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Old 01-27-2009, 11:53 AM   #16
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Code Clarification


Quote:
Originally Posted by GoyimPersuasion View Post
and anyone please jump in, how does the current seek it source (transformer) if Service Neutral was cut?? Through what path??
It will conduct a little through the earth electrode, but almost certainly not enough to operate any protection device except a GFCI.

I'm not sure how Speedy can claim that an open service neutral doesn't present a risk of floating all the grounds in a house up to line voltage.

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Old 01-27-2009, 02:01 PM   #17
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If your neutral was cut...your going to know.

The current would then find ways into the electrode system...most likely, if your coax and phone are grounded properly, it would use those. I would also expect very high voltages on circuits and appliances because the appliances would be in the path of the current. Very soon, all of the magic smoke will exit the appliances. The magic smoke is very important in the operation of these devices.

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Old 01-27-2009, 02:15 PM   #18
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Pic of severed neutral

Voltage to appliances would vary due to resistance of the devices.
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Old 01-27-2009, 03:26 PM   #19
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Originally Posted by Gigs View Post
I'm not sure how Speedy can claim that an open service neutral doesn't present a risk of floating all the grounds in a house up to line voltage.
See the image above.
THIS is why we do not connect electrodes or equipment grounds to water pipes beyond the first 5'. Also why any added electrodes must be bonded to the GES.

If there is voltage on the ground it will not flow into the equipment grounding conductors unless there is a path out that way. A correctly installed system will have NO paths.
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Old 01-27-2009, 03:45 PM   #20
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Here is another pic, this is a multiwire branch circuit in the diagram, but your house service is the same thing.... Check out the voltage on the television in the 2nd pic with an open neutral.

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Old 01-27-2009, 05:56 PM   #21
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Just to add... remember that you have a bond to your water lines if the are metal at the neutral buss. That same water line goes out to the street and goes to your neighbors house where it has a water bond also and uses his service entrance neutral for a return. You might be surprised how much current will show up on your metal water line if you are having a failing neutral or open neutral event.
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Old 01-28-2009, 10:35 AM   #22
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Quote:
Originally Posted by rgsgww View Post
If your neutral was cut...your going to know.

The current would then find ways into the electrode system...most likely, if your coax and phone are grounded properly, it would use those. I would also expect very high voltages on circuits and appliances because the appliances would be in the path of the current.
How would i know if i have a failing neutral without getting shocked from the charge on the appliances and without checking the voltage readings on everything connected to the GES, pipes, conduits, boxes, etc etc.???

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.......That same water line goes out to the street and goes to your neighbors house where it has a water bond also and uses his service entrance neutral for a return.
So would the water pipe to the neighbor's neutral be considered a low-impedance path? If so, wouldn't the appliances remain working and i would NOT know the neutral was severed??

Thanks All.

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Old 01-28-2009, 11:25 AM   #23
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Originally Posted by GoyimPersuasion View Post
How would i know if i have a failing neutral without getting shocked from the charge on the appliances and without checking the voltage readings on everything connected to the GES, pipes, conduits, boxes, etc etc.???
Your lights would be very bright, or extremely dim and would change due to the load. Devices would smoke or just not work.


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Originally Posted by GoyimPersuasion View Post
So would the water pipe to the neighbor's neutral be considered a low-impedance path? If so, wouldn't the appliances remain working and i would NOT know the neutral was severed??

Thanks All.
Not exactly, the iron isn't a good conductor. The connections were made to be watertight, not to conduct electricity. I would still expect the same things to happen.
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Old 01-28-2009, 02:00 PM   #24
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Originally Posted by Speedy Petey View Post
See the image above.
THIS is why we do not connect electrodes or equipment grounds to water pipes beyond the first 5'. Also why any added electrodes must be bonded to the GES.
Right, but if there is a ground fault, then there is another connection. The entire grounding system can easily float to line voltages if there is a fault and the service neutral is broken.



Of course someone would notice this quickly since as was pointed out, many things would be going very wrong in their house. But it is possible.
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Old 01-28-2009, 03:44 PM   #25
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Well of course. If there are multiple conditions or faults ANYTHING can happen. Which is what I meant by a correctly installed system.

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