ECN Forum
Posted By: mj water "meter reader" shocked - 11/22/02 02:32 AM
yesterday i was called out by the city to investigate why a "water meter reader" was shocked as he lifted to cover of a water meter to check for leaks. I checked the voltage from the meter assembly to ground, the reading was 120 volts. afer observing the service entrance, i notice that the netural conductor was broken .this was a frist timer for me. has anyone else had this experience?
Posted By: fla sparkey Re: water "meter reader" shocked - 11/22/02 03:06 AM
I was called out to an older house because a plumber who was working on repairing a broken line to the house was shocked.

I arrived after the plumber had left. He had turned off the main to the home to finish his repair.

The main service did not have a ground rod installed and the neutral in the meter can was loose. The service was bonded to the water pipe only.

I repaired the loose neutral and added two ground rods to the service.

When the plumber made the repair I noticed that he had replaced the galvanized pipe that broke with pvc plastic.

Most of the water pipes in newer subdivisions around here are plastic. I always drive two ground rods on a new service.
Posted By: HotLine1 Re: water "meter reader" shocked - 11/22/02 03:34 AM
Hey Fla Sparky:
Welcome to the ECN.....
BTW, doesn't 250-56 NEC ('99 still in effect here) require two rods, or do you document the "less than 25 Ohms" for the AHJ?

PS: TO MJ

Yup, been there, done that many times.....

John
Posted By: mj Re: water "meter reader" shocked - 11/22/02 03:58 AM
hotline1, how would you prove the 25 ohms or less, one of those $2000 meters, or the old way with the in line fuse, etc...any other tests for checking for the 25 ohms or less ?
Posted By: fla sparkey Re: water "meter reader" shocked - 11/22/02 03:59 AM
Hotline we had a couple of municipalities around here that only required a single rod if you also bonded to the cold water pipe.

The inspectors didn't ask for the ohms to ground reading.

[This message has been edited by fla sparkey (edited 11-21-2002).]
Posted By: Surge_in_fl Re: water "meter reader" shocked - 11/22/02 05:15 AM
https://www.electrical-contractor.net/The_Store/EX/382152.htm
This is the meg tester I use.
I do mostly cell tower sites and we must show under 5 ohms resistance and it works great.
Our AHJ requires 2 ground rods, water bond and building steel if available. Also Ufer bond on new construction in place of the 2 ground rods, but no proof of resistance test
Posted By: Scott35 Re: water "meter reader" shocked - 11/22/02 06:01 AM
Don "Resqcapt19" and a few other Members have brought up this item in past threads. Threads also have links to data / documents regarding this situation.

It's not something new. Said Threads have plenty of Rants and Raves from me if you want to read my crazy views on the subject.

Scott s.e.t.
Posted By: sparky Re: water "meter reader" shocked - 11/22/02 10:58 AM
Scott, i would say your 'views' per past threads were quite enlightening
[Linked Image]

on topic

bad noodle & municipal h2o... [Linked Image]

bad noodle, baaaddddd noooooddddlleee....

[This message has been edited by sparky (edited 11-22-2002).]
Posted By: resqcapt19 Re: water "meter reader" shocked - 11/22/02 12:53 PM
mj,
How was the equipment in the building working with an open neutral? In many cases the metal underground water piping system will connect to a number of buildings providing a path for the neutral current, but in those cases there will be very little voltage to ground. As far as grounding rod or other types of electrodes, while required by code, they would do little prevent the shock incident described above.
Don
Posted By: mj Re: water "meter reader" shocked - 11/22/02 06:09 PM
i dont know what caused the voltage to read 120 to ground, .. but when the power company came out and re-connected the netural conductor everything was back to normal.
Posted By: sparky Re: water "meter reader" shocked - 11/22/02 09:58 PM
mj,


was the building in question was operating at some sort of 140/100 (or similar)voltages....
Posted By: Cindy Re: water "meter reader" shocked - 11/23/02 01:38 AM
some threads to bond with:

Water Pipe GE

Gas Pipe Bonding
Posted By: mj Re: water "meter reader" shocked - 11/24/02 01:31 AM
sparky, it was a resident 120/240 single phase, i call the po company eng, and he coulnt not tell me why the broken netural caused voltage to read 120 volt to ground
Posted By: bobc Re: water "meter reader" shocked - 11/25/02 09:21 PM
mj,have seen this problem,is the service overhead and is the pole close to the water
meter.if the soil is moist enough the return path is through the water line to the poco pole bond,all of the "neutrals"on the poco system are bonded together the pole bond is connected to the "neutral system on the pole in our service area
Posted By: resqcapt19 Re: water "meter reader" shocked - 11/25/02 10:58 PM
Bob,
Exactly how would that raise the water meter to 120 volts above earth?
Don
Posted By: Scott35 Re: water "meter reader" shocked - 11/26/02 02:53 AM
Been wondering about the 120 VAC also!!!
Have to get this figured out so I can sleep at night! [Linked Image]
[i.e.: laying awake running different scenarios thru my mind].

Since the Water Meter is still connected, this does not equate to the "Commonly" occuring shock related to an Open Grounded Neutral Conductor at the service.
This would result in a potential of 120 VAC (+/-) measured between the Input and Output sides of the Water Main (where the Meter goes), with the meter removed.

Sounds like possibly could be one or more of the following:

<OL TYPE=A>

[*]Non-Metallic section of pipe on City's Input side of meter, and this Electrical Service has open grounded neutral connection at the service, or re-ground bonded neutral(s) on load side of service,
or


[*]Non-Metallic section of pipe on the output side of all meters - except one - and the one with complete metallic pipe has open Gr. Cond. at service,
or


[*]Finding 120 VAC with open Gr. Cond. at service because water lines are not bonded to GES,
or


[*]Once again, need to call an exorcist!!!
</OL>

<Personal Rantings>
Situations like this are why I dislike using a multi connected C.W. Grounding Electrode, but would prefer isolating the C.W. lines from the City's main with a Non-Metallic pipe section and just bond the metallic water pipes
</Personal Rantings>

As said before by members, a Water Well is one heck of a kick-a** Grounding Electrode.
Combine a Ufer type Electrode with a Water Well, and you have a solid Grounding System which would help out alot with Lightning Discharges, plus isolate the System from problems created by / on a multi connected grounding electrode scheme, and / or brought in from distant areas.
[lightning comes to mind again].

Just some eccentric thinking again!

Scott s.e.t.
Posted By: hurk27 Re: water "meter reader" shocked - 11/26/02 05:18 AM
I had one that had 178 volts to ground but it was the neutral at the primary side of the transformer that went bad. and must of been bad for some time as it took long enough to burn off two ground rods and the concetric neutral that was shielding the hv cable feeding the transformer. the underground water pipes had to be replaced too as they were about gone. if everything would of totaly open to ground then it would of caused a fire or probly got someone killed as the grounding system that was left could of gone as high as the primary hot 7200 volts. this is one reasone that I dont like the poco's bonding the neutral of the primarys to the neutral of the secondarys on transformers
© ECN Electrical Forums