where to put ground probe...?
 

i have a grounding probe in my tank that is in the sump... i just got a flasher wrasse and i want to lessen the odds that it might jump out... will it be better and advantageous to have the grounding prode in the main tank compared to being in the sump...?

I believe the grounding probe should be near the electrical equipment, such as the heater and pumps.

I don't understand the connection between your wrasse and the grounding probe.

Is the wrasse in the sump? I've never used a ground probe, you critical are they?

[QUOTE][i]<a href=showthread.php?s=&postid=11573359#post11573359 target=_blank>Originally posted</a> by pjf [/i]
[B]I believe the grounding probe should be near the electrical equipment, such as the heater and pumps.

I don't understand the connection between your wrasse and the grounding probe. [/B][/QUOTE]

i'm just trying to minimize all the possibilities of why the wrasse might jump... i was thinking that there is a chance that stray voltages can make the fish jump...

It is far more likely that water quality issues and stress from other fish in the tank will make the fish jump than stray voltage. That said, I have my probe in the sump where most of the equipment is.

I'm not an electrician or a physicist, so take this thread with a heavy grain of salt. I guess I've always assumed it doesn't much matter where you put the grounding probe -- if there's current in your tank, it will find it. Maybe that's not right. I thought that current looks for the easiest path to ground. So long as the point where the current enters the water and point where the probe is wet, there will be dissolved materials in the water between the points sufficient to make the current go in that direction.

I suppose there may be circumstances in which current flows in a substantially direct path between two points in an adquarium without diveriting. Tough to imagine, given all the flow and and potential for movement in the aquarium. I suppose if that's the case the soundest place to put the probe is close to where you'd put your hand in the water, since it seems (to my very uneducated mind) that it's unlikely the current would use you to go to ground if it didn't use the probe.

[QUOTE][i]<a href=showthread.php?s=&postid=11573375#post11573375 target=_blank>Originally posted</a> by FL.Joe [/i]
[B]Is the wrasse in the sump? I've never used a ground probe, you critical are they? [/B][/QUOTE]

My understanding is that a grounding probe will make it more likely (though I guess not ensure) that if there's current in your tank, some of it will be diverted to ground, tripping your GFI.

Usually, if there is current in the tank coming from one of your devices plugged into a GFI, it should trip the GFI. The current will leave the device, but not return through the neutral wire, so the GFI will trip.

There are scenarios, however, in which current may be present in your tank, but also may find its way back to devices on your GFI, never creating an inbalance that trips the GFI. Probably not very likely scenarios, but then safety equipment is not just for the likely scenarios. In this circumstance, a grounding probe should help make it so that some of the current goes to ground, opening your GFI device by creating a current imbalance.

My understanding is that the GFCI is only there for sudden changes in current. The grounding probe serves a completely different purpose which is pulling stray current from the water.

With that in mind... I was once told that it's OK to just keep the probe in the sump. The reason was that the water in your tank and sump are all connected so keeping the probe in the sump works....

IMO any measurable voltage above ground in a tank is dangerous and implies mis-functioning, ungrounded equipment. If you detect such a thing (e.g. with a good multimeter), I recommend unplugging one device at a time until you find the source, and then replacing that equipment immediately.

Stray voltage is effectively indicative of an exposed conductor somewhere. Copper, anyone?

Dan

Uh ohhhh ... another ground probe thread :)

[QUOTE][i]<a href=showthread.php?s=&postid=11576951#post11576951 target=_blank>Originally posted</a> by RandyStacyE [/i]
[B]Uh ohhhh ... another ground probe thread :) [/B][/QUOTE]

:lol:

They're not as fun as the old zeovit or the BB vs. DSB threads were.

[QUOTE][i]<a href=showthread.php?s=&postid=11576897#post11576897 target=_blank>Originally posted</a> by bdare [/i]
[B]My understanding is that the GFCI is only there for sudden changes in current. The grounding probe serves a completely different purpose which is pulling stray current from the water.
[/B][/QUOTE]

GFI will trip if the current coming in on the neutral end does not match what's going out on the hot end.

This will usually happen if something is leaking current into your tank, but not *always.*

For example, if you had an exposed hot wire in your tank and also an exposed neutral, and the current were traveling from one to the other, the GFI would not detect a ground fault, because the amount going out would equal the amount going in. Nevertheless, if you stuck your hand in, you'd give that stray current a new path to ground.

This is where a grounding probe comes in. It can act as your hand and trips GFI before you do.

Put it in the trash.