Can water be energized?

[kwired]

Ever hear of selective hearing ? I must have selective vision. I totally overlooked that it tripped the Main.

I was with you on this, but not from that angle, the EGC of the disposer could be bringing a raised voltage from the grounded service conductor to the vicinity, and unplugging the disposer would disconnect it from the source. Of course if all metal piping is indeed bonded it likely does nothing to unplug the disposer, or it could make things worse depending on what the problem is and what is/is not bonded.


I don't think it tripped the main, I think he still had his unexplained voltage with the main turned off, which is a good indication there is outside voltage coming in from something, and is also complicated by some things not being bonded together.

 

[hurk27]

This is a very clear example that happens with a swimming pool, when the service neutral has a voltage drop it rises above the earth potential, this small voltage rise is now what people feel when trying to get out of a pool that has the hand rails bonded to the service neutral but the concrete of the pool is not bonded which is at the potential of Earth, in this case the copper drain pipe is at the Earth potential and the sink and or cold water pipe is at the potential of the service neutral, like Don said if you took a long wire and stuck a screw driver into the ground away from the service you would most likely see the same voltage between the screw driver and the grounding of the house which is bonded to the service neutral, like you said when you directly measured between the cold water pipe and the copper drain pipe and saw 2.2 volts, this is most likely what you would see on the screw driver to the grounding of the house, it is not the Earth that has a raised voltage but it is the service neutral of the house that has a normal voltage drop that causes the neutral and the grounding of the house to be at an above potential to Earth, and the copper drain pipe is at Earth potential.

2.2 volts is not an unrealistic voltage drop on a neutral, and since you still had this voltage after turning off the main it is most likely coming from the primary neutral since the primary neutral and the secondary neutral are bonded together at the transformer, if you were seeing something above 10 volts then I would be worried as this is a good indication of an open primary neutral somewhere down the road, but 2.2 volts is not that far out.

Put a permanent bond between the copper drain and the cold water pipe and you should be good to go, I would in about a month recheck the voltage between the service grounding and remote Earth to see if it has got any higher, you can expect a few more volts if the load on the primary neutral is increased but you should not see anything up around 10 volts, if it does start getting that high then call your POCO immediately

 

[hurk27]

Ever hear of selective hearing ? I must have selective vision. I totally overlooked that it tripped the Main.

I don't think Charlie was implying that it tripped the main I.E. like in a fault, I think he was meaning that tripping the main in the sense of turning off the main to see if the voltage went away.

 

[DavJ09]

So, the cold water pipe is connected to ground which allows the bridge between the copper drain and cold water pipe to return any stray current to ground?

-- J. Davis (tapatalk!)

 

[ActionDave]

So, the cold water pipe is connected to ground which allows the bridge between the copper drain and cold water pipe to return any stray current to ground?

-- J. Davis (tapatalk!)

It puts the cold water pipe and the drain pipe at the same potential above earth/zero volts.

 

[GoldDigger]

No. The cold water pipe is connected to the utility neutral while the drain is connected to "earth".
The current is going through the earth as an alternative way to get back to its source instead of following the POCO neutral.
As stated earlier, your jumper is not bringing the neutral/ground down to remote earth potential, you are raising the drain pipe and the zone of earth closest to it above the remote earth voltage to match the water pipe.

Note that the bond between the neutral and the house ground electrode system is not bringing the neutral bond point down to remote earth voltage either. Because of this there will be current flowing through the GES also.

Tapatalk!

 

[DavJ09]

No. The cold water pipe is connected to the utility neutral while the drain is connected to "earth".
The current is going through the earth as an alternative way to get back to its source instead of following the POCO neutral.

I understand this.

As stated earlier, your jumper is not bringing the neutral/ground down to remote earth potential, you are raising the drain pipe and the zone of earth closest to it above the remote earth voltage to match the water pipe.

So, if the branched connection of the drain pipe were raised to the level of the bond, then would it eliminate the stray current? Or, from research am I correct I'm saying that it is inevitable to eliminate all stray current in a residential dwelling?

Note that the bond between the neutral and the house ground electrode system is not bringing the neutral bond point down to remote earth voltage either. Because of this there will be current flowing through the GES also.

Is your "GES" an acronym of "ground electrode system" or an acronym for

"generalized electrical susceptibility?"





-- J. Davis (tapatalk!)

 

[GoldDigger]

I understand this.




So, if the branched connection of the drain pipe were raised to the level of the bond, then would it eliminate the stray current? Or, from research am I correct I'm saying that it is inevitable to eliminate all stray current in a residential dwelling?




Is your "GES" an acronym of "ground electrode system" or an acronym for

"generalized electrical susceptibility?"





-- J. Davis (tapatalk!)

Yes, GES is the accepted acronym for Ground Electrode System.
And your problem is not eliminating the stray current, it is eliminating the stray voltage.
By bonding the two pipes together with copper wire you can eliminate the voltage difference because the stray current will go through the copper wire.
It is not possible in general to eliminate all stray voltages in a residential environment, since resistive voltage drop in the neutral from normal currents will cause some voltage offset. But proper practice can reduce the number of paths that stray current can follow and also keep any resulting stray voltages to a minimum.

 

[DavJ09]

Thanks, GoldDigger!

-- J. Davis (tapatalk!)

 

[don_resqcapt19]

...
Note that the bond between the neutral and the house ground electrode system is not bringing the neutral bond point down to remote earth voltage either. ...
Tapatalk!

That is one of most commonly misunderstood parts of grounding...the fact that the connection of earth does not lower the voltage on the conductor that is connected to the earth...the connection to the earth raises the voltage of the earth for a small area very close to the earth connection (grounding electrode). It does nothing to change the potential of the conductor that is connected to the earth as referenced to "remote earth".

This is exactly why a grounding electrode can never be used in place of an Equipment Grounding Conductor.

 

[kwired]

So, if the branched connection of the drain pipe were raised to the level of the bond, then would it eliminate the stray current? Or, from research am I correct I'm saying that it is inevitable to eliminate all stray current in a residential dwelling?

Stray current still flows, the bonding jumper shunts that current around the people using the equipment in question. In the OP incident simple bonding of the two pipes in question is all that is necessary as the users are not in contact with any other grounded objects that are not also bonded to these pipes - everything is at same potential or is an insulator.

Take same situation outdoors or somewhere with other conductive objects that are grounded but not bonded to other objects and you may still be subjected to points of potential. This is why with swimming pools they bond everything conductive together, so that one object in the pool is subjected to elevated voltage above ground - all the conductive objects around a user are at that same potential. Current is still going to flow in those objects, but there are no points of potential high enough and within a user's reach to be a problem for the user.