Plumbing current
- Thread starter ap99
- Start date
- Status
- Location
- Massachusetts
It's normal assuming your house is supplied with a metal water main. Do nothing about it.
The NEC requires all electrodes that are available to be use and if the only qualifying electrode is a metal water pipe it must be backed up with a ground rod.
The NEC requires all electrodes that are available to be use and if the only qualifying electrode is a metal water pipe it must be backed up with a ground rod.
- Location
- Massachusetts
In my opinion an electrician operating under the NEC can not remove/disable a qualifying grounding electrode.
You could have a plumber change the water main to plastic.
After that you might have an EC check out the existing rods.
All that said......WHY?
Do you spend a lot of time hanging out at the water main?
You could have a plumber change the water main to plastic.
After that you might have an EC check out the existing rods.
All that said......WHY?
Do you spend a lot of time hanging out at the water main?
I bumped into this site:
http://www.emfservices.com/ground.htm
they say they use a dielectric coupler to solve the problem. Or would i need to change all piping to insulated piping?
http://www.emfservices.com/ground.htm
they say they use a dielectric coupler to solve the problem. Or would i need to change all piping to insulated piping?
ptonsparky
Tom
- Occupation
- EC - retired
If you live in town, with neighbors sharing both POCO transformers and community metallic water lines, there is not much you are going to be able to do other than to make sure you do not have improper neutral bonds in your house.
30mg at the babycrib may be a problem but the fields should drop off very quickly as you get further away from the water line.
Put your master bedroom near the water line and the babies on the far side of the house, or replace all metallic piping systems with plastic.
30mg at the babycrib may be a problem but the fields should drop off very quickly as you get further away from the water line.
Put your master bedroom near the water line and the babies on the far side of the house, or replace all metallic piping systems with plastic.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
ap99 said:
I believe the problem is not with the plumbing but rather with the wiring somewhere on the premise or with the utility power. I would bet somewhere after the load there is a neutral and ground connected together or a circuit that is usuing the ground as a neutral.
I would gauss the area and have someone turn off circuits one at a time to isolate the circuit that may be causing the problem.
winnie
Senior Member
- Location
- Springfield, MA, USA
- Occupation
- Electric motor research
A dielectric coupling would fix the current on the water main.
However this 'fix' would introduce the safety hazard of having non-bonded grounding electrodes. This fix would violate the NEC if the dielectric coupling were inside your house.
I agree with iwire: replacing a few feet of water main outside of your house would both fix this 'problem', without introducing a violation.
That said, is it worth it?
There is very weak evidence of risk, and the magnitude of the risk is quite small. IMHO it is very likely that there is some real risk, but also very likely that the true problem is something _associated_ with small EMFs, and not the EMFs themselves. This could mean that fixing the EMFs would leave the 'true' problem, simply more masked.
Because of the current state of the data, I would not intentionally install a system that created EMFs, and would be willing to incur small costs to remove EMFs, but would not go to any large expense to fix an EMF issue and would not worry about any EMFs that were expensive to fix. Note that there are some code violations will cause EMFs, and should be fixed, not for the EMF issue, but for other significant safety hazards that they present.
-Jon
However this 'fix' would introduce the safety hazard of having non-bonded grounding electrodes. This fix would violate the NEC if the dielectric coupling were inside your house.
I agree with iwire: replacing a few feet of water main outside of your house would both fix this 'problem', without introducing a violation.
That said, is it worth it?
There is very weak evidence of risk, and the magnitude of the risk is quite small. IMHO it is very likely that there is some real risk, but also very likely that the true problem is something _associated_ with small EMFs, and not the EMFs themselves. This could mean that fixing the EMFs would leave the 'true' problem, simply more masked.
Because of the current state of the data, I would not intentionally install a system that created EMFs, and would be willing to incur small costs to remove EMFs, but would not go to any large expense to fix an EMF issue and would not worry about any EMFs that were expensive to fix. Note that there are some code violations will cause EMFs, and should be fixed, not for the EMF issue, but for other significant safety hazards that they present.
-Jon
Ok, when i turn off the main breaker in the house these fields still exist i dont think i share communal water pipes with neighbors. I have tried speaking to a plumbers on this topic but they referred me to an electrician who said the problem is the grounding. I understand there is nothing to worry bout but its convincing others. So would my best bet be replacing a couple of feet of piping with insulated piping? And where would this be replaced exactly?many thanks for your help.
GilbeSpark
Senior Member
- Location
- NC
The main water line for your house runs from the water meter in your front yard to the inside of your house. Your main line is made of metal. Just replace this with plastic pipe.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I cannot understand how there can be emf's when there is no power on at the house? I would be curious to know if the field exists when the power company line is deenergized. 30 MG is a very large reading. Where is the electrical field coming from without a load?
I would call the power company in-- not sure why but they may have some answers. Is the power underground to the house or overhead? If it is underground, I wonder if there is leakage from the power line to the water line. This would be an incentive for the power company to change their lines.
I would call the power company in-- not sure why but they may have some answers. Is the power underground to the house or overhead? If it is underground, I wonder if there is leakage from the power line to the water line. This would be an incentive for the power company to change their lines.
- Location
- Illinois
- Occupation
- retired electrician
Dennis,
Don
Even with the service disconnect off, the water pipe is still in parallel with the grounded conductor assuming a common metal water piping system. The current can be from other services in the area that are also bonded to the water pipe.
Don
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
don_resqcapt19 said:
I guess I am having a hard time understanding that there could be that much current to cause a 30 mg reading.
peter d
Senior Member
- Location
- New England
Dennis Alwon said:
I don't know exact numbers, but I know that even a small amount of imbalanced current can cause big magnetic fields.
karl riley
Senior Member
Dennis, if your 30 mG were measured right on the pipe or grounding electrode conductor, that equals somewhere around 0.3 amps. If you have an ammeter, clamp it around the pipe or conductor to read how many amps.
30 mG at a pipe means nothing unless you or your children sit on the pipe. If you are concerned about health issues, always measure where humans spend time.
0.3 amps is not much. I have measured 20 or more amps on water pipes due to the fact that they present a parallel connection from your service entrance neutral to the transformer. The current goes through the pipe to a neighbor's service and back to the Tformer through their service neutral.
So when your power is off, some of your neighbor's neutral is coming through your pipes and your service neutral.
A dielectric union 10' or more outside the house in the pipe will block the current. Or a short length of plastic pipe. No Code violation.
Karl
30 mG at a pipe means nothing unless you or your children sit on the pipe. If you are concerned about health issues, always measure where humans spend time.
0.3 amps is not much. I have measured 20 or more amps on water pipes due to the fact that they present a parallel connection from your service entrance neutral to the transformer. The current goes through the pipe to a neighbor's service and back to the Tformer through their service neutral.
So when your power is off, some of your neighbor's neutral is coming through your pipes and your service neutral.
A dielectric union 10' or more outside the house in the pipe will block the current. Or a short length of plastic pipe. No Code violation.
Karl
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Karl I was hoping you would chime in. This, of course, is not my situation but the OP's. I have seen readings of 30 mg from a microwave when it was on so I was thinking there would need to be a larger current to have 30 MG. I appreciate the info.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Karl is there a formula (I am sure there is) to calculate mg amps and distance. The further away the lower the mg. How is this calculated in cm?
karl riley
Senior Member
Dennis, whenever you give a mG measurement you must state the distance from the source, unless it is a general condition from a distant source.
Rule of thumb when you put your gaussmeter sensor right on a conductor, the mG reading is about 100 times the unbalanced amps in the conductor. On a pipe it might be 80 times the amps.
mG weakens directly with distance from a linear source. 2' -20 mG; 4' -10 mG.
From a coil source such as a microwave (Tformer source) it weakens with the cube of the distance. From a set of power lines with no net current it weakens with the square of the distance.
You can derive these yourself if you have an accurate gaussmeter.
Karl
Rule of thumb when you put your gaussmeter sensor right on a conductor, the mG reading is about 100 times the unbalanced amps in the conductor. On a pipe it might be 80 times the amps.
mG weakens directly with distance from a linear source. 2' -20 mG; 4' -10 mG.
From a coil source such as a microwave (Tformer source) it weakens with the cube of the distance. From a set of power lines with no net current it weakens with the square of the distance.
You can derive these yourself if you have an accurate gaussmeter.
Karl
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