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I need to test continuity of EGC between main and detached structure. It is old heavy galvanzied 1" pipe. I am being told that measuring between ungrounded conductor and pipe will not suffice because the soil will bridge any gaps in the pipe...

Is digging up the pipe the only way to assure I am grounded?
 

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Is there a possibility of pulling in a new equipment grounding conductor? Unless the pipe is totally rotted out then I would be surprised if you didn't get a good reading from conductor to pipe.

Not sure what else you could do other than test from the conductor to the pipe
 

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I need to test continuity of EGC between main and detached structure. It is old heavy galvanzied 1" pipe. I am being told that measuring between ungrounded conductor and pipe will not suffice because the soil will bridge any gaps in the pipe...

Is digging up the pipe the only way to assure I am grounded?
Welcome to ET:thumbsup:

Can you pull the proper sized conductor ?

Also if you dig it up then the pipe may be rotted depending on how long it's been under there.
 

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Discussion Starter · #4 ·
Running anything new between the structures is not possible. I was animately told that measureing between hot and the pipe will not provide an accurate reading. The age of the pipe is estimated at 45 y.o.
 

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I don't think you can depend on the pipe if it has been underground for 45 years. I don't understand why you cannot use the pipe as a measurement. If you get the proper ohms what difference does it make. The earth is not going to give you a great pathway so if the pipe were broken then your ohms reading would be very high.
 

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I don't understand why you cannot use the pipe as a measurement. If you get the proper ohms what difference does it make. The earth is not going to give you a great pathway so if the pipe were broken then your ohms reading would be very high.
Because even the slightest continuity will produce a full voltage reading on a modern digital meter.

You would be better off trying to drive a very heavy load with the conduit.
 

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Running anything new between the structures is not possible. I was animately told that measureing between hot and the pipe will not provide an accurate reading. The age of the pipe is estimated at 45 y.o.
Because it is existing there is a very good chance you could use the neutral as the grounding means.

250.32(B)
Exception: For existing premises wiring systems only, the grounded conductor run with the supply to the building or structure shall be permitted to be connected to the building or structure disconnecting means and to the grounding electrode(s) and shall be used for grounding or bonding of
equipment, structures, or frames required to be grounded or bonded where all the requirements of (1), (2), and (3) are met:

(1) An equipment grounding conductor is not run with the supply to the building or structure.

(2) There are no continuous metallic paths bonded to the grounding system in each building or structure involved.

(3) Ground-fault protection of equipment has not been in-stalled on the supply side of the feeder(s).

Where the grounded conductor is used for grounding in accordance with the provision of this exception, the size of the grounded conductor shall not be smaller than the larger of either of the following:

(1) That required by 220.61

(2) That required by 250.122
 

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Minimum height for new overhead spans is 10'. 12' is better........ They are ugly and I personally hate them, but dried lava is a bigger bitch so.......
 

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Bingo. I have run ser between buildings before. Before means like 20 years before. None for a long time, and when I did , the 4th wire was not required for new installs, but I had it anyway. Ser is common for temp poles at townhouse projects also, it isn't beautiful, but it serves the purpose.
 

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why can't you just run a temporary conductor between the buildings for the purpose ? am i missing something ?
 

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Why can't you run quadplex.
You can, if you can find listed quadplex that is of an insulation type covered by the NEC.

Most twin, tri, quadplex for overhead use is unlisted and only marked XLPE which is an insulation type not recognized by the NEC.

Those cables ar used by the power companies and they do not require listing for that use.

Of course it would be safe but it would still be an NEC issue.
 

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How far apart are the buildings?

A Two point ground tester or a ductor/micro-ohmeter/DLRO
 

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I need to test continuity of EGC between main and detached structure. It is old heavy galvanzied 1" pipe. I am being told that measuring between ungrounded conductor and pipe will not suffice because the soil will bridge any gaps in the pipe...

Is digging up the pipe the only way to assure I am grounded?
If the piping is the EGC, disconnect all wires at both ends.
With a meter check from the main panel to the distant panel of what you believe to be the egc. If it is not 0 ohms you need to run a new egc.
 

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If the piping is the EGC, disconnect all wires at both ends.
With a meter check from the main panel to the distant panel of what you believe to be the egc. If it is not 0 ohms you need to run a new egc.
How about reading the thread before posting?:jester:
 
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