If I suspect the neighbors house is leaking current through the water line into said house (energizing aluminum siding, bathtub piping etc...) and I remove EGC from the water pipe and neighbors house blows up or sends 240V to everything and causes damage can I be sued for being a nice guy and trying to help my customer out ?
Neighbors House leaking current into another Lawsuit
- Thread starter Cletis
- Start date
- Status
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
"Not my problem" falls down when you are aware of an unsafe condition and deliberately make a change, for whatever purpose, that makes the unsafe condition worse.
It could be a POCO problem or a neighbor's problem in terms of location of the neutral fault. But you are aware of the consequences of your action, or else are negligent if unaware.
It could be a POCO problem or a neighbor's problem in terms of location of the neutral fault. But you are aware of the consequences of your action, or else are negligent if unaware.
david
Senior Member
- Location
- Pennsylvania
what do you mean by remove the equipment ground conductor
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
I think he means disconnect the GEC from the bonding point to the water pipe so that his customer's neutral is not carrying his neighbor's neutral current too.
That's exactly what I meant. When we shut the main breaker to house the current is still there so other than maybe service wires or seu wire touching metal, overhead lines or things of that nature (which I haven't seen) the problem must be underground. I was just thinking of being a really nice guy and lifting the egc for a few seconds to take a quick measurement then put back. But I guess nice guys finish last so I'll have them call MR. Sparky I guess at this point
david
Senior Member
- Location
- Pennsylvania
if he has noticeable current on his customers water system at his customers bath tub i would suspect a poor bond to the utility nuetral in his customers dwelling, or a compromised nuetral in his customers house.
If he has current on his customers alum siding i would bond the siding to his system bonding terminal though not a code requirement
the only time i seen siding energized was at a mobile home site where the equipment ground in the four wire feed was compromised
either way bond the siding
edit ,be careful if your right about the hot service conductor making contact with the siding the metal water hose bib might be making contact with the siding
romex jockey
Senior Member
- Location
- Vermont
- Occupation
- electrician
david
Senior Member
- Location
- Pennsylvania
If your service panel is bonded to a ground rod near your meter location you could clamp a grounding electrode conductor to your meter enclosure and bond to the ground rod to make a temp test to see if your costumers nuetral is compromised from the meter to the service panel
after clamping the temp conductor see if these problems go away
your customers nuetral may be using the alum siding to make connection to the utility nuetral at the service drop touching the siding if the outside hose shut offs are mounted or in contact with the siding
gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
190307-1540 EST
There are tests that can be performed that create no liability.
Already performed is turning off the customer's main breaker. No major source of current from the customer's home.
With the customer's main breaker off how large is the current on the customer's GEC, and simultaneously on the customer's neutral from the power company transformer? Are these two currents in phase or out of phase? In other words is the current coming in on the customer's neutral the same current as is going out on the GEC?
What is the voltage drop from the power company's ground rod at the power company's transformer to the customer's neutral bus in the customer's main panel? With an ungrounded delta supply as I am serviced by at my home the transformer ground rod is unique as a transformer grounding point for me and my next door neighbor, the only ones on the transformer. For a wye primary source there are many transformers with their own ground rods and all secondary neutrals connected together by wire and the ground rods and common to all home neutrals. Both primary and secondary neutrals are tied together. A much more complex neutral system, and there may be a water pipe connection between neutrals of homes.
As an approximation under normal home load conditions I would expect a voltage difference between the transformer ground rod and the home's main panel neutral bus of greater than 1 V to be excessive. If at the transformer the transformer neutral terminal is good to the transformer center tap, and from the terminal to ground rod is also good, then the voltage drop ftom transformer center tap to ground rod can considered to be in the millivolt range for likely neutral currents. Thus, using the ground rod as a voltage reference point is like being at the actual transformer center tap. Ground rod resistance to earth is likely not less than 1 ohm, and usually much higher.
If the neutral conductive path, intended wires, is of a high resistance, then at least some neutral current flows out thru the earth and water pipe paths.
Voltage drop and current measurements should allow you to identify the problem without opening anything except previously said main breaker.
You can also make voltage measurements from the transformer ground rod to the home's siding to try to determine the source.
.
There are tests that can be performed that create no liability.
Already performed is turning off the customer's main breaker. No major source of current from the customer's home.
With the customer's main breaker off how large is the current on the customer's GEC, and simultaneously on the customer's neutral from the power company transformer? Are these two currents in phase or out of phase? In other words is the current coming in on the customer's neutral the same current as is going out on the GEC?
What is the voltage drop from the power company's ground rod at the power company's transformer to the customer's neutral bus in the customer's main panel? With an ungrounded delta supply as I am serviced by at my home the transformer ground rod is unique as a transformer grounding point for me and my next door neighbor, the only ones on the transformer. For a wye primary source there are many transformers with their own ground rods and all secondary neutrals connected together by wire and the ground rods and common to all home neutrals. Both primary and secondary neutrals are tied together. A much more complex neutral system, and there may be a water pipe connection between neutrals of homes.
As an approximation under normal home load conditions I would expect a voltage difference between the transformer ground rod and the home's main panel neutral bus of greater than 1 V to be excessive. If at the transformer the transformer neutral terminal is good to the transformer center tap, and from the terminal to ground rod is also good, then the voltage drop ftom transformer center tap to ground rod can considered to be in the millivolt range for likely neutral currents. Thus, using the ground rod as a voltage reference point is like being at the actual transformer center tap. Ground rod resistance to earth is likely not less than 1 ohm, and usually much higher.
If the neutral conductive path, intended wires, is of a high resistance, then at least some neutral current flows out thru the earth and water pipe paths.
Voltage drop and current measurements should allow you to identify the problem without opening anything except previously said main breaker.
You can also make voltage measurements from the transformer ground rod to the home's siding to try to determine the source.
.
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Why not just walk next door, explain that you need to test something at the house you are working on and you want to make sure there are no negative consequences, so you suggest that they open their main breaker while you do it? No way for them to damage anything that way. In fact if your theory is correct, their opening their main should make the problem go away.
Then you have a new client!
Then you have a new client!
- Location
- Illinois
- Occupation
- retired electrician
While bonding something may appear to make the problem go away, it is only masking it. Bonding is never the solution for an issue like this.
david
Senior Member
- Location
- Pennsylvania
True , but many times an over current device will open once something is bonded
and if it is bonded and its a nuetral current issue you wont get shocked while the issue is being resolved
brantmacga
Señor Member
- Location
- Georgia
- Occupation
- Former Child
If you still have current after disconnecting your customers power, then it’s time to call the utility.
Had a similar situation years ago and let the utility handle it; many of them have power quality engineers, and that is part of their job description.
Sent from my iPhone using Tapatalk
Had a similar situation years ago and let the utility handle it; many of them have power quality engineers, and that is part of their job description.
Sent from my iPhone using Tapatalk
romex jockey
Senior Member
- Location
- Vermont
- Occupation
- electrician
Yet practiced, as in equopotential installs on farms that were wired poorly to begin with.....~RJ~
Tony S
Senior Member
- Location
- Resting under the Major Oak UK
I wish you luck with this one. I had the same problem, to find the fault the power company had to disconnect the entire street so I wasn’t the flavour of the month with the neighbours.
gadfly56
Senior Member
- Location
- New Jersey
- Occupation
- Professional Engineer, Fire & Life Safety
- Location
- Illinois
- Occupation
- retired electrician
That is not correct unless you have installed a complete equipotential plane or you are standing on the grounding electrode. Bonding does not eliminate the votlage.
- Location
- Illinois
- Occupation
- retired electrician
While a lot of the farm issues are poor wiring practices at the farm, some of it is the voltage drop on the multi-grounded neutral if the utility is using wye distribution, but in either case the bonding only masks the problem.
AirJoseph
Member
- Location
- British Columbia
I've run into similar situations where current was flowing through the water pipes and found the issue was with the Poco's system neutral.
My situation was that the service was at the end of a long run from the Poco's transformer and the system neutral had too much resistance due to it's length and current took the water line path back to it's source. We were able to improve the issue but not eliminate it by better balancing the loads between phases.
My situation was that the service was at the end of a long run from the Poco's transformer and the system neutral had too much resistance due to it's length and current took the water line path back to it's source. We were able to improve the issue but not eliminate it by better balancing the loads between phases.
david
Senior Member
- Location
- Pennsylvania
Most likely based on the OP other thread on the measurements he has taken indicates a compromised neutral at his customers dwelling,
He needs to get that corrected
If the neutral is defective for the service entrance conductor meter to service panel as the majority are and the neutral is not compromised in the service cable meter to weather head service drop
Bonding the siding would give the voltage a metallic path back to the service conductor’s neutral making it safer than not bonding it until the neutral issue gets resolved
According to your post that will have no effect on the touch potential at the siding
His grounding electrode conductor to rods is bonded in the meter enclosure not the service panel so the bond would be to the service conductor nuetral not the service entrance cable nuetral
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