:
 
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OK we are going to talk about AC current and two phase.

For anything to work with electricity we need to complete a circuit. That means we need a live wire and a neutral wire connected to something that is going to conduct electricity. This could be a motor, heater, light etc...

Now water (not pure water) conducts electricity and so does the human body. Lets forget about the electrolysis side of the equation for now. But when two wires are submerge in our tank water electricity passes from neutral through the water to live. In this case the earth leakage will not trip as there is no electricity going to earth. It is simply passing from live to neutral and is drawing current. The current draw is the same on live and the neutral.

Now the aquariust comes along and puts his hand in the tank. What happens is current is now being drawn to earth and the current draw on the live and neutral has a difference. That is when the earth leakage trips.

Now if an Aquariust is properly insulated, has thick insulated shoos etc then when he puts his hand into the tank he will not trip the earth leakage because there is no current being drawn to earth. This is often just felt as a small electric shock. However by one putting ones hand into the tank it all depends where the electrical current is flowing. The closer to the live and neutral the the hand is inserted in the water, the more current will flow through the hand and the bigger the shock. If the aquariust is not properly insulated then he/she becomes the grounding probe and a huge shock is felt and the earth leakage should trip.

What is the benefit of a grounding probe. Well apart from if you don't have one you could be electrocuted. As soon as any electrical current passes through, from either live or neutral to ground then the earth leakage will trip. That is if the earth leakage is working properly.

What are the disadvantages of a grounding probe. If your earth leakage is not working correctly then you will get what Marcel is referring to.

I have not found or had an issue where the small electrical currents have caused the issues Marcel has had. But one to consider and be aware of.

DC current.
This is another issue all together. If two low voltage pumps are faulty Electrolysis will take place. But again if there is a grounding probe then the earth leakage should trip. If no grounding probe then the electricity will just flow from negative to positive and irons will be deposited in your water column.
 
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Nemos Could the possibility arise that you have a ground probe in one corner of your tank and a faulty pump at the other end of the tank. The earth leakage does not trip because the distance ( resistance ) is too great, yet when you put your hand into the weter near the faulty pump you get zapped?
 
Thanks for the good read..what an eye opener..
 
dendrosa said:
Nemos Could the possibility arise that you have a ground probe in one corner of your tank and a faulty pump at the other end of the tank. The earth leakage does not trip because the distance ( resistance ) is too great, yet when you put your hand into the weter near the faulty pump you get zapped?
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And in a similar situation, could the distance between the sump and display (with water being pumped between the 2), be too great for a single ground probe to function for both?
 
yoi can also have current in your tank if you have salt residue on your cableing as it conducts electricity! this without any electrodes or broken equipment. the current runs on the outside of your cableing directly from the plug.
 
dendrosa said:
Nemos Could the possibility arise that you have a ground probe in one corner of your tank and a faulty pump at the other end of the tank. The earth leakage does not trip because the distance ( resistance ) is too great, yet when you put your hand into the weter near the faulty pump you get zapped?
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Yes. But the zap near to the pump is normally caused by the current passing from neutral through you to live rather than to earth.

Let me get a good explanation of how earth leakage works if @belindamotion does not beat me to it. :)
 
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Does anyone know why all aquarium electrical equipment is only provided with two wires? Surely it would be safer if it had 3 wires, with the 3rd ( earth wire) connected to a ss ring etc which is permanently in contact with the water. Should there be any exposure of the neutral or live to the water there would be an earth path close to the electricity wich would ensure the earth leakage trips ( assuming it is in good nick)
 
This is a very simple description of how earth leakage works as i know it. It is based on the amount of electricity entering and/or leaving the device. By device it could be an Aquarium or a motor, heater etc. When there is a difference in the amount of electricity entering and/or leaving the device it must be going somewhere. Normally to earth. So when this difference is measured (10-100mA for 40 to 100 milliseconds) the earth leakage should trip. So if there is a current less than 10mA or shorter than 40 milliseconds then the earth leakage will not trip.

This then comes back to the point of how much electrolysis with AC will take place at under 10mA? And should the earth leakage have been working as designed,and more than 100mA was drawn then it should have tripped the earth leakage.

However there are different types of earth leakage switches. Some have a bigger threshold than others. This is to stop nuisance trips. So perhaps an answer is to ensure you have a high sensitive earth leakage device on your aquarium circuit.

But what has happened to @LuckyFish and what he is saying is in my mind quite correct and something to always look out for.

We come across instances where fish just start to dye for no reason. Well yes the reason is a faulty pump that is doing what Luckyfish explains.
 
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