Can water be energized?

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ritelec

ritelec

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Location
Jersey
Caught this and has me thinking. It's suggested there could be a problem with the utility.





"Tonight my wife mentioned that she can feel a slight shock if she puts her hand in the kitchen sink drain. There is a garbage disposal so I assumed that may be involved.
I tried sticking my hand down there and couldn't feel anything, but I got out the multimeter and there is 1.8 volts between the metal sink body and ground. If I hold the probe in the water stream and put the other probe in the ground on a nearby receptical I still get 1.8 volts. There is no voltage between the body of the disposal and ground. It seems that the disposal body is acting as part of a ground path in the circuit that causes my wife to get shocked. I even turned of power to the disposal and get the same results.

No other sinks in the house have this issue, including one that is a few feet away.

The cold water pipe is bonded where it turns to copper, but it enters the house as pex.

I can see the entire length of the pipes between the sink and where the water enters the house. There are no wires touching anything, except the ground. I checked for voltage on the ground at that point and found none.

Basically, I don't think it is an issue with voltage on the ground.

Has anyone got any ideas? My next step is to start isolating the source of the voltage by turning off circuits one by one and see if it goes away. Next after that is call an electrician.



Ok. To follow-up.... I just went through every circuit in the house one by one and I still get voltage. Then I tripped the main breaker and I still get the exact same reading. 1.8 volts between the body of the sink (or the water stream) and ground.

This isn't showing up on any other sink, so I don't think I have a bad multimeter.

This sink is the only one with a single handle faucet, so hot and cold are mixed, but there are no other significant differences between it and the others.

Granted , 1.8 volts is a pretty small amount of voltage. I can't feel it myself, but my wife says she does."




Anyone run into something like this?
 
ritelec said:
The cold water pipe is bonded where it turns to copper, but it enters the house as pex.
Click to expand...

When you measure a voltage that is really a difference in potential between point (A) and point (B).

The idea is to keep everything that is supposed to be grounded at as close to the same potential as possible. That way when you measure from point (A) to point (B) you get (0) volts.

So the cold water is bonded where it turns to copper? Good. But you may want to make sure connections are tight at the clamp and in the panel.

Next there should be a bonding jumper around the pressure reduction valve. The connectors of the newer valves are not conductive. Next there should be a bonding jumper between hot and cold water at the water heater. Again these connections are not conductive and you would have a difference of potential.

Make sure that all water pipes are properly bonded.
 
ritelec said:
Granted , 1.8 volts is a pretty small amount of voltage. I can't feel it myself, but my wife says she does." Anyone run into something like this?
Click to expand...

Yes, yes I have. Have your girlfriend test it. I have found that women get more sensitive after you are married.

This may or may not be a joke.
 
Bond the metal sink.

When you bonded the metal interior water piping system, you energized it with a voltage that is the voltage drop on the grounded conductor on the line side of the main bonding jumper, and/or the voltage drop on the utility primary conductor.
 
ritelec said:
Caught this and has me thinking. It's suggested there could be a problem with the utility.


"Tonight my wife mentioned that she can feel a slight shock if she puts her hand in the kitchen sink drain. There is a garbage disposal so I assumed that may be involved.
I tried sticking my hand down there and couldn't feel anything, but I got out the multimeter and there is 1.8 volts between the metal sink body and ground. If I hold the probe in the water stream and put the other probe in the ground on a nearby receptical I still get 1.8 volts. There is no voltage between the body of the disposal and ground. It seems that the disposal body is acting as part of a ground path in the circuit that causes my wife to get shocked. I even turned of power to the disposal and get the same results.
Click to expand...

Might depend on the measuring instrument.
Digital meters have a high input impedance.
I have a cheapy that's kept in a kitchen drawer.
Unbeknownst to her, I stuck the probes in either end of a pasta salad Mrs B was about to have and measured over a third of a volt.
 
I remember reading a thread that had some of the similar issues, IIRC it turned out to be an
issue with the telephone or cable company's equipment causing the voltage present.
IIRC it was two or three poles down from the house in question.


ritelec said:
Caught this and has me thinking. It's suggested there could be a problem with the utility.





"Tonight my wife mentioned that she can feel a slight shock if she puts her hand in the kitchen sink drain. There is a garbage disposal so I assumed that may be involved.
I tried sticking my hand down there and couldn't feel anything, but I got out the multimeter and there is 1.8 volts between the metal sink body and ground. If I hold the probe in the water stream and put the other probe in the ground on a nearby receptical I still get 1.8 volts. There is no voltage between the body of the disposal and ground. It seems that the disposal body is acting as part of a ground path in the circuit that causes my wife to get shocked. I even turned of power to the disposal and get the same results.

No other sinks in the house have this issue, including one that is a few feet away.

The cold water pipe is bonded where it turns to copper, but it enters the house as pex.

I can see the entire length of the pipes between the sink and where the water enters the house. There are no wires touching anything, except the ground. I checked for voltage on the ground at that point and found none.

Basically, I don't think it is an issue with voltage on the ground.

Has anyone got any ideas? My next step is to start isolating the source of the voltage by turning off circuits one by one and see if it goes away. Next after that is call an electrician.



Ok. To follow-up.... I just went through every circuit in the house one by one and I still get voltage. Then I tripped the main breaker and I still get the exact same reading. 1.8 volts between the body of the sink (or the water stream) and ground.

This isn't showing up on any other sink, so I don't think I have a bad multimeter.

This sink is the only one with a single handle faucet, so hot and cold are mixed, but there are no other significant differences between it and the others.

Granted , 1.8 volts is a pretty small amount of voltage. I can't feel it myself, but my wife says she does."




Anyone run into something like this?
Click to expand...
 
If the water coming to the sink is in PEX or other non-conductive pipe and the metal faucet is not connected to anything else, then the water itself must be the voltage source. Either from the upstream pipe or some isolated metal fitting it is passing through.
But the faucet, sink, and drain should all be bonded together unless they are effectively isolated by rubber or plastic gaskets.
Try bonding them all with wire.

Tapatalk!
 
UPDATE


"Thanks for the many suggestions.

To answer a few questions...

The ground rods are in good shape. A new panel was installed a couple months ago (by an electrician, not DIY) and new copper clad rods were installed at that time.

All of the pipes inside the house are copper. The pipe between the well and the house is plastic. The plastic extends inside for about a foot.

The sink in question is not the closest to the panel. There is a utility sink, as well as a washing machine in between.

I share a transformer with one neighbor. The service comes in from above.

Several people have mentioned a "utility neutral issue" as a possibility. What kind of issue?
When the panel was upgraded the conductors between the meter and weather head were also replaced, so that could be a spot where something isn't connected properly.

Also, this is a very small amount of voltage, like AA battery small. Is this a life safety kind of emergency where the voltage could suddenly increase, or can I take some time to investigate and shop around for a good electrician."



"I just went down to the basement and checked the pipes just before they go into the kitchen above.
There was a nearby junction box so I used the ground there.
I didn't find any voltage on either the hot or cold pipes. I did get 2.2 volts between the copper drain pipe and ground.
The drain starts at the laundry/utility sink then goes to the kitchen sink, then out of the house where it transitions to a mix of cast iron, pvc, and concrete.

Also, I used my Sperry multimeter and a cheap HF one to double check."


"The cold water pipe is bonded. I just double checked. I also remember the electrician who installed my panel a few months ago re-doing it because he didn't like the way it had been done previously.
I'm tempted to pull out a piece of the metal drain assembly under the sink and see what happens. My wife is using the kitchen all day today so that will have to wait.

Another thought, and maybe this is a really dumb thought. Is there a chance this is a static build up from large amounts of water draining from the washing machine through the copper drain pipe? That might explain why I don't see a change when I turn off the power."




"So I just wrapped a piece of 14 gauge wire around the cold water pipe and the drain. The voltage is gone now. I also asked my wife to try and shock herself. That got a nice reaction from her, but she said she can't feel it anymore.

That seems to have been the issue. My guess would be that the disposal interrupts the continuity between the copper cold water/ground system and the copper drain system. I'll bond the two together more permanently in the near future."
 
I don't think there are any issues here, except the fact that when current flows on a conductor there is a voltage drop and the fact that when you connect an energized conductor to earth, you do not reduce the voltage on the energized conductor.

it appears that you are seeing the voltage drop on the grounded conductor to your house.

If the copper drain pipe was not connected to the electrical grounding system, it would be at earth (zero voltage). The electrical grounding system is at an elevated voltage as referenced to "remote earth" (remote earth is earth outside the influence of a grounding electrode, often said to be 50' from a grounding electrode). With the copper drain pipe not bonded and the water piping bonded, you were reading the service grounded conductor voltage drop.

You could install a short rod or even a long screw driver in the earth about 50' away from the service grounding electrodes and measure the voltage between the two points, I would expect you would find the same 1.8 volts.
 
No, there is no chance that friction would build up a voltage on the water. Especially not AC.
However, since the copper water pipe is bonded to the utility neutral and the drain pipe is not bonded (not required by NEC anyway) but goes into the earth the two will be at different voltages if the utility neutral is not actually at earth ground.
That is why others are suggesting a utility issue (not necessarily problem).
If the disposal interrupted the ground to the sink, bridging the pipe downstream from the sink to the water pipe would not help.

As far as the next step in the utility investigation is concerned, leave that to a more competent than average electrician.

Tapatalk!
 
"Ok. Since I no longer have any stray voltage it seems fixed to me. If I didn't have a garbage disposal interrupting the continuity between the drain and the cold water pipe I don't think I would have ever had a detectable issue in the first place.

I have an electrician friend who I'll ask to take a look in the future, but for now I can't find any more stray voltage anywhere.

Could the earth under my house have been acting like a battery and the copper drain and copper ground on opposite sides if the house were allowing my wife to complete the circuit at the sink? Kinda like the old potato clock experiment they make you do in junior high.
I'm in western WA, and I live near a small lake so the ground is pretty wet around here."




What should be the home owners next course of action? Thank you.
 
John120/240 said:
Un plug the disposal & see if it goes away
Click to expand...

charlie b said:
If tripping the main breaker did not make the symptom go away, then unplugging a single load won't do it either. This is a utility problem, and I would report it to them.
Click to expand...
I think we later find out that there was issue with voltage between the drain line and most likely the service grounded conductor, but I was going to mention that unplugging the disposer would interrupt the EGC of that disposer and if the voltage went away when doing so that may help lead us in the right direction of determining the source of the voltage.

People sometimes forget to bond metal waste plumbing piping systems when they are present, would not be the first time I had seen something similar to what the OP has here. Seen same thing more then once before with a bathtub where there was metal plumbing - both water and waste lines. The waste line is not bonded to the electrical system but the water line is, for whatever reason there is voltage drop imposed on the incoming grounded service conductor (may even be from utility primary neutral), which raises the voltage to ground on everything bonded to the grounded service conductor (including the metal water piping) but the waste line is not bonded and is at ground potential. A person using the bath tub is in the water that is in contact with the drain line and when they touch the water faucet is subject to that voltage between the water line and waste line.
 
kwired said:
A person using the bath tub is in the water that is in contact with the drain line and when they touch the water faucet is subject to that voltage between the water line and waste line.
Click to expand...

Or an infant baby getting bathed in a kitchen sink.



Thanks guys
 
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