voltage with no power

[jbomar3771]

I turn everything off. Nothing in the tank has power going to it but when i put a meter on it i get 15 volts. With everything plugged in i get 30 volts. Why would it show 15 volts with no power?

[shortcake]

I'm not an electrician but just turning things off doesn't necessarily mean its not still drawing energy. That's why it is suggested, to help save money, that you unplug whatever you can when not in use, so it doesn't continue to draw electricity. For example, chargers may still draw energy when not in use in order to detect feedback.

[jbomar3771]

Yes. Thats what i did. I completely unplugged everything

[shortcake]

hmmm then I'm not too sure, perhaps an issue with the meter then...

[karimwassef]

what are you measuring and how are you measuring it?

The physical implementation of the measurement matters too (length of wire), grounding, etc...

[jbomar3771]

Like they do on YouTube. I put the ground in the ground on a wall outlet and the red in the water. I get the right voltage when i test the socket.

[BeanAnimal]

If everything is unplugged, then there is no current path. The reading is erroneous, and a result the meter's design. It is showing a fixed floating voltage in the absence of ANY voltage and instead of floating or showing open, it shows a fixed voltage as the result of capacitance.

If the tank IS grounded, then you are reading the difference in potential between the two grounds. Without measuring current flow through the circuit, the reading is meaningless and again likely due to the design of the meter. If you did try to measure the current flow that is causing the meter to read 15 volts between the ground and unplugged, grounded tank, there is likely not enough to measure.

Side note: You should make use of GFCI protection for you aquarium and anything near it.

[alton]

Make sure you are wearing INSULATED GLOVES AND SAFETY GLASSES and take a measurement between the grounded prong (large slot on receptacle) and the grounding prong (u shaped) and see if you have any voltage? And then between the grounding prong and the ungrounded prong (small slot)? if you have a poor grounding means at your service, your meter maybe using your tank as a grounding means. Also did you have your lights turned off? Open lamps to water will also add stray voltage.

[A1t2o]

You could always do what I did. Touch the ground and stick the other hand in the tank, you will feel if there is an issue. Then continue the same thing until the while unplugging one cord at a time until the shock goes away. I did this when my lights had built up too much salt and was shorting around 80-120V to the tank depending on when I measured in the process. (I think it got a little wet while I moved stuff around and made a better connection to the water.)

BTW, this is not recommended and my chest hurt by the time I was done. I also have a very high tolerance to electricity, I can touch 120VAC and just feel a buzz while many others will feel the jolt up their arm. With this being in water though, you feel it a lot more so be careful. I am mainly pointing out that salt build-up and water splash on your lights can cause stray voltage if there is any way for the light frame to come in contact with any portion of the top or interior of the tank.

[etnorias1024]

A friend of mine had this exact same issue - 15v with absolutely nothing plugged into the tank. We started looking into it and went through numerous tests: multiple multi-meters, etc. We even went as far as bypassing the house ground and planting a copper rod into the soil outside his house to verify that we actually had a good "ground." We could never

We never found a conclusive answer but I did find some research on the web that is looking into power generation from the oceans. There is some but not a lot of information it (I assume that scientists don't want to give up a potential "cash cow.")

Everybody knows that static electricity is produced by stuff moving across stuff and it tends to build up until it can discharge. Triboelectric (http://www.explainthatstuff.com/how-static-electricity-works.html) effect (about 1/2 way down the page.

Saltwater has a lot of charged particles in it and we force it through pvc and silicone tubes which, I think, is causing a measurable static charge to build up in the water.

Additional sites: Electricity produced when fresh water mixes with saltwater - http://physicsbuzz.physicscentral.com/2009/07/electricity-from-salty-water.html

It's possible I'm wrong. I'd be happy to see if anyone else has more information on this.

[jbomar3771]

I did have the lights on. I know gfci is the way to go but do you guys worry about that thing tripping while your gone and shutting everything off?

[alton]

I did have the lights on. I know gfci is the way to go but do you guys worry about that thing tripping while your gone and shutting everything off?

I had a tank once that had 9 volts with the power compacts on, turn them off and check again

[karimwassef]

Sources of energy:

Battery backup (outside or inside product)
UPS
large capacitance
Localized EMI (I had a bug zapper that caused havoc)

Faulty meter is likely.. Get another

[Fish Keeper82]

I had a tank once that had 9 volts with the power compacts on, turn them off and check again

+1

Induced voltage from lights is highly likely (depending on your type of lights).

[jbomar3771]

I have 3 ai sols and 2 t5s

[Fish Keeper82]

I have 3 ai sols and 2 t5s

The T5's i suspect are what you were seeing. Some of the output voltages of the secondary side of ballasts to fire them up actually put out about 600 volts at the sockets. Higher voltages = more induced voltage. I wouldnt be conceren with it. As stated before make sure all your tank circuits are GFCI protected.

[atreis]

I did have the lights on. I know gfci is the way to go but do you guys worry about that thing tripping while your gone and shutting everything off?

No - if it trips there's almost always a reason, which means it's doing its job. My house has them on every circuit and I'll find one tripped at random maybe once every 2-3 years.

Ground-Fault circuit breakers seem to trip a lot more often (pretty much any time there's a very brief power outage due to a passing storm). I ended up removing the one I had on the circuit with the tank.

[karimwassef]

Yes. Nuisance GFCI trips while you're away are a concern, but it's not worth the risk to your life to avoid it.

GFCI is about protecting you, not the fish or the equipment. It's not 'optional'.

If it trips, it's likely due to equipment that was designed without sufficient margin on leakage current & you would want to address that issue anyway.

It won't trip because of high current - that's what a breaker is for. A lightning storm won't trip it.

[Breadman03]

I did have the lights on. I know gfci is the way to go but do you guys worry about that thing tripping while your gone and shutting everything off?


Two circuits with some heat and circulation on each, plus my Apex to alert me if something is wrong means minimal worry for me.

[karimwassef]

Also, I have a UPS on a critical circuit and I'm also looking to add low voltage battery power for critical pumps.

[BeanAnimal]

You could always do what I did. Touch the ground and stick the other hand in the tank, you will feel if there is an issue. Then continue the same thing until the while unplugging one cord at a time until the shock goes away. I did this when my lights had built up too much salt and was shorting around 80-120V to the tank depending on when I measured in the process. (I think it got a little wet while I moved stuff around and made a better connection to the water.)

BTW, this is not recommended and my chest hurt by the time I was done. I also have a very high tolerance to electricity, I can touch 120VAC and just feel a buzz while many others will feel the jolt up their arm. With this being in water though, you feel it a lot more so be careful. I am mainly pointing out that salt build-up and water splash on your lights can cause stray voltage if there is any way for the light frame to come in contact with any portion of the top or interior of the tank.

Not at all smart. Your "tolerance" to "voltage" is a figment of your imagination and you are lucky you are not dead. We are all made the same, our bodies have varying resistance based on numerous factors from diet and hydration to skin lotions and mood and the clothes you are wearing or perspiration and body temperature.

[BeanAnimal]

I did have the lights on. I know gfci is the way to go but do you guys worry about that thing tripping while your gone and shutting everything off?


Use multiple gfcis so that a fault or nuisance trip does not bring down the entire tank.