AHJ Grounding Electrode Requirement

[hurk27]

Next winter start a Ready Heater if you have one. Hold a plumbing (copper) joint in front of the heat. The fitting WILL break lose.

View attachment 7248

then try that with a fitting filled with water as most of the plumbing will be?

 

[don_resqcapt19]

The one that froze had an 8" handhole with a pipe down to the valve. It got down to about 0F there and the water line was only 30 inches deep. One could reach down into the pipe and connect a spring clamp to the water line. I also have a vauge memory of a wire coiled up in the pipe - about a #2. ...

If you have a known direct connection between the two points where you are connection the welding leads, then there is not near as much risk of a problem, but that just is not the case in my town. The riser for the water valve is about 2" in diameter and it does not have a solid connection to the valve. There is just no way to make one of the connections at the outside shut off valve, so they make the outside connection at the nearest fire hydrant and then you have no idea of where the current is going and that is the reason the city does not permit that method of thawing the underground service pipe.

 

[kwired]

Next winter start a Ready Heater if you have one. Hold a plumbing (copper) joint in front of the heat. The fitting WILL break lose.

View attachment 7248

I have tried holding one of these:

in front of fittings I wanted to loosen up. They don't loosen up when filled with water, even when only partially filled.

 

[jwelectric]

I have tried holding one of these:

in front of fittings I wanted to loosen up. They don't loosen up when filled with water, even when only partially filled.

I think you are looking at this in a different way. That torch will not produce 1980 degrees F of heat. This is the melting point of copper. A fault current on a copper water pipe will get hot enough to melt the copper with or without water.

Then we have the issue of the pipe turning the water to steam which increases the internal pressure on the pipe causing it to push apart.

I agree that trying to sweat copper with just a little water is near impossible but again we are talking about something entirely different when addressing current flowing on the pipe.

 

[iceworm]

... The riser for the water valve is about 2" in diameter and it does not have a solid connection to the valve. ...

And all of the houses in town are like that? Or just some? Or just the two that burned down?

Probably doesn't matter. Burn down a couple of houses and the city fathers are sure to have a knee-jerk reaction.

If you have a known direct connection between the two points where you are connection the welding leads, then there is not near as much risk of a problem, but that just is not the case in my town. The riser for the water valve is about 2" in diameter and it does not have a solid connection to the valve. There is just no way to make one of the connections at the outside shut off valve, so they make the outside connection at the nearest fire hydrant and then you have no idea of where the current is going and that is the reason the city does not permit that method of thawing the underground service pipe.

I promise - none of the physics or science is lost on me. And I clearly understand the city applied "one size fits all" logic to the issue. I also see there is no possibility your elected law makers will ever understand that "some you can and some you can't".

I don't know what to say other than, "Sometimes it sucks to live in mainland America." :happysad:

ice

 

[don_resqcapt19]

And all of the houses in town are like that? Or just some? Or just the two that burned down?

Probably doesn't matter. Burn down a couple of houses and the city fathers are sure to have a knee-jerk reaction. ...

That is the typical installation, and the valve itself is at least 4' deep. There is just no way to make an electrical connection to the street end of your water service pipe. That is why they would connect to the closest fire hydrant, but it is also why they had no idea where the current would flow.

Now, in the newer areas, it doesn't matter as even when the water service to the building is metallic the new mains are not. There is no way to use a welder to thaw a frozen service in areas where the mains have been replaced with non-metallic one because you don't have any access to the street end of the water service pipe.

There is also a problem with a current path in the newer bell and spigott cast iron mains as there is a rubber gasket the opens the current path.

I promise - none of the physics or science is lost on me. And I clearly understand the city applied "one size fits all" logic to the issue. I also see there is no possibility your elected law makers will ever understand that "some you can and some you can't".

I don't know what to say other than, "Sometimes it sucks to live in mainland America." :happysad:

ice

Given the fact that access to the street end of your water service pipe is not available in our town, I think the city made the correct call.

 

[kwired]

I think you are looking at this in a different way. That torch will not produce 1980 degrees F of heat. This is the melting point of copper. A fault current on a copper water pipe will get hot enough to melt the copper with or without water.

Then we have the issue of the pipe turning the water to steam which increases the internal pressure on the pipe causing it to push apart.

I agree that trying to sweat copper with just a little water is near impossible but again we are talking about something entirely different when addressing current flowing on the pipe.

Ok you shed some light on things I was not thinking of. I still question how much current needs to flow to heat a solder joint to the needed temperature to let go. Larger the pipe the higher the current will need to be. You not only have water/ice inside the pipe but in underground instances you are surrounded by frozen dirt also, so there is a lot of heat sink also.

When using a welder for welding you get a lot of heat at the work point, but the work point is a small area and you are forcing all the current to flow through that small area.

 

[jwelectric]

Ok you shed some light on things I was not thinking of. I still question how much current needs to flow to heat a solder joint to the needed temperature to let go. Larger the pipe the higher the current will need to be. You not only have water/ice inside the pipe but in underground instances you are surrounded by frozen dirt also, so there is a lot of heat sink also.

When using a welder for welding you get a lot of heat at the work point, but the work point is a small area and you are forcing all the current to flow through that small area.

When sweating copper we use a tool that puts the heat in one small area. We heat the copper above 850 degrees F so the solder will flow into the joint. Water in the pipe will conduct the heat away from the pipe.

When current flows on a copper pipe the heat is distributed over the entire surface of the pipe. Unless the water is flowing it will also heat and will not be able to conduct the heat away. It will also expand causing the pressure in the pipe to rise pushing on the pipe. The copper is already stressed by the pressure of the frozen water and the outer edges of the ice will turn to steam should the welder be set to high.

Now this in not my professional opinion but what was described to me by a plumber that has also broke pipes apart using a welder to thaw frozen copper pipes. I don?t know that what he is saying is fact or not but tend to believe he knows more about the subject than I.

I have no opinion of what caused the leaks the two times I have did this and ended up with a leak. All I know is that while I had my little cracker box connected to the pipe is when the leak started. I do not know what caused the leak as I am not trained in the field but I can attest to the fact that the drip started both times while the welder was attached to the pipes.

I have used the same welder on the same pipes with on harm to any joint or the pipe so it is not an everyday occurrence. I am sorry but I just do not have an explanation.

I do wish that I had some insight of my own to offer but I don?t. If I did have some sort of insight on the subject and could throw in some big words people would think I am smart but alas I am nothing more than a poor ole country boy with a limited education. I can barely give change for a dollar. My wife is mad at me because this morning she asked me if I had some change in my pocket. I told her that I had $1.19 in quarters, dimes, and pennies but I couldn?t give her change for a dollar. I had three quarters, four dimes, and four pennies. I get to sleep on the couch tonight.

I remember one time I was in a strange town and asked for directions. The feller told me to go down the street to the twelfth stop light and turn right. At the eleventh light a cop pulled me over and asks me why I had my foot stuck out the window. He thought I was joking when I told him I was counting so I got my ticket.

I am truly sorry that I can?t offer more information but I have devolved a head ace trying to come up with something. All I can come up with is water is matter, matter is made up of atoms, atoms have electrons, and the movement of electrons is known as electron flow and is measured with amps. Amps are pushed by voltage through resistance which produces watts. So this leaves me asking the question, watt is the matter?

Being serious, I just plain don?t know.

 

[kwired]

When sweating copper we use a tool that puts the heat in one small area. We heat the copper above 850 degrees F so the solder will flow into the joint. Water in the pipe will conduct the heat away from the pipe.

When current flows on a copper pipe the heat is distributed over the entire surface of the pipe. Unless the water is flowing it will also heat and will not be able to conduct the heat away. It will also expand causing the pressure in the pipe to rise pushing on the pipe. The copper is already stressed by the pressure of the frozen water and the outer edges of the ice will turn to steam should the welder be set to high.

Now this in not my professional opinion but what was described to me by a plumber that has also broke pipes apart using a welder to thaw frozen copper pipes. I don?t know that what he is saying is fact or not but tend to believe he knows more about the subject than I.

I have no opinion of what caused the leaks the two times I have did this and ended up with a leak. All I know is that while I had my little cracker box connected to the pipe is when the leak started. I do not know what caused the leak as I am not trained in the field but I can attest to the fact that the drip started both times while the welder was attached to the pipes.

I have used the same welder on the same pipes with on harm to any joint or the pipe so it is not an everyday occurrence. I am sorry but I just do not have an explanation.

I do wish that I had some insight of my own to offer but I don?t. If I did have some sort of insight on the subject and could throw in some big words people would think I am smart but alas I am nothing more than a poor ole country boy with a limited education. I can barely give change for a dollar. My wife is mad at me because this morning she asked me if I had some change in my pocket. I told her that I had $1.19 in quarters, dimes, and pennies but I couldn?t give her change for a dollar. I had three quarters, four dimes, and four pennies. I get to sleep on the couch tonight.

I remember one time I was in a strange town and asked for directions. The feller told me to go down the street to the twelfth stop light and turn right. At the eleventh light a cop pulled me over and asks me why I had my foot stuck out the window. He thought I was joking when I told him I was counting so I got my ticket.

I am truly sorry that I can?t offer more information but I have devolved a head ace trying to come up with something. All I can come up with is water is matter, matter is made up of atoms, atoms have electrons, and the movement of electrons is known as electron flow and is measured with amps. Amps are pushed by voltage through resistance which produces watts. So this leaves me asking the question, watt is the matter?

Being serious, I just plain don?t know.

When soldering you are correct - you are applying heat to a small area. When using pipe to carry current the only heat comes from resistance within the pipe. The pipe is simply a conductor, and will have lower resistance at lower temperatures.

What kind of welder is being used? Most likely one with 225 amp or less rating and maybe 48 volts max. That means 10.8 kVA of output is available. I realize there will be heating within the pipe while carrying this current, I find it hard to believe it will be enough to melt solder at joints, and would have to be higher temp yet to melt the copper. I still think if there is breaks in the line it is because of the expansion when the water froze and not because of excess heat in the thawing current. The water and ice inside is a heat sink, how are you going to boil the water and develop pressure from steam while there is still ice in the line? If there is no more ice your mission was accomplished - turn the welder off. Remember the welder is heating the whole line somewhat evenly and not concentrating all the energy on one joint like a torch may do.

 

[cameljoc]

In all of my 40 plus years of performing electrical work I have never come accross a situation where the water pipe was not grounded to the system. The system (NEC) works. :thumbsup:

 

[jxofaltrds]

In all of my 40 plus years of performing electrical work I have never come accross a situation where the water pipe was not grounded to the system. The system (NEC) works. :thumbsup:

:lol:

 

[jwelectric]

In all of my 40 plus years of performing electrical work I have never come accross a situation where the water pipe was not grounded to the system. The system (NEC) works. :thumbsup:

Are you saying grounded or bonded?