GFCI confusion....

[jandree22]

Okay, so this might be a confusing post, so I apologize in advance. Today when i reached in my tank I got the trademark tingling/stinging sensation that tells me there's loose voltage in the water, however it was only at the site of cuts/scratches in my skin, and the rest of my hand was completely fine. I've been shocked REALLY bad before in my 20gal where my whole arm got tingly and paralyzed, so I know what 'bad' is, and this isnt bad.

Anywho, I did some quick research and found two devices, grounding probes and GFCI's. Well, the LFS's around here were closed cause it was after 5 on easter sunday, but I did make a trip to walmart and I got 2 GFCI's(each to take half the load). I hooked the first one up to a power strip that was seemingly causing some of the voltage in my tank, and it is still powering everything. Now, long story short, the instructions for the GFCI are really ambiguous, so just tell it to me straight, if it's powering the stuff there's not enough voltage to trip it, right?

I'm pretty sure I'm still gonna invest in a grounding probe to remove the rest of the voltage, but at least now my life should be protected.

 

[hdtran]

A grounding probe will make sure your tank voltage is the same as ground voltage.

A GFCI will make sure your appliances have the same amount of current going out the 'Hot' wire as returning on the 'Neutral' wire, but does nothing about the electrical potential in the tank.

Current is what kills you. The GFCI protects you from becoming a current path, because it trips its own circuit breaker if more electricity goes out than comes back in (or vice versa).

Hope I've muddied things up for you...

 

[Anonymous]

Hey.. I LIKE making ground.. gets me all tingly! 8)

Jandree, the really good ones are the ones that make you feel like Godzilla just slammed your sorry arse into the ground and yanked it back up again and then e v e r y t h i n g goes into this tunnel, all black 'round the sides! Thos are the really good ones.

Me likey tingle.

 

[Anonymous]

Heh.. you know it's late when instead of editing yourself you QUOTE yourself. With no delete function to boot. :roll:

bash 2.05b# man hosed

Sorry mate, you're on your own!

bash 2.05b# man quote

Shut up!

bash 2.05#b man edit

What did I just tell you??

bash 2.05b# ?

Yeah, you need help alright. Now shut UP!

 

[Anonymous]

if it's powering the stuff there's not enough voltage to trip it, right?

Hmmm... odd question. The GFCI is not like a circuit breaker or fuse which overwhelmed with too much current will trip. So the answer is no, I guess.

What it does is detect a leak of power not going where its supposed to go. I'm sure electricians will consider that a real mangle, but that's the idea.

 

[Anonymous]

Well, where's that louey when we need him, eh? I hear he's a real electrician.

 

[c0yote]

Are you sure it's stray current? Might it be an allergic reaction (you mentioned cuts/scratches) to toxins from something (zoo's, etc)? Fraggin' anything?

 

[jandree22]

it MAY be, but I swear I notices a reduction in the sensation when I unplugged certain things. Havn't fragged anything lately, no zoos

 

[Anonymous]

The GFCI will trip when there is a difference in the outgoing and incoming voltages. By nature of that fact alone, you know its not the GFCI's fault for not tripping when theres no auxilary path to the ground. In other words, there may be a slight leak of power from one of your devices in the water; the fact is, without a ground probe there really is no where for that voltage to go anywhere fast, except to slowly conduct out through semi-conductible materials, like plastic. All this is probably either beneath the GFCI's notice, or it is occuring so regularly that it is perceived as a constant, stable input and output by the GFCI.

Get yourself a ground probe, make sure the outlet youre plugging stuff into has three prongs and the green wire on the inside, and youll never have voltage problems again!

Also, I want to say that though I certainly dont understand it or the properties involved, all electrical devices "broadcast" or exude a type of electro-magnetic field. Water, particularly saltwater with high mineral contents (calcium is the biggy here) may actually be reacting to this sort of "electrical environment" thats caused by the basically unblockable fields of electro-magnetism...
Just tossin' in my brain-shavings...

 

[Kevin1000]

For whats its worth - Our electrician has informed me that there is no way that you could feel any "stray electricity" generated by the electromagnetic fields of any device you have in your tank. He has confirmed that a ground probe may capture the minute amount of electricity generated by these devices. He also indicated that a ground probe should never viewed as a device to save your life in the event that your hand is in the tank and there is a major problem - only a GFI will save your bacon.

 

[Anonymous]

Not even if that "stray current" finds its way to ground through you?

 

[Kevin1000]

I assume the stray current could be grounded through you but the point the electrician was making was that it takes a fair amount of electricity before a human can notice it. In his opinion it is impossible for any of the aquarium devices to generate enough stray voltage for a person to feel it.

 

[Anonymous]

Ah, well then, on that point I must disagree with him. Only speaking from personal experience here, can't say what the source was other than devices like powerheads. When it was stuff like broken heaters there was never any doubt in my mind that it was electricity running through my body.. hrm..

 

[Kevin1000]

Glad your OK - I would not put broken heater in the category of "stray voltage" - more like electrocution.

 

[Anonymous]

Hee.. that's what it felt like!


BBZZZZTTTZZZTTTZZZTTT!!!!

 

[kim]

The current being felt is almost certainly caused by "induced" voltages. No currents are leaking from your pumps etc. (and hence the GFCI will not trip) -but electromagnetic fields are harder to contain.

These fields can cause flows of current themselves - not leakages, just "sympathetic" flows of charged particles. Quite different from the cracked heater syndrome...that is a leak !

kim