electrical problems... need advice ASAP

[spudz11]

Hi all,

So even though many of you disagree with in a previous post for having a 50gal, please just accept it for now and help me fix a real big problem.

I redid the whole aquarium, put in a dual digital thermometer that was originally made for registering computer temperatures. Runs off of 12V, I have an A/C to 12V DC adapter that I'm running it from. I also added some new substrate (the type that comes in a dried brick, and you soak in water to expand).

I bought an Exo-terra UTH, the Rainforest Medium model. I do have a rheostat to run this from, but that aside, I am not using it yet. The UTH is installed, needless to say, under the tank, on the bottom surface of the glass.

The big problem is when either the UTH or the thermometer is plugged in, there is some kind of electrical leak through the tank. What happens is that when either of these items is plugged in the wall outlet, if I rub the snake's back gently, I can feel a buzzing :eek: . Its not a feeling of a shock, or a jolt type of feeling, its a subtle buzzing feeling. When these items are not plugged in, the buzzing feeling goes away when touching him. I had someone else confirm this 'feeling' too, albeit subtle, it is obvious enough to raise concern.

So I figured my house has a faulty ground. Although, both the thermometer and UTH use a two pronged plug (one bigger and one smaller prong), I figured something was faulty in my house's electrical system. I ran an extension cord all the way from my neighbours place... (separate house all together, not a duplex or anything.. they have their own hydro lines) and the same thing!!!!!

I got my multimeter out, and between ME and the substrate, there is a slight voltage change when first contacting, but nothing obvious after that, although the voltage fluctuates between - and + subtly, and this doesn't happen when nothing is plugged in.

Is this some kind of inductance problem?!??! That would have me acting like a capacitor, and explain an initial voltage change, then nothign subsequent. I mean, the UTH isn't even touching anything other than the bottom of the glass, and glass is an incredible insulator.

Also, since the thermometers run from a 12V adapter.... I don't understand how a 12V utility is causing a problem that can be detected like this. I mean, you can lick your fingers and touch a car batter with both hands and not feel a thing.

what is going on?!?!?!?? none of this adds up!?! Given this happens with an extension cord running from my neighbours place, and with two separate items (individually the thermometer and the UTH) I am so confused and clueless as to how to go about fixing this. Call an electrician... call hydro.?!? what am i going to say... come touch my snake?!? HAH

Please if anyone has any suggestions... SHARE SHARE SHARE!

-Brian

[lord jackel]

Ok...some thoughts.


First glass is not a good electrical condutor so I would rule out the UTH.

What type of DC to AC converter are you using? This would be my guess as to where your issue is coming from.

The buzzing you are feeling is pry not electrical (ie. not a current) but a vibration caused by the converter. Does the converter have a fan?

Incidentally, if it was a current going through your snake that you could feel...your snake wouldn't be alive very long as it would literally be cooked, as soon as you touched it to complete the circuit.

Just some ideas.

[spudz11]

Don't totally agree with you... currents can be small and noticable, but not not lethal. This reminds me when i was at a store who's display case with flourescents inside were failing. I leaned on it and got a similar feeling, although that was much stronger, and still not lethal.

firstly this happens with EITHER the thermometer, OR the UTH... I have unplugged everything but the UTH... i can feel it, and i have unplugged everythign but the thermometer... and I can feel it, albeit not as much as when the UTH is plugged in, on its own or at the same time.

not vibration, guratantee... AC adapter is a cube type sitting in the wall socket... UTH doesn't have an adapter, just a plug.

needless to say, nothign except for the lighting and ceramic heater i have are plugged in and being used now... they don't cause any problems

-Brian

[lord jackel]

Don't totally agree with you... currents can be small and noticable, but not not lethal. This reminds me when i was at a store who's display case with flourescents inside were failing. I leaned on it and got a similar feeling, although that was much stronger, and still not lethal.

-Brian

More then likely you were grounded (rubber soles on your shoes)...had you been barefoot standing on a wet substrate (like your snake) you would have grounded yourself and got the crap shocked out of you.

Anyway...Sorry I didn't catch your other facts the first time so it is something different. Is your substrate wet? Only other ideas is maybe you are pinching one of the wires under the tank and getting a short that way.

Other than this I am out of ideas without seeing it....sorry I couldn't help

[spudz11]

Thanks L.J., I've removed the thermometer all together now!

i've tried being bare foot (albeit not wet substrate under me) but i have multimetered a direct ground to substrate. Same as before... a jump in current (0.6V) at first, then it is just a noisy signal +0.1V to -0.1V or so afterwards... but when the UTH is not plugged in, the noisy signal is only about +/- 0.03V.

So, it does seem like something is going on... just don't know what.

I figure perhaps the UTH is defective, it is a 2 prong, perhaps the big/small prong were switched internally... or its ground protection is just mucked anyways...and consequently the thermometer AC adapter didn't have a small/big prong... only 2 small prongs... maybe that adapter just doesn't have ground protection?!

Appreciate the suggestions.. please anyone CHIME IN WITH IDEAS... needless to say, i will be exchanging the UTH tomorrow.

-Brian

[nebby3103]

...needless to say, i will be exchanging the UTH tomorrow.

I mean no disrespect, and this is just my opinion, but it seems like you've put WAY, WAY, WAY too much thought into this :eek: I own one of the Exo Terra UTHs and it works wonderfully. If it didn't I would just drop $20 on a new one. If I were to suspect my thermometer was broken, I would drop a couple bucks on a new one of those as well. If the pursuit of the answer thrills you, go for it. I wouldn't go so far as to call and electrician. Buy new stuff, see what happens. Go from there.



P.S. I also know virtually nothing about electricity...

[spudz11]

Ya well since 2 separate things happen to be giving a similar problem, you have to look at what they have in common: the AC power.

Yes I'm searching for an answer, because there is no obvious reason why this should be acting like it is. I do have a good knowledge of how electricity works, i built 250,000 volt tesla coil for fun a few years ago, and electronics are a general hobby of mine.. hence already owning a multimeter.

Of course I'm going to exchange the UTH tomorrow... but i bet you it will do the same thing since its not only the UTH giving problems. Time will tell i guess. but i need a warm snake, and i'm out of ideas if getting a new product doesn't fix it.

-Brian

[dr del]

Hi,


Well since I am in the U.K. and we have a different setup I won't try and help with the electrical issues.

But, if you still want some advice I'd say go for a "non-expensive" accurite, new heatmat, and try and track down the problem using a dummy setup that does not include your snake in it so you can potter to your hearts content.

That way you have all the time in the world to solve the puzzle without compromising the snakes wellbeing by constantly fiddling with her environment.

Is there a change in potential between the ends of the tank? do you feel the tingle from anything else in the tank ? ( just wondering if its the feel of her scales you are experiencing opposed to dc. )

A few ideas that just occured;

Yes glass is a good insulator but if dampness was leaking through the lower seal from the damp substrate it would allow conduction.

If you use an accurite then you only have battery juice to worry about and it will be far more reliable in the tanks conditions.



dr del

[nebby3103]

I do have a good knowledge of how electricity works, i built 250,000 volt tesla coil for fun a few years ago, and electronics are a general hobby of mine.. hence already owning a multimeter.

I thought that may be the case. God speed.

[kavmon]

get rid of the 12 volt thermometer!


here in the us volts vary a bit in homes. if you put your meter into wall outlets, the volts will vary a bit.


12 volt dc is direct current, this may be causing some of ther problems.

try a battery operated thermometer.

try a new heat pad.

on 120 volt circuits, it doesn't matter which prong is the big one. here in the us, almost everything can run on either polarity. in the old days it mattered.


vaughn