Gregcoyote
Aquarium Advice Addict
kdpuffer said:
Right on...but you don't want to be the path to ground. Standing in bare feet in a puddle of saltwater is a situation where I want all my electrical devices buttoned down and made as safe as possible.
stray voltage levels in saltwater aquarium
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Right on...but you don't want to be the path to ground. Standing in bare feet in a puddle of saltwater is a situation where I want all my electrical devices buttoned down and made as safe as possible.
kdpuffer
Aquarium Advice Addict
Gregcoyote said:
And that is where the GFCI comes in. Like stated before if you don't have a properly grounded receptacle it won't work properly and you have bigger issues to address. All receptacles should be properly grounded. Once your receptacle is properly grounded then your set to install GFCI's. just a side note the proper term is bonded not grounded. All the "grounds" in your house are bonds and are connected to the ground wire coming into your panel from the ground or dirt outside your house- just a little FYI for all that care lol. Another little tid bit is how GFCI's work. They monitor the difference in current between your hot and neutral wires, this is done by monitoring the magnetic field created around the wire by current flowing through the wire. When everything is good the magnetic fields are the same but once something goes wrong the magnetic fields shift and don't balance out which causes the receptacle to trip or shut off.
Gregcoyote
Aquarium Advice Addict
In my world, bonding is to bring everything down to the same potential. Done primarily for lightening protection in most of my installations, it does make the outside ground the common potential for all devices "bonded" into the system. In other words, you don't want the toaster at a different potential than the cold water faucet.
Gregcoyote
Aquarium Advice Addict
Had to do some PAR readings at the LFS, will test for voltage tomorrow.
ezy33
Aquarium Advice Addict
Found this post today and got my Fluke work meter out and tested my system at 0 volts AC. Then got my Harbor Freight $5.00 meter and had 1.4 volts AC. Maybe it's your meter reading high. Can you borrow another meter?
I have 2 grounding probes in my system but without a GFI. When my heater failed in my refugium I could feel the voltage in the water when it was plugged in. I lost most of my algae but no fish or inverts. I originally put the probes in because I had about 5 volts of stray voltage.
I have 2 grounding probes in my system but without a GFI. When my heater failed in my refugium I could feel the voltage in the water when it was plugged in. I lost most of my algae but no fish or inverts. I originally put the probes in because I had about 5 volts of stray voltage.
I have a $20 ETEK meter from walmart but I could try another one (though this one reads 122V out of a 120 outlet so probably works good). I will do that.
Did you test with your grounding probes unplugged and out of the tank?
EDIT| Also you should probably spend the $50-$100 bucks or so to get that tank on a GFI. Might save your life one day. On that note, I'm wondering how to purposely trip my GFI from my tank. For testing purposes.
ezy33
Aquarium Advice Addict
Most GFI's have a test button and a reset button. As for saving my life I'd have to move the plug strip about 5 feet, just lazy and having my system shut down IMO is worst than having some power in the system. Especially if it shuts down while I'm away for the weekend.
I've had a aquarium almost continually for 40 years SW for the last 8. I think I'll live.
I've had a aquarium almost continually for 40 years SW for the last 8. I think I'll live.
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Gregcoyote
Aquarium Advice Addict
ezy33 said:
I think your life might be worth more. If the GFI shuts down, there is a good reason for it. By that logic you should remove your circuit breakers or fuses. I've had tanks a very long time too and I use to get zapped pretty good. Didn't like it much.
My outlet does not have a test and reset button. However I used the outlet tester to verify it was grounded and then used the test button on the outlet tester to trip the circuit. It worked.
I'm just wondering if I can do it from my tank. There's a power strip and an extension cord in between the tank and the outlet. IDK, I just wanna be safe.
I don't feel the shock any more and I just tested 1.07 volts so things are looking better after I redid my electrical.
I'm just wondering if I can do it from my tank. There's a power strip and an extension cord in between the tank and the outlet. IDK, I just wanna be safe.
I don't feel the shock any more and I just tested 1.07 volts so things are looking better after I redid my electrical.
ezy33
Aquarium Advice Addict
Yes you can use your tester anywhere after the GFI. In fact one GFI installed properly at the first outlet will protect all the outlets on that circuit.
kdpuffer made some good points. Remember what he said, as little as 4mA, across your heart, can kill you. A lot of field service folks I work with will work on cabinets with one hand in their pocket. It seems lazy at first glance (you think why not use two hands!) but in reality they are preventing a path for the current to go across your chest. If they slip and hit an energized component and their other hand is on a metal surface the current will travel through your body. You really don't want to test things by sticking your hands into a tank that could potentially have electrical issues.
With that being said you should only be reading a few mV. Anything over a volt would be suspect to me. Especially 20v+ readings. It is possible that while your meter reads fine at higher voltages it could be out of tolerance on the lower end. I deal with calibration of electrical equipment daily and this is a fairly common occurrence even on higher end equipment.
I did test my tank and was getting <200mV with my Fluval 406 running (heater was off). If you haven't already, I'd suggest reading through the post I linked earlier, it explains ground probes and GFCI's in great detail and in a variety of situations.
It is possible that your tester is showing the outlet is grounded, perhaps to the box, but not physically tied back to your ground bar in your panel. The outdoor rods are 8 foot rods that are hammered down into the ground. In my area, two 8' ground rods are required, in addition to crossing your water meter (uses water pipes as ground).
With that being said you should only be reading a few mV. Anything over a volt would be suspect to me. Especially 20v+ readings. It is possible that while your meter reads fine at higher voltages it could be out of tolerance on the lower end. I deal with calibration of electrical equipment daily and this is a fairly common occurrence even on higher end equipment.
I did test my tank and was getting <200mV with my Fluval 406 running (heater was off). If you haven't already, I'd suggest reading through the post I linked earlier, it explains ground probes and GFCI's in great detail and in a variety of situations.
It is possible that your tester is showing the outlet is grounded, perhaps to the box, but not physically tied back to your ground bar in your panel. The outdoor rods are 8 foot rods that are hammered down into the ground. In my area, two 8' ground rods are required, in addition to crossing your water meter (uses water pipes as ground).
Gregcoyote
Aquarium Advice Addict
meegosh said:
We have the same electrical code. I have to bond electronics on towers. Your advice is spot on.
Yeah, I know something is fishy.
I can't find the culprit. I've been leaving things off for 1 day at a time to see if I can get consistent readings of around 1 volt. It is inconsistent in that sometimes it will be 1 volt and sometimes it will be 20 volts. I think something is screwy some of the time but not all of the time. Yesterday was my reactor pump and I've been getting readings of 17+ all day yesterday so I don't think that is it. Today I'm leaving my skimmer pump off and testing.
So what you're saying is my outlet may be grounded but not tied to the ground? I don't see any rods outside of the house (where might they be located?).
You're also saying 20 volts isn't normal? Saltwater has a lot more equipment than freshwater (if it matters).
I'm going to try to get my hands on another tester. I really don't want to BUY a different one but I will if I have to.
I can't find the culprit. I've been leaving things off for 1 day at a time to see if I can get consistent readings of around 1 volt. It is inconsistent in that sometimes it will be 1 volt and sometimes it will be 20 volts. I think something is screwy some of the time but not all of the time. Yesterday was my reactor pump and I've been getting readings of 17+ all day yesterday so I don't think that is it. Today I'm leaving my skimmer pump off and testing.
So what you're saying is my outlet may be grounded but not tied to the ground? I don't see any rods outside of the house (where might they be located?).
You're also saying 20 volts isn't normal? Saltwater has a lot more equipment than freshwater (if it matters).
I'm going to try to get my hands on another tester. I really don't want to BUY a different one but I will if I have to.
Gregcoyote
Aquarium Advice Addict
scottayy said:
Saltwater is FAR more conductive than fresh water is. Most building code requires a ground rod in most areas, but I have seen electricians that just tie into the cold water supply line. Not perfect but better than nothing. If your electrical panel isn't tied into a good ground, it is a dangerous situation. But I cannot believe it isn't.
Yeah. I'm just going to hire an electrician to come out and investigate my setup. Fish tanks might not be his expertise but I bet he can tell me where the volts are coming from and if I'm properly grounded and safe.
I'll let everyone know what he says.
I'll let everyone know what he says.
I tested my 4 gallon that just finished cycling. It only has a heater and a small 98gph pump.
Both on - 35.6 volts
pump off, heater on - 14.4 volts
pump on, heater off - 35.6 volts
both off - 7.1 volts
power strip off - 1.2 volts
Officially think my meter is jacked up. Wouldn't I feel 35.6 volts when i stick my hand in? And this is more reading than in my 55.
Both on - 35.6 volts
pump off, heater on - 14.4 volts
pump on, heater off - 35.6 volts
both off - 7.1 volts
power strip off - 1.2 volts
Officially think my meter is jacked up. Wouldn't I feel 35.6 volts when i stick my hand in? And this is more reading than in my 55.
kdpuffer
Aquarium Advice Addict
Just so your aware, a ground rod is in the ground and is installed during construction so the wire and rod will not be visible. Also depending on the geological makeup of the ground they may use ground plates instead which are also buried. As far as using the water pipe supplying the house, in Canada our electrical code requires we use that as the ground if the pipe is metal. It would make for a much better ground as it can be miles long. I am an electrician btw. I agree that your meter is suspect and could be giving false readings. I do think having an electrician come in is a good idea cause he can determine if your ground/bond is continuous.
You could also chase the bare copper out of your panel and see if it goes to a ground rod(s). Most are not completely hammered down and a few inches-foot are visible with the bare copper tied to it. If it was new construction it may be buried though but should still be able to chase it out of your panel.
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