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Electricity Issue need help! *ZAP*


uwwmatt

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Quick background: Last night my Reef Keeper failed. I have figured out the temp probe is shot so none of my heating or cooling can be controlled. This meant I have to rely on the crappy thermostats in the heaters to keep the temp stable.

 

I was reaching into the back chamber to adjust one of the heaters (one hand in the tank water) when my face came in contact with the metal cable that hangs my light from the ceiling. I felt a sharp burning where the skin of my face contacted the cable.

 

I figured something in my tank must be leaking electricity into the water and when I touch the metal cord it grounds it somehow giving me a shock. This is pretty stupid on my part, but I didn't have voltage measuring tool, so I went one by one unplugging things and touching the cable with my wrist (wasn't strong enough to feel with my hands) and sticking my other finger in the tank water. It got sort of difficult to judge because it seemed sometimes one thing would cause that sensation, and then I would try it again and nothing. (Plus it was getting really late and I just kept thinking how I was going to get electrocuted like a jackass :eek:) Last night before I went to bed I had come to the conclusion that it must be the return pump, so today I planned on swapping it out.

 

While at work I got to thinking maybe the problem was not in my tank, but the light itself. I have had issues with it blowing t5 bulbs. So I unplugged everything again except the T5 lights and gave it the zap test again. Sure enough with nothing else plugged in I got the little tingle. I then unplugged the cord for the t5 and plugged in the MH and fired it up and no tingle.

 

What I don't understand is why would my hand need to be in the tank to cause me to get a shock? If electricity is running through that cable shouldn't just me touching the cable alone be enough to cause that sensation? Is there still something I am overlooking, other than the fact that people shouldn't intentionally shock them selves to test their hypotheses.

 

You can see the cables and how the cords are moved in these pictures.

Full_left_FTS.jpg

 

Now with this controller issue and the electricity I feel like my tank is on the verge of a crash...

IMG_0774.jpg

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LOL.. I need you to come test my electric horse fence.

 

It wasn't a shinning moment, but being as I made it past the initial encounter I figured/hoped there wasn't going to be some crazy surge.

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What I don't understand is why would my hand need to be in the tank to cause me to get a shock? If electricity is running through that cable shouldn't just me touching the cable alone be enough to cause that sensation? Is there still something I am overlooking, other than the fact that people shouldn't intentionally shock them selves to test their hypotheses.

This is just a suggestion and would need further testing to confirm.:

 

The carpet/your shoes are insulating you from ground. When you touch only the cable you are like a bird on power line and not shocked (sorry for the cliched analogy). When you touch the tank, even with everything unplugged, there is sufficient potential difference to give you a shock.

 

What is of some concern is that the light fixture is metal and it's chassis should be grounded. Is the light plugged into a grounded socket? If it is and there is a GFCI on the same circuit, the GFCI should trip when you try to turn on the T5s. (Current leak to ground causing a difference in current between the live and neutral - a ground fault).

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This is just a suggestion and would need further testing to confirm.:

 

The carpet/your shoes are insulating you from ground. When you touch only the cable you are like a bird on power line and not shocked (sorry for the cliched analogy). When you touch the tank, even with everything unplugged, there is sufficient potential difference to give you a shock.

 

What is of some concern is that the light fixture is metal and it's chassis should be grounded. Is the light plugged into a grounded socket? If it is and there is a GFCI on the same circuit, the GFCI should trip when you try to turn on the T5s. (Current leak to ground causing a difference in current between the live and neutral - a ground fault).

Thanks for the response

 

 

There are two cords that run from the light to the ballast enclosure in the stand. Then two more cords run out of other end of the ballast and are plugged into outlets. The MH power cord is plugged into one of the outlets associated with my ReefKeeper and the one for the T5s is plugged into one of those Coral Life surge protector/timer deals. That in turn is plugged into my wall. All plugs are three pronged so I assume they are grounded.

 

Could a wire have come free in the light and made it ungrounded? Would that cause the shock? If it is indeed the light causing the problem would touching the wall and the wire at the same time cause a shock?

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Tube lights can generate a charge on the outside of the glass tubes. I know this is crazy. Remember the days when folks use to put small Flourescent tubes on cb radio antenna. Pickle put on next to your electric fence. It will glow with each charge pluse. They would light up whenever you squelched the radio. Kinda the same thing but in reverse. Its more of a constant static charge. High voltage low amperage. Not gonna kill you. But when you factor in the high humidity mixed with salt everything becomes a conductor. So it is plausable that a small micro layer of salt has bridged between the connectors of the tubes, then to the case and cables. This charge is so small that you can only feel it when your grounding yourself in the water. Have you ever turned the shower handle and had a cut in your finger nail area burn. Same thing. I would get a grounding probe into the tank. A good idea any way. I've seen pwr heads allow a ground through them. So yes its still shielded but can ground. Crazy I know but electro magnets can do some spooky stuff.

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Tube lights can generate a charge on the outside of the glass tubes. I know this is crazy. Remember the days when folks use to put small Flourescent tubes on cb radio antenna. Pickle put on next to your electric fence. It will glow with each charge pluse. They would light up whenever you squelched the radio. Kinda the same thing but in reverse. Its more of a constant static charge. High voltage low amperage. Not gonna kill you. But when you factor in the high humidity mixed with salt everything becomes a conductor. So it is plausable that a small micro layer of salt has bridged between the connectors of the tubes, then to the case and cables. This charge is so small that you can only feel it when your grounding yourself in the water. Have you ever turned the shower handle and had a cut in your finger nail area burn. Same thing. I would get a grounding probe into the tank. A good idea any way. I've seen pwr heads allow a ground through them. So yes its still shielded but can ground. Crazy I know but electro magnets can do some spooky stuff.

 

So is this a most likely a normal occurrence? Is it safe to run the T5s without damaging the tank (or my life)?

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So is this a most likely a normal occurrence? Is it safe to run the T5s without damaging the tank (or my life)?

 

 

I'll say this. If it were mine I'd run em. But you have to make that call. My MH shocked me for years w/o the first problem. I'd say that there isnt any stray voltage in the tank. Its just from the light. If it aint touchin it aint leaching into the tank. Keep in mind. Its winter and the air is dry. Static is at its highest levels this time of year. It may go away once the air is a little less dry.

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When in real doubt, get a GFCI plug, and if the difference is enough it will trip, and then you'll know if it's something to worry about.

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here fishy fishy

I had this same problem in my tank not too long ago. I had a voltage meter and tested like crazy. Everything I plugged in made the voltage in the water go up a bit, and I was at 38 volts in the water with everything up and running. I had the same experience with hands int he water and having the light fixture itself bump my face giving me a shock. I was also getting shocks just sticking my hand in the water and some of them were nasty. I could do nothing int he tank unless I unplugged everything. After 2 weeks of trouble shooting, talking to and electrician friend and an electrical engineer, and not being able to resolve anything, I bought a grounding probe.

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When in real doubt, get a GFCI plug, and if the difference is enough it will trip, and then you'll know if it's something to worry about.

Do I just plug the light into the GFCI plug, or do I plug the whole power strip?

 

Something like this?

http://www.amazon.com/Tower-Manufacturing-...6813&sr=8-6

 

Do this. Every tank should have one.

 

I had read a couple posts on these forums that said grounding probes would actually cause problems for the corals. Something about giving the stray current a path through the tank would actually cause them to be shocked more so than without one. Was that just misinformation?

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Hello, I am an electrician and might be able to help you with your issue. The first thing I would like to say is that you do indeed have a potentially life threatening situation. I completely agree with the guy that said get a GFCI and make sure everything in and around your tank is on one. You may need more than one depending on the loads you have. Then check the ground on your light fixture. A good ground will be less than 1 Ohm. Get a multi-meter to check it out.

In order to feel an electrical discharge on your skin it takes about 10 milliamps. 100 milliamps can kill you. The GFCI is designed to sense the fault and trip the circuit before the current flow is sufficient to kill you.

Your skin has about 10,000 ohms of resistance dry, but when you put your hand into the water you decrease the resistance to ground. The tank is a large ground even if you do not have anything in it that is grounded. Some people think that you have to be grounded (to the earth) to get shocked, this is not true. Think about in the winter when you go to get in your car and get zapped by static discharge. You're not grounded, neither is the body of the car, but the car is a big enough ground on it's own that the static charge on your body jumps to it. An easy way to avoid the sting is by touching the metal part if the key with your finger and then touch the key to the lock. the discharge will happen at the end of the key instead of on your skin.

Electrical voltage is referred to as a difference of potential. Your light fixture is at a higher potential then your tank. When you touch them both you become the conductor for the electrons to flow through. If you do something to increase the tanks ground potential like adding a grounding probe the resistance goes down there for the current flow will go up. this is why I would strongly recommend the GFCI and Not recommend a grounding probe for your situation. A grounding probe may be good in other situations, but not this one.

Based on the info you have provided so far, I would feel very secure in saying that your trouble (electrical fault) lies in the ballast for that light. A ballast is typically made up of a transformer and a capacitor. One of these can fail and the lamp still work. I have seen this many times in street lights. Are you able to disassemble the ballast? there could be a shorted wire, or something grounded inside the case. You might be able to fix it if you can find it. I hope this helps, I would be glad to help if you have questions. Please don't kill yourself using your body as a voltage meter!

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Hello, I am an electrician and might be able to help you with your issue. The first thing I would like to say is that you do indeed have a potentially life threatening situation. I completely agree with the guy that said get a GFCI and make sure everything in and around your tank is on one. You may need more than one depending on the loads you have. Then check the ground on your light fixture. A good ground will be less than 1 Ohm. Get a multi-meter to check it out.

In order to feel an electrical discharge on your skin it takes about 10 milliamps. 100 milliamps can kill you. The GFCI is designed to sense the fault and trip the circuit before the current flow is sufficient to kill you.

Your skin has about 10,000 ohms of resistance dry, but when you put your hand into the water you decrease the resistance to ground. The tank is a large ground even if you do not have anything in it that is grounded. Some people think that you have to be grounded (to the earth) to get shocked, this is not true. Think about in the winter when you go to get in your car and get zapped by static discharge. You're not grounded, neither is the body of the car, but the car is a big enough ground on it's own that the static charge on your body jumps to it. An easy way to avoid the sting is by touching the metal part if the key with your finger and then touch the key to the lock. the discharge will happen at the end of the key instead of on your skin.

Electrical voltage is referred to as a difference of potential. Your light fixture is at a higher potential then your tank. When you touch them both you become the conductor for the electrons to flow through. If you do something to increase the tanks ground potential like adding a grounding probe the resistance goes down there for the current flow will go up. this is why I would strongly recommend the GFCI and Not recommend a grounding probe for your situation. A grounding probe may be good in other situations, but not this one.

Based on the info you have provided so far, I would feel very secure in saying that your trouble (electrical fault) lies in the ballast for that light. A ballast is typically made up of a transformer and a capacitor. One of these can fail and the lamp still work. I have seen this many times in street lights. Are you able to disassemble the ballast? there could be a shorted wire, or something grounded inside the case. You might be able to fix it if you can find it. I hope this helps, I would be glad to help if you have questions. Please don't kill yourself using your body as a voltage meter!

 

Thank you for your reply.

 

In your opinion would that GFCI I posted in an earlier reply be sufficient? Would it still be useful if I plug my PC4 (the outlets from my controller) into the GFCI and then the lights into the PC4. Or does the light need to go directly into GFCI?.

 

Would this work for the multimeter?

http://www.amazon.com/Equus-3320-Auto-Rang...0752&sr=8-2

 

Where would I place the sensors to figure out the problem?

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Put your GFCI on the PC4, NOT the otherway around. Otherwise the GFCI may trip just from the electrical noise generated by the PC4's.

 

For now, I would put the GFCI's on all your lighthood power specifically.

 

I wouldn't worry too much about the pumps, as they have a tendency to simply die spectacularly when they do (due to the salt water)... this also goes for heaters.

 

GFCI's arn't cheap, so you may want to just cover what you need for now, first.

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Put your GFCI on the PC4, NOT the otherway around. Otherwise the GFCI may trip just from the electrical noise generated by the PC4's.

 

For now, I would put the GFCI's on all your lighthood power specifically.

 

I wouldn't worry too much about the pumps, as they have a tendency to simply die spectacularly when they do (due to the salt water)... this also goes for heaters.

 

GFCI's arn't cheap, so you may want to just cover what you need for now, first.

 

http://www.amazon.com/Tower-Manufacturing-..._ecc_rvi_cart_1

 

I picked one of these up. I can just leave the T5 unplugged until it arrives because I only felt that shock when that was plugged in. I also ordered that multimeter I posted above.

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Matt, The GFCI you posted should work fine, However I feel that you would be better off changing your outlets to GFCI like this one.

http://www.grainger.com/Grainger/HUBBELL-W...XB82?Pid=search

This is really cheap insurance.

I would say that you should have everything associated with your tank on a GFCI. If you do this and have troubles with the GFCI tripping, that means you have a true ground fault and need to resolve it. My daughter runs a curling iron and a hair dryer at the same time off one GFCI outlet. I doubt your tank equipment is pulling more load than that.

That meter looks like it would be fine for your needs. Be sure to read the manual when you get it. you can damage the meter if you have it set up to read amps and go across the line inadvertently. The black lead will plug into the center port at the bottom of the meter, and the red will plug into the one on the right. (if I can see the picture right. it is kind of blurry) Set the dial to the ACV setting. Connect one lead (doesn't matter which in the situation) to the light, where ever you touched it when you got shocked. and connect the other to a ground prong in an outlet. use an extension cord if you need to. Be sure you learn how to read the display on the meter. Sometimes people see a number like 78.5 and think it is volts, but don't realize the meter auto ranges and shows in the corner that it is on millivolts.

Would you be able to post pics of the equipment? IE the ballast and the cords. You said the ballast has two cords going in and two outlets right? Are both side of the ballast the same or is one for one type of light and the other side for another type? What I am getting at is there is a common troubleshooting technique where you swap the equipment and see if the trouble moves to the other equipment or remains the same this can help us determine where the fault is.

Hope this helps, I will go back and re read the post to see if I missed anything.

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I had read a couple posts on these forums that said grounding probes would actually cause problems for the corals. Something about giving the stray current a path through the tank would actually cause them to be shocked more so than without one. Was that just misinformation?

 

This is not misinformation. Again think of the analogy of the birds on a powerline. Now, I will say, if you want to protect yourself when putting your hands in the tank, you can use it then just in case. You just dont want to keep a path for the current to flow in the event something is leaking - its the current would be harmful.

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Some people think that you have to be grounded (to the earth) to get shocked, this is not true. Think about in the winter when you go to get in your car and get zapped by static discharge. You're not grounded, neither is the body of the car, but the car is a big enough ground on it's own that the static charge on your body jumps to it.

 

:huh: Can you explain your thinking on this? In order for current to flow, its needs a path, say from high potential to low potential. In your example, how are we not grounded? Arent we walking on the earth? Isnt your car's tires sitting on the earth? And why is it if a car is struck by lightning, you are safe in the car? Doesnt the charge dissipate in to the earth?

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Would you be able to post pics of the equipment? IE the ballast and the cords. You said the ballast has two cords going in and two outlets right? Are both side of the ballast the same or is one for one type of light and the other side for another type? What I am getting at is there is a common troubleshooting technique where you swap the equipment and see if the trouble moves to the other equipment or remains the same this can help us determine where the fault is.

Hope this helps, I will go back and re read the post to see if I missed anything.

 

I'll take pictures of everything when I get home from work in an hour.

 

Here is one I took a while ago

IMG_9728.jpg

 

I may have misspoke earlier. I believe (i'll know for sure when I get home). That there is one cord that runs directly from the light controlling the T5s (I think) that I plug in to the wall. Then there is another cord (the white one) That runs from the light to the ballast. Then a black cord runs out of the ballast and is plugged into the wall.

 

Sorry if that is confusing. I haven't really done much with the wiring since I originally set it up 6 months ago.

 

 

 

As for installing the wall outlet you posted, I live in an apartment and don't want them to get pissed at me for messing with the wiring. Not to mention I would have no idea what I was doing. I also don't want to ask the handyman guy for our apartment to do it. I don't think the property manager would appreciate me having a possibly dangerous electrical problem in the apartment. Is it an easy install?

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Now, I will say, if you want to protect yourself when putting your hands in the tank, you can use it then just in case. You just dont want to keep a path for the current to flow in the event something is leaking - its the current would be harmful.

Agreed. A grounding probe is a device for our safety. There is no harm in using one if your equipment is in good order and not leaking current by poor insulation. Where people get it wrong is that they think the grounding probe has somehow fixed the pump or whatever with damaged insulation because they can no longer measure a potential difference. It's a similar type of misunderstanding as all the "I don't understand where all the hair algae/cyano is coming from, my nitrate tests 0" posts. The other thing often overlooked is stray voltage caused by induction but that is topic for another discussion. If you are getting electric shocks from your tank equipment, there is something dangerously wrong.

 

Some people think that you have to be grounded (to the earth) to get shocked, this is not true. Think about in the winter when you go to get in your car and get zapped by static discharge. You're not grounded, neither is the body of the car, but the car is a big enough ground on it's own that the static charge on your body jumps to it. An easy way to avoid the sting is by touching the metal part if the key with your finger and then touch the key to the lock. the discharge will happen at the end of the key instead of on your skin.
:huh: Can you explain your thinking on this? In order for current to flow, its needs a path, say from high potential to low potential. In your example, how are we not grounded? Arent we walking on the earth? Isnt your car's tires sitting on the earth? And why is it if a car is struck by lightning, you are safe in the car? Doesnt the charge dissipate in to the earth?

What he posts is correct. The biggest ground available to us is planet earth, that is not to say other things can not act as grounds. Think about it, the cars tyres are insulating it from planet earth, as your shoes are insulating you. The car is a big enough ground however and there is sufficient potential difference for the static to discharge. If you are in a car and it is struck by lightning, the charge does dissipate in to the earth. The resistance of the car tyres is minute compared to the several hundred or thousand yards of air the lightning has already moved through to strike the car initially. You are safe as the electricity flows over the skin of the car.

I may have misspoke earlier. I believe (i'll know for sure when I get home). That there is one cord that runs directly from the light controlling the T5s (I think) that I plug in to the wall. Then there is another cord (the white one) That runs from the light to the ballast. Then a black cord runs out of the ballast and is plugged into the wall.

That would be normal. +1 for the T5 ballast being the likely culprit.

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:huh: Can you explain your thinking on this? In order for current to flow, its needs a path, say from high potential to low potential. In your example, how are we not grounded? Arent we walking on the earth? Isnt your car's tires sitting on the earth? And why is it if a car is struck by lightning, you are safe in the car? Doesnt the charge dissipate in to the earth?

Yes current needs a path to flow and yes it flows from a source of high potential through a path to low potential. In my example, your body has high potential and the car has low. because it is winter and the air is dry and you just put on your jacket and created a high static charge on your body. Since I wear shoes and they are a fantastic insulator as I walk to my car I am not in direct contact with the earth. and since my car has tires that are made of rubber, another fantastic insulator it is not grounded either. I have high potential the cars low = I get zapped when I touch it. this is how people catch on fire at the gas pump when they get in and out of their car while fueling. check out the videos on youtube.

She created the charge getting in and out of her car. In this particular case she was touching the gas pump handle and that is grounded. If you live in a cold climate you know this also happens when the car is not grounded.

Someone pointed out the bird on the wire concept. while it is true that the bird didn't get zapped because he isn't grounded he did have a difference of potential prior to landing on the wire. As the bird approached the wire it flies through the corona surrounding the wire and he becomes energized and his potential is equalized before he lands on it. People do this also, watch this video

these are 345,000 or more high voltage lines, you will not see birds land on these. the difference of potential is too high and they will get zapped as they approach it. I saw a hawk one time try to land on 138,000 volt lines. I was 70 or 80 yards away the zap was quite loud. The hawk was at least a foot away at point the arc jump to it, and it fell to the earth dead.

Your question about being in a car that gets hit, In this case we differ back to the old adage that electric takes the path of least resistance. you know that the cars body is metal and therefore has a dramatically lower resistance than you. Since your inside of it the electrons flow around you instead of through you. the car is not grounded, but it is easier for the electrons to flow through it and then jump to ground under it rather than flow through the air around the car. The reason lightning can jump through the air is that the air becomes ionized at the instant the arc starts and the air becomes conductive. Watch this video, all they did was open the disconnect switch before they opened the breaker. This was done intentionally as a part of a startup test, but in my industry this is a big NO-NO in any other situation.

.

I do hope I have answered your questions as I am quite tired of typing now.

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Someone pointed out the bird on the wire concept. while it is true that the bird didn't get zapped because he isn't grounded he did have a difference of potential prior to landing on the wire. As the bird approached the wire it flies through the corona surrounding the wire and he becomes energized and his potential is equalized before he lands on it. People do this also, watch this video

The bird on the power line analogy is flawed but it does get across the concept of potential difference in a way everyone can relate to.

 

Cool video.

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The bird on the power line analogy is flawed but it does get across the concept of potential difference in a way everyone can relate to.

 

Cool video.

 

Thanks, I know it is not completely accurate, but I tried. It is hard to explain without getting so deep that I would lose some of the readers and they still wouldn't understand.

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