Backyard Aquaponics
A place to discuss aquaponics

Okay a question for anyone electrically minded.

Im pretty happy with wiring things up and have no issues here have been doing it for many many years, but I have noticed that if Im not wearing shoes, I get a very light tingling in any open cuts or sores that are placed in the water tanks, now I know this is caused from the fact that Im becoming an earth circuit into the tanks water system, why would I become an earth circuit, do you think its becuase of static electricity build up from the flow of water through the plastic piping or something else, it cant be a leak in the pumps otherwise they would simply short out, should I place a stainless steel strap into the tanks to provide a permanent earth circuit

Thoughts

If it is tingling just on open sores ,I would suggest it is more likely just the acidic / other nature of the water.
First test would be , remove ALL power to pumps etc ,, then see if you still get that tingling.

Unlikely to be "static".
Probably an early warning sign that there is an insulation breakdown somewhere.
It would be prudent to "megga" the insulation on your pumps, if you don't have access to an insulation tester, ask an electrician or maybe replace the pumps.

Never new there was such a thing as an insulation tester. Do you know how they work

When you have a steel cased appliance the earth lead is connected to the inside of the casing so how could you get an insulation leak without tripping a circuit breaker

Definitely a problem for an electrician....

I have heard of a couple of people having similar problems in the past and it wasn;t the pump. I asked electrician friends and electrical engineers about it and it's a problem with the wiring in the house, a poor main earth, or floating point fault or something. Their suggestion was to get a sparky to look into it...

From my limited knowledge, circuit breakers only trips when it detects current draw above what the breaker is rated for... Most domestic breakers installed are rated to 16A... So I believe in short, the circuit breaker will not trip on detection of a small leakage current that only gives you a tingling feeling... In fact, I believe it could give you a big zap and still not trip...

That's where the RCD comes in... Not sure about the exact rules, but most new houses all the circuits will need to be wired to the RCDs. I think with the exception of possibly the oven that does not need to be... but the AS/NZS 3000 will be able to provide better up-to-date rules... or check with a well-read sparky...

So really if you have an old house with old wiring... do get a sparky to install RCDs soon... may not solve your issue but what it means is that if the leakage is more than the threshold (usually 30mA), it will trip and disconnect the circuit...

RCD's ? are they like GFCI ground fault circuit interupters?
Anyway swap the pump out with your spare and see if it goes away.
Prolly should be looking for a spare anyway if you don't have one yet. my bet is you'll need one soon. An electrican like scotty said can meg the circuit then the motor seperately to determine if the problem is in the cirucit or the motor. Damp rusty wire nuts or rats/cats chewing the wire may be problem in circuit but most likely the pump. I had a mag drive fountain pump that overheated swoll up and cracked still ran but I got a little charge from the water. There are GFCI recepticals (bathroom, Kitchen) and breakers, as well as corded inline types that are required on all extention cords in most industrial plants now.
Warning don't let him meg while the pump is in the water, it's like fishing with an old crank telephone! It will kill the fish!

Yep, I would suggest disconnecting all electrical things to the system and then check again to see if you still get tingling. If you salt your system, that might cause a bit of a tingle in damaged skin like the acid comment though I wouldn't expect a system that is functioning with live fish to be acidic enough to sting skin.

Any sort of small electrical tingling sounds like a bad sign and it would be best to get all the electrical stuff checked out asap cause a real problem could quickly get worse and become a dangerous situation.

simso,

Are you using a ground fault plug or device? If not, get one. That tingling might turn into electrocution. If you have a ground fault device make sure it works properly. If you have ground fault device and it works properly, the problem is not likely electrical at all.

m

I had the same thing happen to me when i built my big plastic lined, metal framed tank.

I had pinched the pump power lead between the shed and the framework, and whenever I was touching the water and the frame at the same time I got a BIG tingle - found the problem pretty quickly

I have a pump that leaks a bit.
A poorly designed (cheap) pump, can leak into the water via capacitance, hence a small tingling.
BUT water (despite what ppl say) is not a great conductor, not when compared to copper.
Bare wires in water could well kill you, but bared wires in a closed loop circuit, will only leak off some current to you, preferring to send most current through the wires. It could be this too.
It could be acidity of the water, however the skin is a half decent insulator, so cuts would make a tiny leak noticeable.

Before installing an RCD (residual current device), locate the fault. An RCD is a great safety feature, and measures the current in the active wire and compares it to that in the neutral, (hence an earth leakage detector). if they're not the same, then it is assumed the earth is carrying current, which could be through your body, and shuts down. However if you don't find the problem first, your system will 'randomly' shut off, and be the demise of your fish.
Be Very careful. Switch off all tank power before climbing in.
If you have access to a megger, use that to test. I have heard of the devices, but am unfamiliar with them. To most sparkies they're a standard tool of the trade.

IMHO, RCDs are best not used on freezers or AP systems, due to the damage a small fault can cause to the system. However this opinion is not widely held anymore. If you don't use an RCD, ALWAYS shut off power before coming in contact with the water. Wear gumboots. Do not touch the water and the steel cage of you IBC at the same time (That's sure to get a tickle in my system with that dodgy pump (which I only use in an emergency))
Furthermore be aware that if you don't use an RCD, then you are taking a risk, always remember this, or I'll remind you at your funeral

the rules in WA are = any time a house is sold you must have two fitted if not there already and any time a house is rented out there must be Two fitted if not there already
and ALL new house are supposed to have them

pretty cheap insurance at $200 -$300 bucks fitted
CHeers
pete

Thanks folks, our house is about 8 years old, it has the rcd built in, ask me I know, have drilled into the house walls a few times only to suddenly have no power, bloody electrical wires getting in the path of my drill they should know they need to move.

Either way will start doing some fault finding today, I have 3 pumps in my two tanks, so it could be any or none. Two of the pumps are complete stainless steel exteriors so shouldnt be them.

SS ones are probley the one

Check that the active is wired to the correct terminal in your leads,(and pumps) sounds like you might have an earth fault.
Find the house copper earth stake that is driven into the ground( usually near the meter box on the wall) and check that the earth wire is still connected.