# 400A (320) residential service grounding



## BMA Sparky (Oct 15, 2012)

I am doing a 400a residential service with 2-200a panels. There is no incoming water main, it’s on a well with poly and no ufer. It’s under 2020 code so I’m setting two 200a emergency disconnects outside which will also serve as the service disconnects. Since there is no other means to ground the service I plan to install 2 ground rods. Would it be acceptable to run one #4 to both rods from one disconnect and then a #4 from that disconnect to the other. (#4 because of possibility of physical damage). Should I have a #4 to two rods at each disconnect?


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## Almost Retired (Sep 14, 2021)

i would think a rod and #4 at each disconnect.
it would be best to check with the inspector


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## yankeejoe1141 (Jul 26, 2013)

I thought you don’t have to run anything larger than #6 to ground rods.


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## BMA Sparky (Oct 15, 2012)

You don’t need anything larger than #6 but if it could sustain physical damage they require #4.


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## A Little Short (Nov 11, 2010)

If you are allowed to land the GEC in the meterbase I would just run a #6 or #4 from it to the ground rods. You don't need anything else to the disconnects.


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## yankeejoe1141 (Jul 26, 2013)

BMA Sparky said:


> You don’t need anything larger than #6 but if it could sustain physical damage they require #4.


True, that's why I just sleeve mine in a scrap piece of 1/2 PVC


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## splatz (May 23, 2015)

BMA Sparky said:


> I am doing a 400a residential service with 2-200a panels. There is no incoming water main, it’s on a well with poly and no ufer. It’s under 2020 code so I’m setting two 200a emergency disconnects outside which will also serve as the service disconnects. Since there is no other means to ground the service I plan to install 2 ground rods. Would it be acceptable to run one #4 to both rods from one disconnect and then a #4 from that disconnect to the other. (#4 because of possibility of physical damage). Should I have a #4 to two rods at each disconnect?


There's no rule requiring a grounding electrode per each service disconnect, right? 

I can't think of any rule that would prevent you from arranging the service disconnects and the ground rods in any order you want on the grounding electrode conductor.


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## BMA Sparky (Oct 15, 2012)

A Little Short said:


> If you are allowed to land the GEC in the meterbase I would just run a #6 or #4 from it to the ground rods. You don't need anything else to the disconnects.


We are not permitted to land anything in the meter here


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## Almost Retired (Sep 14, 2021)

for 400A service my poco requires a single #2 GEC


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## BMA Sparky (Oct 15, 2012)

Almost Retired said:


> for 400A service my poco requires a single #2 GEC


If I had a water main or a ufer I would be running a #2 to both panels, but the only grounding means are the rods.


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## Almost Retired (Sep 14, 2021)

BMA Sparky said:


> If I had a water main or a ufer I would be running a #2 to both panels, but the only grounding means are the rods.


 in this area
without a ufer ,, the slab would have failed inspection before anything was built on it
we dont bond to any piping ... strictly ground rods and ufer


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## backstay (Feb 3, 2011)

I just run a single GEC from one rod through both panels and land on the other rod. Gets them all connected and spaces my rods fairly close to the panels. And I use #4 also, for physical Protection.


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## yankeejoe1141 (Jul 26, 2013)

Almost Retired said:


> in this area
> without a ufer ,, the slab would have failed inspection before anything was built on it
> we dont bond to any piping ... strictly ground rods and ufer


The ufer and rods are the grounding electrodes, you still have to bond any metal piping in the building. Now we’re comparing grounding vs bonding.


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## Almost Retired (Sep 14, 2021)

yankeejoe1141 said:


> The ufer and rods are the grounding electrodes, you still have to bond any metal piping in the building. Now we’re comparing grounding vs bonding.


maybe i should have said 

"in my area" ,,, because we dont bond to piping here ... at all

i am not comparing or suggesting that the op's or your requirements are the same as mine


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## yankeejoe1141 (Jul 26, 2013)

Almost Retired said:


> maybe i should have said
> 
> "in my area" ,,, because we dont bond to piping here ... at all
> 
> i am not comparing or suggesting that the op's or your requirements are the same as mine


That’s new to me, I always thought it was our job to bond the metal piping since it was in the NEC. Inspectors up here expect it from the electricians.


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## Almost Retired (Sep 14, 2021)

it isnt done by anyone period. dont ask me why i dont know


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## yankeejoe1141 (Jul 26, 2013)

Almost Retired said:


> it isnt done by anyone period. dont ask me why i dont know


Ok


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## NoBot (Oct 12, 2019)

#6 to ground rods
#2 to Footer Rebar


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