I'm replumbing my 40 year old house. As part of that, I cut a 3/4" copper pipe to tap in a 3/4" PEX pipe using a SharkBite "T".

Once I cut the 3/4" copper pipe, I felt a tingle of electricity when I touched the pipe. This was particularly worrying because I'm in the crawl space, laying in a puddle of water from the cut pipe.

Anyway, I turned off the main breaker at the panel and resumed my work. However, I was again "tickled" by electricity. At that point, I stopped working.

I assume the copper pipe is being used as a grounding source for the panel. But why is there electricity showing up when I touch the pipe. I also assume I will need to install a bridge across the new " by electricity. At that point, I stopped working.

I assume the copper pipe is being used as a grounding source for the panel. But why is there electricity showing up when I touch the pipe. I also assume I will need to install a bridge across the new " using 2 clamps and a wire. Will installing this bridge allow me to work safely and provide proper grounding for the house in the future?

Thanks,

Glenn

From what you have related I would say that you have a loose neutral. By my logic I would also say that the only logical place for that loose neutral to be, would be the where the main neutral comes into your house.
I suggest that you find a good, (emphasis on good) electrician.

However, there are certain things you can do to confirm this. I assume that when you say you got a tingle when you touched the pipe after cutting, you mean the pipe on the house side of the cut, not the side going into the ground. Apparently because of the loose neutral (meaning a poor neutral connection) you have a voltage on the piping from the grounding of you electrical system. When you cut the pipe you broke that connection to ground.
Using a volt meter do a voltage check between the two pieces of pipe. When you do a voltage check you are measuring the difference in voltage between two conductors. While your tingle indicates a voltage, the voltmeter will confirm that.

What is confusing to me is that you said that you got a tingle after you turned off the main breakers. With the breakers off you should be disconnected from the source of all electrical power (except for the neutral line). That raises the question of where could the voltage be coming from? Look around for possible sources. Do you for instance, have sump pumps with a battery back up and an automatic battery charger.

Yes, you should bond around that Sharkbite connection you have put in the cold water line to insure electrical continuity.
Your grounding system should be grounded at two places, the cold water pipe and the ground rod. Assuming you find a voltage between the cut pipes, turn off the main breakers. Disconnect the grounding wire connecting the water pipe and the grounding wire connected to the ground rod from the neutral buss. I am assuming that you do not have a separate grounding buss in your panel and your grounding wires are connected to the neutral buss.

Do a voltage check between each grounding wire and the neutral buss. A voltage on either would indicate a voltage on your grounding system. Do this with the main breaker on and off.
With the main breakers on, there is a voltage on the neutral system when any appliance or electrical device is in use. Don't forget things like door bells and electrical clocks. Your neutral system is of course connected to the grounding system at the neutral buss. Electricity follows the path of least resistance. The voltage on the neutral system should be returned to it source (the transformer) unless there is some resistance in the neutral system. A loose or poor connection creates resistance. Hence the logic that the main neutral connection may loose. With a loose main neutral the path of least resistance is through the grounding system.

Also do a voltage check between the neutral buss bar and main neutral cable coming into the house (breakers on). A voltage difference here would also indicate a poor connection at the main lug.

You can see now why you will probably need a good electrician to identify and locate the problem.

Good morning. Please help me understand what and where you stopped the copper and installed the PEX.

If you installed the PEX within10' between the water meter and the waterline entry into the home, you now have no Grounding Electrode. Plastic cannot be used as a ground.

Translated that means you now need to install new grounding electrodes, for example, ground rods.

If the PEX is connected after the grounding connection between the panelboard you existing electrode is fine.

If you remove the copper piping system in favor of the PEX, there is no grounding or bonding issue because the new water line is plastic, not metal.

Regardless of that, if you cut the main power from the panelboard, then you should not see or feel any electrical, particularly if the copper is connected by PEX on each end. Again, plastic is not a conductor of electricity.

So, where is the unwanted electrical charge coming from. That's the issue that needs to be resolved.

Install the grounding rod and call a qualified electrician. If you have neighbors close enough it could be an issue with their service as well. All you can do is protect yourself but an electrician (qualified) will be able to determine where the problem originates. Don't wait. Loose connections or broken neutrals can wreak havoc on electronics and pose a dangerous threat to safety.

I measured the voltage across the break; it was 6 volts. I put clamps on each side of the SharkBite "T" and ran a copper wire between them. The tingle was still evident.

New question: How do I confirm that the entire system is grounded?

If you feel a tingle, it's not. Is there a grounding rod and wire connected to your panel or was the connection to your plumbing the only ground? Whenever a plumbing system uses pex or any other non-conductive material you need a grounding rod (2) connected to the service panel or in new construction the ground is also acquired by attaching to the foundation rebar. Have you called the electrician yet?

just for fun...let's say that you have a rancher style dwelling about 40 or 50 feet long. The electric and water service are both located at one end. If you are in the crawl space on the other end, 50 feet away, in bare feet and you touch a grounded pipe you might feel a "tingle"...the polarity of the soil can and does vary from location to location.
Missouri suggests you retain a good electrician and I strongly agree. Have the electrician verify physically a solid connection the copper water line within the first five feet of it's entrance and verify all connection to the ground rod(s) and panel. Tighten the ground and neutral connections.
After that, if this tingle concerns you, additional ground rods properly spaced and installed can alleviate this condition.