Grounding Electrode Conductor for up-sized service conductors

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hbiss

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
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EC
200A residential service. UG service conductors have been up-sized to 500 kcmil because of the length. Well water with plastic pipe entering building. What size GEC to the water piping? I say #4. Table 250.66 says 1/0.

-Hal
 
BTW, that is not a grounding electrode conductor but a bond-- 2017 has that info in 25.104 but the tables are almost identical
 
I say the GEC depends on the service size, and doesn't have to be upsized because it's not part of the service conductor system.

Added: I see the responses above don't agree with me, but I didn't look in the NEC to give my opinion, so I could be wrong. :roll:
 
LarryFine said:
I say the GEC depends on the service size, and doesn't have to be upsized because it's not part of the service conductor system.

Added: I see the responses above don't agree with me, but I didn't look in the NEC to give my opinion, so I could be wrong. :roll:
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The op called them service conductors-- I assume he installed them so it counts. IMO
 
As Dennis stated it doesn't matter what size the service is you size the GEC based on the SEC's. Look up your SEC size in T250.66 and you're done, that is unless your sizing the GEC for a ground rod or CEE.
[h=2][/h]
 
Definitions

Service Conductors, Underground. The underground conductors
between the service point and the first point of connection
to the service-entrance conductors in a terminal box, meter, or
other enclosure, inside or outside the building wall.
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This was a question asked of me by another EC. Yes, the 500s are service conductors. I agree that we really aren't talking about a GEC but a bonding conductor and believe T250.122 should apply as it would to any other metallic system. Interesting that they make that exception for multiple occupancy water piping in 250.104(A)(2) though the unit must be fed from a sub panel and the piping not electrically continuous with other units .

If it were a GEC connecting to a metallic water service I can see the need for the 1/0. The fact that the conductors are up-sized has nothing to do with the breaker size after them.

-Hal
 
I've always found it interesting (and perplexing) that an interior metal water piping system that is not a grounding electrode requires a 250.102(c) full size bond whereas other piping systems do not.
 
augie47 said:
I've always found it interesting (and perplexing) that an interior metal water piping system that is not a grounding electrode requires a 250.102(c) full size bond whereas other piping systems do not.
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:thumbsup:

You, me and a lot of other people. Are CMP members influenced by rational thought? Hard to tell most days of the week.
 
But now I'm thinking. His question came up because the service panel is about 100 feet away from where the well tank and equipment is. It would be cheaper and easier to run less than 1/0, but 1/0 it has to be. Since there is no requirement to bond the water line where it enters the building as with a GEC, couldn't he just bond to a water line closer to the panel if there is one?

-Hal
 
hbiss said:
But now I'm thinking. His question came up because the service panel is about 100 feet away from where the well tank and equipment is. It would be cheaper and easier to run less than 1/0, but 1/0 it has to be. Since there is no requirement to bond the water line where it enters the building as with a GEC, couldn't he just bond to a water line closer to the panel if there is one?

-Hal
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You can bond the water line, that isn't connected to an underground water pipe, anywhere you please
 
hbiss said:
200A residential service. UG service conductors have been up-sized to 500 kcmil because of the length. Well water with plastic pipe entering building. What size GEC to the water piping? I say #4. Table 250.66 says 1/0.

-Hal
Click to expand...

If its a non metallic water pipe then it does not qualify as a GE. If the interior piping is metallic, then it has to be bonded per 250.104.
Your ufer ground will require a minimum 4 AWG copper
 
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