Calling MRB: Weird Current on Ground

[sberry]

I might be mistaken but I believe the uffer requirement came with 2008?

 

[mrb]

Poco is coming out to verify neutral with the beast.

Recommendation is to install a dielectric union to the water meter. They have had this issue and make this recommendation. They do not want the current on the water lines, it is a safety issue.

I have to install the union.

They do not want the alternative "backup" path.

is there cable TV? isolating the water pipe doesnt fix the problem, all it does is mask it (and possibly damage your electronics in the process)

 

[mrb]

I might be mistaken but I believe the uffer requirement came with 2008?

oldest book i have is 2002 and its permitted there 250.52 A 3 but it became required later. I saw it in tract homes built in 2003 -easier and cheaper than rods.

to clarify the whole water pipe thing:
if metal water pipes are present you have to bond them.

If you are using metal water pipe as your grounding electrode, you need a supplemental electrode (usually a ground rod)

 

[cowboyjosh]

Another suggestion would be if the utility can't isolate this problem is to get a real electrical contractor involved one with a engineer or forensic engineer on staff. What I mean by "real" is not one of those phony franchise outfits that advertise on TV and Radio, call a local outfit that takes on big projects, they usually have the guys who have the smarts and troubleshooting abilities along with the latest in diagnostic toys that could resolve this issue in short order. Sometimes a utility will not find a problem until they are challenged by a electrical engineering firm or contractor that has some pull or some contacts with the higher ups in the utility

Unfortunately there are stray voltages all over, especially in cities, there are countless cases where people have been killed from stray voltages when they walk over man hole covers, touch light poles, etc. Here are a couple article links that will emphasize the dangers of stray voltage and the one story is how the city had to hire a outsider because their guys and the utility couldn't figure out how the deadly shock happened; which drives home my theory why you might need someone beyond the utility.
http://www.wkyc.com/news/news_article.aspx?storyid=6186http://findarticles.com/p/articles/mi_qn4188/is_20030613/ai_n11389430/
http://www.kdvr.com/news/kdvr-dog-electrocute-lawsuit-txt,0,4480982.story

 

[Thedroid]

Can you get to the transformer? If so use a long piece of wire and check continuity from the transformer to your neutral. Analog meter would work best. If you can isolate the utility neutral from your ground system safely, you should be able to check the integrity of your neutral connection.

 

[mrb]

Can you get to the transformer? If so use a long piece of wire and check continuity from the transformer to your neutral. Analog meter would work best. If you can isolate the utility neutral from your ground system safely, you should be able to check the integrity of your neutral connection.

that is insane.......

 

[Joe92GT]

that is insane.......

I was thinking the same thing. The primary side of that transformer is little higher than 240v. No touching needed, you just have to get close enough to it to get killed.

 

[rwhite692]

I think this is actually pretty noticeable in residential areas, sometimes several service from same transformer, a nick in an underground wire somewhere is as likely as anything. The earth is loaded with stray currents from many things. These stray currents come from many sources. One is the fact that between your grounding electrode at home the system transformer, there are currents through the earth in parallel with your service neutral. These are a fact of life and how much current depends on a lot of things. Also, you, or your neighbors could have a piece of UF going out to a yard light that has a nick in the insulation. Black or white, it don't matter. Some current is leaking out of this nicked insulation and will find it's way back to the electrical system through the earth.

Absolutely, we had this happen on our block many years ago, neighbor two houses down had one leg of his underground service feed wire nicked by some guys that he hired to do some tree removal. The degree to which it is observable outside the immediate area will depend a lot on soil composition, moisture, etc.

 

[MrMark]

is there cable TV? isolating the water pipe doesnt fix the problem, all it does is mask it (and possibly damage your electronics in the process)

No cable. Direct TV. Another reason, not that I needed any, not to have Time Warner.

There was .33 amps on the phone ground for some strange reason. Does the phone incoming carry a ground????

 

[MrMark]

Another suggestion would be if the utility can't isolate this problem is to get a real electrical contractor involved one with a engineer or forensic engineer on staff. What I mean by "real" is not one of those phony franchise outfits that advertise on TV and Radio, call a local outfit that takes on big projects, they usually have the guys who have the smarts and troubleshooting abilities along with the latest in diagnostic toys that could resolve this issue in short order. Sometimes a utility will not find a problem until they are challenged by a electrical engineering firm or contractor that has some pull or some contacts with the higher ups in the utility

Unfortunately there are stray voltages all over, especially in cities, there are countless cases where people have been killed from stray voltages when they walk over man hole covers, touch light poles, etc. Here are a couple article links that will emphasize the dangers of stray voltage and the one story is how the city had to hire a outsider because their guys and the utility couldn't figure out how the deadly shock happened; which drives home my theory why you might need someone beyond the utility.
http://www.wkyc.com/news/news_article.aspx?storyid=6186http://findarticles.com/p/articles/mi_qn4188/is_20030613/ai_n11389430/
http://www.kdvr.com/news/kdvr-dog-electrocute-lawsuit-txt,0,4480982.story

Come on, this is ridiculous. Do you think that some "forensic" clowns know more than the combined knowledge of the Poco power quality EE, the linesman, and ME, another EE??? We have real EE's not electrical contractors.

It all makes sense now after study. This is not some crazy scenario. My prior post late last night explained exactly what is happening and what should be happening with the current divider. The current is splitting back on the service neutral and the ground, which is a very low impedance path back in my scenario. Most houses on the block are putting current in that water pipe. The water pipe is smoking hot. I'm surprised that the City has not put in plastic meters or dielectric unions yet. I imagine they have to jumper the water main before working on it. They may have a dielectric union that will fit the water meter tailpiece.

The poco and their Beast confirmed that the neutral is perfect (and I did not have any voltage fluctuations anyway. We disconnected the ground wire from the water bond to make it safe to open the system. Turns out there are other paths for current to get on that cold water pipe so I will have to shut down before opening the water supply to install the bushing.

This is a common problem/scenario. Putting 30-40 percent of neutral current down the water line is not uncommon. That was the question that I was trying to get answered last night and the poco answered it today.

 

[mrb]

Come on, this is ridiculous. Do you think that some "forensic" clowns know more than the combined knowledge of the Poco power quality EE, the linesman, and ME, another EE??? We have real EE's not electrical contractors.

It all makes sense now after study. This is not some crazy scenario. My prior post late last night explained exactly what is happening and what should be happening with the current divider. The current is splitting back on the service neutral and the ground, which is a very low impedance path back in my scenario. Most houses on the block are putting current in that water pipe. The water pipe is smoking hot. I'm surprised that the City has not put in plastic meters or dielectric unions yet. I imagine they have to jumper the water main before working on it. They may have a dielectric union that will fit the water meter tailpiece.

The poco and their Beast confirmed that the neutral is perfect (and I did not have any voltage fluctuations anyway. We disconnected the ground wire from the water bond to make it safe to open the system. Turns out there are other paths for current to get on that cold water pipe so I will have to shut down before opening the water supply to install the bushing.

This is a common problem/scenario. Putting 30-40 percent of neutral current down the water line is not uncommon. That was the question that I was trying to get answered last night and the poco answered it today.

i dont buy it. put in that dielectric union, and you have a potential difference on either side of it -seems dangerous to me.

 

[MrMark]

What is the difference between that and a plastic meter or a plastic water line?

This is the only solution if you want to keep the power out of that pipe. The path on the ground wires simply another low impedance path for the neutral current.

Think about the current paths here. On the one hand you have 1/0 aluminum about 50 feet to the junction block in the handhole. On the other path you have #4 copper (about 30 feet), about 6 feet of 1 inch type L copper, a few feet of steel or cast iron 8 inch main - there are houses right behind me in the alley - another service lateral or laterals of your neighbor(s), then their #4 ground wire, which may be very short to their panel(s), and then the alum neutral(s), which may be quite short compared to yours.

 

[mrb]

What is the difference between that and a plastic meter or a plastic water line?

This is the only solution if you want to keep the power out of that pipe. The path on the ground wires simply another low impedance path for the neutral current.

Think about the current paths here. On the one hand you have 1/0 aluminum about 50 feet to the junction block in the handhole. On the other path you have #4 copper (about 30 feet), about 6 feet of 1 inch type L copper, a few feet of steel or cast iron 8 inch main - there are houses right behind me in the alley - another service lateral or laterals of your neighbor(s), then their #4 ground wire, which may be very short to their panel(s), and then the alum neutral(s), which may be quite short compared to yours.

with plastic pipe you have the seperation distance. with a dielectric union you have the potential difference where someone could touch both sides of it.

 

[MrMark]

Well, the union is going to be underground and not accessible. There is no way a human is going to be able to use his or her body to jumper this. Most of it will be under concrete and only the part of the ****** that connects to the meter will be touchable - with some digging inside the water meter box.

I thought of this last night but I just let the poco engineer do the talking and he made this recommendation. I didn't tell him I wanted to do this. But, I didn't fight him either, because it all seemed to make sense.

The SCE engineer said that many local cities have this problem and some require the unions or have switched to plastic meters. This is a safety issue for the City water departments and it is a safety issue for plumbers within the house.

 

[MrMark]

If I could just replace the whole copper entrance run with plastic (what is used these days in the rest of the world, pex or Cpvc?) I would but, to my knowledge, CA requires copper for domestic water supply.

 

[MrMark]

Copy of 2004 house inspection section attached:

Nothing in the garage, the meter can is on the outside wall directly behind the panel. There is pipe that runs into the ground from the meter can, so the poco may be using that. I'll do a closer look-see next time we're over there. I did describe what I was seeing to the engineer and they will come right out to look it over good when we take possession of the house. He was concerned and wanted to see the inside panel.

Chris,

Look on the other side of that panel. On mine, for example, there is a customer bus bar that faces the outside (through wall panel) "reverse all in one." The ground wire that goes to the UFER or ground rods and the water bond comes up and lands on the bus bar on the outside facing part of the panel. You wouldn't see my wire either if you took a picture of mine like the one you posted.

That bus bar I referred to would be connected to that neutral wire that lands on the combined neutral/ground buss that you are looking at there.

I think the reverse all in one panels are the only way to fly.

 

[mrb]

Copy of 2004 house inspection section attached:

Nothing in the garage, the meter can is on the outside wall directly behind the panel. There is pipe that runs into the ground from the meter can, so the poco may be using that. I'll do a closer look-see next time we're over there. I did describe what I was seeing to the engineer and they will come right out to look it over good when we take possession of the house. He was concerned and wanted to see the inside panel.

i would get a new inspector. he is talking about missing arc faults and 'current code' -current code doesnt matter, what matters is the code in effect at the time the place was built. The problem I see which he didnt address is the neutrals and grounds landed together under one screw. Cant do that -one neutral per screw. I dont know what to make of the grounding without seeing the rest of the service.

 

[mrb]

Well, the union is going to be underground and not accessible. There is no way a human is going to be able to use his or her body to jumper this. Most of it will be under concrete and only the part of the ****** that connects to the meter will be touchable - with some digging inside the water meter box.

I thought of this last night but I just let the poco engineer do the talking and he made this recommendation. I didn't tell him I wanted to do this. But, I didn't fight him either, because it all seemed to make sense.

The SCE engineer said that many local cities have this problem and some require the unions or have switched to plastic meters. This is a safety issue for the City water departments and it is a safety issue for plumbers within the house.

I get your point and i would go with whatever the poco says to do, but it doesnt seem good to me -i need to educate myself more on the matter and what is accepted practice in this situation

 

[MrMark]

Oh, I forgot to mention that in all my testing I discovered that my water heater is putting a half amp or so out on the cold water line.

 

[MrMark]

I get your point and i would go with whatever the poco says to do, but it doesnt seem good to me -i need to educate myself more on the matter and what is accepted practice in this situation

Can you check on this with your industry contacts?

I have learned a ton in the past day with my meters.

 

[Thedroid]

A

that is insane.......

I didn't think so as long as the transformers accesible and close. The outside of the case should be bonded to their neutral and be at ground potential, and if you can safely isolate their neutral from your system you could check the resistance back to the transformer through both the neutral and the waterlines seperately. OP seemed to have the no how as to whether he could do this safely or not.
I also agree with the OP and the Poco that if the impendance of the Neutral and the water mains are similar then you'll have neutral current through both.

My suggestion was based on a small padmount transformer. Do they even guard those things? Its the first of the month, and I've got to go INSIDE the switchhouse of a 43/4.16 40MVA transformer to read the meters. Should I be nervous?

I perform a very similar test on the entire grounding system of a large plant annually.

 

[Falcon67]

Chris,

Look on the other side of that panel. On mine, for example, there is a customer bus bar that faces the outside (through wall panel) "reverse all in one." The ground wire that goes to the UFER or ground rods and the water bond comes up and lands on the bus bar on the outside facing part of the panel. You wouldn't see my wire either if you took a picture of mine like the one you posted.

That bus bar I referred to would be connected to that neutral wire that lands on the combined neutral/ground buss that you are looking at there.

I think the reverse all in one panels are the only way to fly.

Thanks for that detail - will give it a closer look next time we're over there. The poco engineer and I both think there is something else and we're just not seeing it. If BoA would just get on with it, I could tear into the question.

I noticed the neutral/ground screw sharing and thought that "shouldn't be like that". We're not buying that house anyway for other reasons - mostly because there isn't enough open ground around it for a decent shop.

 

[mrb]

A

I didn't think so as long as the transformers accesible and close. The outside of the case should be bonded to their neutral and be at ground potential, and if you can safely isolate their neutral from your system you could check the resistance back to the transformer through both the neutral and the waterlines seperately. OP seemed to have the no how as to whether he could do this safely or not.
I also agree with the OP and the Poco that if the impendance of the Neutral and the water mains are similar then you'll have neutral current through both.

My suggestion was based on a small padmount transformer. Do they even guard those things? Its the first of the month, and I've got to go INSIDE the switchhouse of a 43/4.16 40MVA transformer to read the meters. Should I be nervous?

I perform a very similar test on the entire grounding system of a large plant annually.

the concept of (and even worse suggesting one should do so) a homeowner tampering with a utility transformer is insane (and could result in jail, civil liability, or death)

 

[Joe92GT]

A

I didn't think so as long as the transformers accesible and close. The outside of the case should be bonded to their neutral and be at ground potential, and if you can safely isolate their neutral from your system you could check the resistance back to the transformer through both the neutral and the waterlines seperately. OP seemed to have the no how as to whether he could do this safely or not.
I also agree with the OP and the Poco that if the impendance of the Neutral and the water mains are similar then you'll have neutral current through both.

My suggestion was based on a small padmount transformer. Do they even guard those things? Its the first of the month, and I've got to go INSIDE the switchhouse of a 43/4.16 40MVA transformer to read the meters. Should I be nervous?

I perform a very similar test on the entire grounding system of a large plant annually.

If you are properly trained you should not be worried. Don't think that I am just reacting because of ignorance of electricity. We are in the industry, and I constantly work on high voltage ac and dc applications. With proper training and knowhow it is still something that would never be allowed. You should see what we have to go through in the form of safety checks and meetings, and procedures to work on systems live. Its not uncommon to spend 3-4 hours taking a system down and performing various safety checks, to do a 5 minute repair.

 

[jsigrist]

If you have multiple neutral/ground busses in your service, you might double check that they are all bonded. If you have an isolated neutral bar and a separate ground bar with neutrals landed on both, you could see this scenario. I would be interested if you only had a single circuit live if you see current on both the neutral and ground? Pretty basic I know, but sometimes we miss the simple things.

I know you said there was a recent system upgrade but it is not clear if that included your service. Also it is not clear if this issue existed prior to the upgrade. Measuring the current on one’s ground and neutral is not something most people do on any regular basis.

Thanks,
Jeff

 

[MrMark]

My service entrance is completely new and the factory connections were actually double-checked at installation to make sure everything was correct.

There are separate neutral and ground busses at the entrance but they are bonded together.

If it were just my house, I would be perplexed. But, like I said, it is many houses that have this issue in my block, they just have no clue. This is a very complicated subject matter and, like you said, not something that people check.

I have no idea if this was going on before the undergrounding project, but I imagine the answer is YES. Basically everyone in my district had to have a new service entrance, and every service entrance was inspected by Edison and the City to confirm that conversion could take place. Now, I can tell you that what happened is that a lot of people that didn't have proper electrical grounding electrodes and bonding, now do. That, may actually be causing more houses to put current down the water main.

The City is going to come out and put in a plastic ******.

 

[MrMark]

By the way, these transformers are in vaults in the street (the power drops come in from behind through the alley) and the vaults are filled to the top with sea water. So, it has to be pumped out with a pump before anyone can go in there. And, you would have to put a gun to my head to get me in there as I would consider it near certain death.

Furthermore, the BEAST, was used to confirm poco neutral integrity. The BEAST, which I believe is a small battery generator, puts out 22 amps on one leg and gets it back on the neutral - it basically delivers 22 amps to the grid if I am correct in my thinking - (the BEAST is connected to the panel lugs at the two phase legs and the neutral) and it has voltmeters onboard to watch for drop issues is a connection is poor

 

[jsigrist]

I am suspect of the plastic ****** fixing the issue. Sure it will make the return through ground a higher resistance, but what path will the current now take? Separating this may very well force the real issue to be visible. I am still curious how much current would be on your neutral and the ground system if you only have one active circuit on one leg.

Thanks,
Jeff

 

[MrMark]

I am suspect of the plastic ****** fixing the issue. Sure it will make the return through ground a higher resistance, but what path will the current now take? Separating this may very well force the real issue to be visible. I am still curious how much current would be on your neutral and the ground system if you only have one active circuit on one leg.

Thanks,
Jeff

I don't understand why you are suspicious? The poco neutral and my neutral all the way back to my subpanel were tested and they are solid. The system is new. Others are doing the same. The electrical engineering makes sense that a current divider exists.

I will do the check you are suggesting later but what is your thinking and background, if you don't mind saying?

 

[walrus]

Does every service that has a bonded water line have this issue? I wonder if the issue existed before the new service was installed.

 

[jsigrist]

I find it hard to accept that an effectively bonded system will have the impedance on the ground and neutral to be so similar. I would not expect the currents on neutral and ground to be so close unless your water line and service conductors are essentially in the same trench.

As for my background, I spent 17 years as an electrician and electrical supervisor in a steel mill, but that was a long time ago and I have certainly forgotten a lot that I once knew.

Thanks,
Jeff

 

[MrMark]

I have a feeling all the houses in the area are doing it.

I am going to check across the street where they are not undergrounded and report back.

 

[MrMark]

The poco's ducts and the water line are within a couple feet down the alley.

 

[Thedroid]

I understand the apprehension, but the test I described did not call for the trafo to be opened or tampered with in any way. It was just a simple continuity check from the outside of the case to your system. Disconnecting your neutral (with your house off of course) might have been as simple as removing your grounding screw, and would have allowed an easy comparison. In my parts, these itty bitty transformers are usually located right by the sidewalk and attaching an alligator clip to the OUTSIDE of the case would be very uneventful.

However the utility already proved the neutral so its a moot point. As with any advice on the net YMMV. If you don't know what to expect your in to deep.

 

[MrMark]

At 6 pm my neighbor's house has 5 amps on the water line and I am putting 1.5 amps.

I need to check the situation at night because I can see the lights on so that I know there is some load.

 

[cowboyjosh]

Yeah I do, a engineer or a forensic engineer investigate this **** all the time; in many cases after a incident occurs and they are hired for their professional opinion if there are lawsuits involved or in cases when all else fails. Usually they are the ones we call when were stumped, it truly is a worst case suggestion, but I wanted to put it out there for you in case you need someone to represent you on your behalf. I have to say that, Im a Master Electrician and licensed contractor and giving out any other advice at this point would not be good in terms of covering my ***; It would be like a Doctor making a diagnosis over the internet to a stranger without giving the patient a physical exam. In order for me to be able to give a definite explanation, I'd have to physically see your setup. I have a couple ideas of what might be going on, most of my ideas have already for the most part been covered by others.

Let me explain why utilities give me a headache. As you know already, a utility only has to provide power to the meter socket, from there its on you, and they know that; they care very little what happens beyond that. That said, they could give a rats *** about your issue when it comes down to it, if they determine its not in their plant, they can easily pass the buck to you and unfortunately should something happen (God forbid), their word whether it be the truth or not, holds more water in court then yours, that is unless you have someone on your side, like a professional with a diploma write a report and provide a resolution.

A POCO engineer and linesman are very educated about their system and providing power to your house, beyond that thats why there are electricians for inside the building. I know linesman who will climb poles in a snowstorm but feel uncomfortable doing something as simple as replacing a outlet in their house. You as a homeowner as little as you like to hear it, have very little pull in terms of getting answers or resolution, your "little people" to them. Don't feel bad, even big building owners get the run around from utilities and often times hire contractors, engineers, and forensic electrical engineering firms to aid them in getting resolution to a electrical abnormality. Most POCO don't care, they don't have to, who else you going to get power off the grid from?

As far as the pipes being hot and the city jumping the mains before doing service work, in most cases yes they do jumper before they do work, as discussed there are stray current from all over using water distribution systems as ground.

Did you tell us how old the homes are in your neighborhood?

Come on, this is ridiculous. Do you think that some "forensic" clowns know more than the combined knowledge of the Poco power quality EE, the linesman, and ME, another EE??? We have real EE's not electrical contractors.

It all makes sense now after study. This is not some crazy scenario. My prior post late last night explained exactly what is happening and what should be happening with the current divider. The current is splitting back on the service neutral and the ground, which is a very low impedance path back in my scenario. Most houses on the block are putting current in that water pipe. The water pipe is smoking hot. I'm surprised that the City has not put in plastic meters or dielectric unions yet. I imagine they have to jumper the water main before working on it. They may have a dielectric union that will fit the water meter tailpiece.

The poco and their Beast confirmed that the neutral is perfect (and I did not have any voltage fluctuations anyway. We disconnected the ground wire from the water bond to make it safe to open the system. Turns out there are other paths for current to get on that cold water pipe so I will have to shut down before opening the water supply to install the bushing.

This is a common problem/scenario. Putting 30-40 percent of neutral current down the water line is not uncommon. That was the question that I was trying to get answered last night and the poco answered it today.

 

[MrMark]

I don't know, Edison sure didn't treat me like a little person, they were on this like white on rice and the Power Quality Engineer was on the phone with me with a day after I initiated the service request. The linesman had enough brains to know that this was over their head and to call in the engineer. Actually, they treated me like royalty if you really want to know. They couldn't have been nicer or more helpful. The line crew was back within 30 minutes of me speaking to the engineer and achieving resolution.

Some of the houses are quite old but some are new and all have just had service upgrades. The water main is ducticle iron 6 inch and it runs down the middle of the alley about 3 feet from the sce service conduits. The conduits are at 36 inches and the water main is probably 24 inches or so.

I verified that the poco engineer was an EE and not some Civil masquerading and he was knowledgeable and everything he said made sense and I vetted what he said and found it to be true.

 

[MrMark]

I really don't understand what ideas you might have as to what is going on. The water main is a low impedance path for some houses compared to the neutral leg and they are splitting their unbalanced load current over it at differing current divider ratios. Everyone is bonded to that pipe and it is metal and it is a BIG FAT path. The water in it probably carries a little current too, but nothing can be done about that.

Please go ahead and give your ideas because I want to make sure everything is covered but I really don't see any mystery here, anymore.

 

[walrus]

Turns out there are other paths for current to get on that cold water pipe so I will have to shut down before opening the water supply to install the bushing.
.

So a plumber could get hurt if he worked on your water supply if he didn't shut your main breaker off? Who pays to have the dielectric union put in?
One other thing I'd post this on Mike Holts forum and see what a differing group of electricians say. I'd make sure that you say you aren't electrician, that you are trying to verify what the POCO is telling you.

 

[cowboyjosh]

I don't like any voltage across the plumbing.

A handful of years ago a fella in Florida literally got thrown out of the shower after Lennar Homes subs improperly installed and wired in the central ac unit. Somehow 240 volts were traveling across this unsuspecting homeowners plumbing, and when he was in the shower, went to adjust the shower head and WHAM. Fella will never be right again and the lawsuit put the heating and ac and electrical contractor who did the original work for Lennar out of business.

I second posting this issue on Mike Holts forum, lots of talent contribute on his site, but don't get too pissed if they suggest hiring someone on your own to find the root cause of your issue. Also on Mike Holt chances are there are people who are familiar with the way the utility does things in your part of the world.

One question with me lingers because Im the curious sort, you mentioned the transformers are underground in a vault filled with water. Is your water table that high that the vaults fill on their own from seepage?