Service ground question

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SmithBuilt

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Wouldn't the grounding in this be a violation? I could understand one or the other at the CT or at the MDP.
 
you would not have the ground rod comming out of the meter base,it is considered not accessable. the meter base would have a power company installed wire assembly from ct.(a new one for me was the last job needed a ground wire installed by us between ct and meter base)the ground rod out of the mdp is correct.i would suspect that grounds need to be in conduit between mdp and ct cabnet.if there was two ground rods spec'ed for job then they would be in series and ran into mdp.
 
I do CT services that same way. The POCO wants one in the CT can, and I want one in the MDP. Doesn't matter a hill of beans if you have too many.
 
This could just be a mistake because the draftsman used a template from another job.
I have seen many instances where they cut and paste drawings, title blocks, etc. from one job to the next and forget to make the revisions.

recthree said:
you would not have the ground rod comming out of the meter base,it is considered not accessable.
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I can't remember the last time I saw a ground rod here in South Florida that wasn't connected in the meter socket.
We install quite a few service entrance rated transfer switches fed from the meter socket and have yet to relocate the ground rod from the meter.
The drawing shows a 3/0 ground. This is not intended to be connected to a ground rod is it?
 
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The engineer may know, or think that utility in that area requires a rod off of a CT meter pan.

What about a uffer, the water lines and building steel?

It strikes me odd that a building with an MDP would not have at least some of those electrodes.
 
M. D. said:
Who said anything about ground rods???
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My mistake, I took the "3/0- 3/4" as a 3/0 to a 3/4" rod.

The only time I see the 'Ground' symbal used on a print is a connection to earth (GES), not a connection to an EGC.
 
I don't think there will be any building steel, well probably a concrete encased electrode. Of course incoming waterline.

If I tied the 3/0 from the mdp to the rebar and water line. Wouldn't another grounding electrode at the ct create a parallel path, along with the neutral conductor?
 
Verbage is everything!

Verbage is everything!

SmithBuilt said:
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Wouldn't the grounding in this be a violation? I could understand one or the other at the CT or at the MDP.
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No to your question, but due the incomplete nature of the drawing the MDP should be labeled "SE", and that does not change in respect to your orginal question even if this was a downline power distrubution point.
Second is that there no noted amperage on the MDP "SE".
Third theres no amperage on any of the service panels. I'd be scared to see the panels schedules qualify this particial riser diagram ...:rolleyes:
 
SmithBuilt said:
I don't think there will be any building steel, well probably a concrete encased electrode. Of course incoming waterline.

If I tied the 3/0 from the mdp to the rebar and water line. Wouldn't another grounding electrode at the ct create a parallel path, along with the service neutral conductor?
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Any thoughts on this?
 
iwire said:
My mistake, I took the "3/0- 3/4" as a 3/0 to a 3/4" rod.
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In this drawing, it's saying "3/0 conductor in a 3/4" conduit", right?

SmithBuilt said:
If I tied the 3/0 from the mdp to the rebar and water line. Wouldn't another grounding electrode at the ct create a parallel path, along with the neutral conductor?
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A parallel path through what? The earth only? If that what you're saying, that's perfectly compliant. :)
 
I know here that is a compliant installation..the POCO ground there CT cabinets and we are required to ground the service equipment because we do not have access to the CT cabinet even though we install the cabinet for the POCO..I am with bob on this one I would of taken that as a 3/0 to 3/4" grd rod..it does not state the distance between the MDP and the CT cabinet last one I did must be 120 ft..Not that makes a difference..
 
georgestolz said:
In this drawing, it's saying "3/0 conductor in a 3/4" conduit", right?


A parallel path through what? The earth only? If that what you're saying, that's perfectly compliant. :)
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Yes 3/0 in 3/4" conduit.

Yes earth I found a note clarifying, to be connected to 2 10' driven electrodes.
 
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