AHJ Grounding Electrode Requirement

[jxofaltrds]

So at the end of the day do we need to use 90.4?

"The authority having jurisdiction for
enforcement of the Code has the responsibility for making
interpretations of the rules, for deciding on the approval of
equipment and materials, and for granting the special permission
contemplated in a number of the rules."

So as a group would requiring a bond less than 2' long be reasonable?

Forget about being right or wrong what would be best way to handle our disagreement?

If you HAD to decide bond or not bond?

 

[kwired]

So at the end of the day do we need to use 90.4?

"The authority having jurisdiction for
enforcement of the Code has the responsibility for making
interpretations of the rules, for deciding on the approval of
equipment and materials, and for granting the special permission
contemplated in a number of the rules."

So as a group would requiring a bond less than 2' long be reasonable?

Forget about being right or wrong what would be best way to handle our disagreement?

If you HAD to decide bond or not bond?

90.4 is a tough one. There is necessity to allow AHJ the ability to make some of the decisions that go with it. There also is the possibility that it gives an inspector a God complex.

That said, who is the AHJ? It is not the inspector. The inspector is only a representative of the AHJ. The AHJ is the governing body that adopts the code.

If the inspector makes 90.4 decisions seemingly on the spot, it should be because his employer has already determined the action that should be taken in certain circumstances, not because he is the inspector and has the authority to decide. When something totally unexpected comes up the inspector should not immediately approve or condemn it, it should be taken to his peers or superiors and be a true AHJ decision and not just one persons opinion.

 

[jwelectric]

So at the end of the day do we need to use 90.4?

NO! this section is not enforceable.

If you HAD to decide bond or not bond?

Mr. Rorro asked the same questions I hear a lot, ?What is the primary objective? Is it insuring that the components of the piping system are at the same voltage level? Or, is the purpose of the bonding jumper to carry fault current to trip a breaker??

Once these questions are answered then we can come up with an answer for, ?If you HAD to decide bond or not bond??

I have done enough residential renovation work to know that just about every metal piping system out there has some sort of non-metallic repair somewhere in the system just as when the plumber fix our ice maker he did it with CPVC piping. Now my water piping system will not carry any fault current and over 70% of it is not conductive to the bonding conductor that was installed when the house was first wired. Let me also say it is not something that I worry about either.

This is not so much a problem when working on commercial or industrial piping systems as in most cases the repairs are done with the same type of piping that is there. This is why Mr. Rorro used the water heater that he used in his article, a water heater in a commercial building.
But
The question still remains the same. How is my water piping system going to get energized with the same amount of current that is used to figure my service calculation?

In my honest opinion I think that everyone should be given a pick, shovel, rope, and a bucket and told, ?go ye therefore forward and seek water? until this debate can be settled.

I had a student that was seeking his NC electrical licenses that had worked up north and went school up there. He was of the opinion or should I say he had been taught that the purpose of bonding metal water pipes had to do with someone losing a neutral. After spending some time down here on the side of one of these hills he learned that there are still a lot of people in this world who think of running water as being the one carrying the bucket trying to get back to the wood burning stove to get warm.

I can?t help but wonder what 3000 amps of current would do to ? and ? copper pipes. 3000 amps for .033 seconds (two cycles) and the copper is coming apart. I have a 300 amp service 10 times 300 equals 3000. Using this water pipe for fault current based on the service conductors is nothing short of joke.

Due to a question from a student I started a thread concerning Teflon tape and RMC. I will agree that if the metal piping system is steel pipes that are threaded then we won?t be faced with the leaking joints after a high fault current but I know from experience that it don?t take a lot of heat to spring a leak on copper. If the plumber uses too much Teflon tape on each of the couplings then there will be enough of a voltage drop across the metal water pipe that using it as a fault path is again nothing short of a joke.

Ever hear of using a welder to thaw frozen pipes? Well I am experienced at it in my barn and yes I have left it on the pipes long enough to spring leaks but at least those swayed backed hay burners had water to drink. This little trick also has taught me just how ridiculous using copper pipes to carry the fault of a service.

 

[jxofaltrds]

I say bond me!

 

[don_resqcapt19]

...Ever hear of using a welder to thaw frozen pipes? Well I am experienced at it in my barn and yes I have left it on the pipes long enough to spring leaks but at least those swayed backed hay burners had water to drink. This little trick also has taught me just how ridiculous using copper pipes to carry the fault of a service.

After two fires in the same winter, our city code was changed to forbid the use of a welder to thaw the frozen underground water service pipes. They would connect to the nearest fire hydrant outside and the street side of the water meter inside. In both cases there was no a direct path from the two connection points and the water pipe grounding electrode conductor at a neighboring house heated up enough to start a fire in the neighboring house.

Were the leaks caused by the copper heating enough at the joints to melt the solder?

 

[iceworm]

After two fires in the same winter, our city code was changed to forbid the use of a welder to thaw the frozen underground water service pipes. They would connect to the nearest fire hydrant outside and the street side of the water meter inside. In both cases there was no a direct path from the two connection points and the water pipe grounding electrode conductor at a neighboring house heated up enough to start a fire in the neighboring house. ...

That's too bad. Welders work great for thawing frozen lines. But one does have to be smarter than the welding machine.

ice

 

[don_resqcapt19]

That's too bad. Welders work great for thawing frozen lines. But one does have to be smarter than the welding machine.
ice

I don't see how you can be smarter than the welding machine when you don't know where the current is going. Like I said, the welder was used to thaw the metal underground water service pipe. There is no way to know the path that the current may take. The assumption was that there was a solid path between the fire hydrant and the water service pipe inside the building, but there wasn't and the current took the path that was available and the neighbors house caught on fire. In on of the two fires there was limited damage as someone was home and the fire was caught in the early stages, in the other no one was home and the fire was not caught until it was visible from the outside.

 

[jxofaltrds]

I don't see how you can be smarter than the welding machine when you don't know where the current is going. Like I said, the welder was used to thaw the metal underground water service pipe. There is no way to know the path that the current may take. The assumption was that there was a solid path between the fire hydrant and the water service pipe inside the building, but there wasn't and the current took the path that was available and the neighbors house caught on fire. In on of the two fires there was limited damage as someone was home and the fire was caught in the early stages, in the other no one was home and the fire was not caught until it was visible from the outside.

Kinda like 'it' takes ALL paths?

 

[jxofaltrds]

LOL. Only $16.95 LOL. :slaphead:

http://www.accentshopping.com/product.asp?P_ID=154824

 

[don_resqcapt19]

Kinda like 'it' takes ALL paths?

That is also an issue when trying to thaw the underground water service pipe. If there are parallel paths, it is difficult to flow enough current on the forzen pipe to thaw it.

 

[iceworm]

I don't see how you can be smarter than the welding machine when you don't know where the current is going. Like I said, the welder was used to thaw the metal underground water service pipe. There is no way to know the path that the current may take. The assumption was that there was a solid path between the fire hydrant and the water service pipe inside the building, but there wasn't and the current took the path that was available and the neighbors house caught on fire. ....

Some of us have been around this kind of stuff enough to know when this method can not be used. Some of us have an electric pipethaw machine specifically designed to do this type of work. Some of us understand measuring the current on various paths and disconnecting piping to get the current to go where one wants it go. Some of us understand that high density urban is not the place to do this. Some of us understand residential density with comon utilities takes special care.

I would not use either a pipethaw maching or a welding machine on soldered, hard drawn copper. Besides the obvious joint failure from over heating, UG ,hard drawn CU, usually swells and breaks when it freezes. Now if it were soft copper with Ford couplings I probably would.

So, imo, a law that just bans welding machines isn't a very good law. If the city elected law makers reallly believe that everyone in the city limits is too dumb to thaw piping, then the law should also include pipethaw machines, weed burners, and torches for thawing. Around here more houses are burned down from using weed burners and torches for thawing than from electric pipethawing.

At first I thought you were being obtuse just because I sometimes don't agree with you. Then I realized that was not so. You and I just have way different view points on the governments ability to take care of us. And that is okay.

ice

 

[jwelectric]

Were the leaks caused by the copper heating enough at the joints to melt the solder?

The first time I used this method it was in a 90 that the leak started. I can't swear that the heat from the welder caused the leak but I can say that the leak started before the water started flowing on the other end of the pipe while the welder was attached.

I always get a trickle of water and turn off the welder and let the flowing water do the rest. I am sold that it was the welder that caused the leak as it happened again a couple of years ago to another joint. Both times the drip started while the welder was being used. Could have been a bad sweat joint to start with or it could be that the pressure on the pipe from the freeze done the damage. I don?t know which but do know it happened while the welder was connected.

Of course it is very hard to sweat copper if there is even a little water inside the pipe but when it is frozen I don't know.

I have also heard but never seen with my own eyes that fault current will open joints in copper pipes. I have heard that the heat causes the water to push things apart but I do not know this for sure so I can?t say.
The one time I tried to see what would happen I quickly abandoned the idea simply because of all the sparks I had flying around. This is not one of those things someone should try in their barn unless they have real good insurance. The 100 amp breaker did not trip before I shut it down but the pipe did not rupture either.

This is one of those experiments that I don?t talk about much as it shows my true intelligence or as some would say the lack of??..:lol:

 

[don_resqcapt19]

Some of us have been around this kind of stuff enough to know when this method can not be used. Some of us have an electric pipethaw machine specifically designed to do this type of work. Some of us understand measuring the current on various paths and disconnecting piping to get the current to go where one wants it go. Some of us understand that high density urban is not the place to do this. Some of us understand residential density with comon utilities takes special care.

I would not use either a pipethaw maching or a welding machine on soldered, hard drawn copper. Besides the obvious joint failure from over heating, UG ,hard drawn CU, usually swells and breaks when it freezes. Now if it were soft copper with Ford couplings I probably would.

So, imo, a law that just bans welding machines isn't a very good law. If the city elected law makers reallly believe that everyone in the city limits is too dumb to thaw piping, then the law should also include pipethaw machines, weed burners, and torches for thawing. Around here more houses are burned down from using weed burners and torches for thawing than from electric pipethawing.

At first I thought you were being obtuse just because I sometimes don't agree with you. Then I realized that was not so. You and I just have way different view points on the governments ability to take care of us. And that is okay.

ice

This is in an older small town, not a big urban area. I don't know how you are going to measure the current on the paths that are in the other buildings...you don't have access to them. Now if you are just thawing the pipes in the house itself, then, sure you can check the paths.

I think our rule only applies to thawing the water service pipe between the street main and the house. In that application, there is no way to know what the current path may be.

As far as banning other methods of pipe thawing, those methods would only burn your own house down, and that is just your problem, not the concern of the city. The issue we had was the fires starting in other houses, not the house with the frozen water service pipe.

 

[iceworm]

... I think our rule only applies to thawing the water service pipe between the street main and the house. In that application, there is no way to know what the current path may be. ....

The few times I have live in the city with water service there was shutoff valve between the city line and my house. Pretty easy to tell where the pipes went for those cases. I take it area you are looking at does not have a dedicated shutoff valve for each house.

As I recall (about 20 years ago) we did get a freeze up. The city said their responsibility ended at our shutoff valve. Our problem on our side of the valve. They fixed it, I don't recall how. If it had been on my side of the valve, I'd felt plenty safe using a pipethawing machine or welding machine.

However, I agree, not for every case, not for the unknowledgable.

ice

 

[hurk27]

I have seen welders used to thaw pipes as far back as I can remember when I was very young ( a time I stayed with my aunt and uncle up here) back then very few water pipes were bonded for an electrode, but this method is still being used and I have done so myself but most (I hope) understand that you must remove any water pipe bonding to prevent the exact thing Don mention from happening, all it takes is a dielectric fitting in the water line or a section replaced with plastic and you will send the welders current through the bond to the neutral over to the next door neighbors house through their neutral and bond to their water pipe, seen this happen a few times, if you ever read the instructions to the equipment that is design to thaw pipes this is exactly what it says to do "remove any bonds from the electric service to the pipe to be thawed", along with turning off the main for the house you are trying to thaw the pipes on.

 

[hurk27]

I should add that we also removed any EGC's to any circuits that might also feed appliances connected to the water line, most times we broke the water line right where it came into the building so any EGC's in contact with the water pipe would not have the welder current on it, this included AC/MC and older BX cable, all these paths will be subject to the welder current if not isolated and the pipe you are trying to thaw is not electrically continuous on a common water main.

Like Don said, very dangerous to do if you do not understand all these paths.

 

[don_resqcapt19]

The few times I have live in the city with water service there was shutoff valve between the city line and my house. Pretty easy to tell where the pipes went for those cases. I take it area you are looking at does not have a dedicated shutoff valve for each house.

Yes there are shut off boxes, but they are a number of feet from the main, and the burial depth of the water pipe between the main and the outside shut off is often less than that of the pipe between the shut off and the house. At that time the home owners responsibility started at the female threads on the main. Now that has been changed to the house side of the shut off valve. The common practice to thaw the pipe was to connect to the nearest fire hydrant and to the pipe inside the house.

As I recall (about 20 years ago) we did get a freeze up. The city said their responsibility ended at our shutoff valve. Our problem on our side of the valve. They fixed it, I don't recall how. If it had been on my side of the valve, I'd felt plenty safe using a pipethawing machine or welding machine.

How would you make the connection at the outside shut off? The ones here do not have a solid electrical connection to the water pipe. They are nothing more than a sleeve that sits over the underground shut off valve to permit you to use a valve key to operate the valve.

However, I agree, not for every case, not for the unknowledgable.

ice

Joe home owner or Joe plumber are, in many cases, "unknowledgeable"

 

[iceworm]

... How would you make the connection at the outside shut off? The ones here do not have a solid electrical connection to the water pipe. ...

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.

One other place I remember had circulating lines from the main to the house shutoff. I suspect the lines from the main were 5 feet deep. That place got down to -50F. That one never froze.

The place I am now gets down to -38F (worst in 6 years) The water line is 4 feet deep, PEX, heat traced (replacable), foam insulated (6"). The pitless connector froze up one year. I figured the pump had crapped out. The driller told me it was the pitless frozen and to run water in the top of the well and it would thaw. Hummm where to get water at -30F and the well is froze up. This gets comical quick. My neighbor has water about 500' away. At -30F garden hose is about like a coil spring. So I get it in the garage, warmed up, straightened out, open the garage door and take off running to get it straight before it gets cold. So, 500 feet of garden hose later, from the neighbor's laundry room, is stretched out and stuck down the top of my well. I turn on full hot and wait for the water to come out the well end. It eventually does, but there is not much flow after 500' of 5/8 garder hose. It is just peeing out and is not very hot - like barely above freezing. So I am standing there waiting for it to freeze up and wondering what I am going to do with a 500' icesickle that has the consistency of a #4 rebar. Fifteen minutes later it is still peeing and I turn on the pump. No Joy. Another 10 minutes. Joy. Water starts to flow. I disconnect and drain the hose best I can. Pull it out of the way for plowing the drive. Next spring my ten, brand new, $35, 50', garden hoses get picked up, cleaned up, coiled up. Everybody got a garden hose for next Christmas. Truth. I could have made a bundle if I could have sold tickets.

... Joe home owner or Joe plumber are, in many cases, "unknowledgeable"

Well, in my case, "Ice (DIY) the Worm"

 

[kwired]

The first time I used this method it was in a 90 that the leak started. I can't swear that the heat from the welder caused the leak but I can say that the leak started before the water started flowing on the other end of the pipe while the welder was attached.

I always get a trickle of water and turn off the welder and let the flowing water do the rest. I am sold that it was the welder that caused the leak as it happened again a couple of years ago to another joint. Both times the drip started while the welder was being used. Could have been a bad sweat joint to start with or it could be that the pressure on the pipe from the freeze done the damage. I don?t know which but do know it happened while the welder was connected.

Of course it is very hard to sweat copper if there is even a little water inside the pipe but when it is frozen I don't know.

I have also heard but never seen with my own eyes that fault current will open joints in copper pipes. I have heard that the heat causes the water to push things apart but I do not know this for sure so I can?t say.
The one time I tried to see what would happen I quickly abandoned the idea simply because of all the sparks I had flying around. This is not one of those things someone should try in their barn unless they have real good insurance. The 100 amp breaker did not trip before I shut it down but the pipe did not rupture either.

This is one of those experiments that I don?t talk about much as it shows my true intelligence or as some would say the lack of??..:lol:

I find it hard to believe you can heat the solder enough for it to let loose. If you are trying to install a fitting with just a drop of water in it, solder will not get hot enough until you have vaporized that drop of water with a frozen line you have pretty much unlimited water keeping it from getting hot enough.

My guess is you have cracked line or expanded fitting if it appears to be leaking at the joint from being frozen and once water starts to thaw it is going to leak out.

 

[jxofaltrds]

I find it hard to believe you can heat the solder enough for it to let loose. If you are trying to install a fitting with just a drop of water in it, solder will not get hot enough until you have vaporized that drop of water with a frozen line you have pretty much unlimited water keeping it from getting hot enough.

My guess is you have cracked line or expanded fitting if it appears to be leaking at the joint from being frozen and once water starts to thaw it is going to leak out.

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.