Ground Wire in Service Feeder Conduit to Residential Home

[John Billig]

I posted a question previously on bonding and grounding and the responses I received has brought up another question I have. My current home will have a 200 amp panel with a 200amp main breaker. The grounding electrode will be connected from the footing rebar to the ground bus in the panel. The neutral bus and ground bus in the panel will not be joined at the house panel. I have a meter/breaker enclosure back at the transformer which is 300 feet away. I was instructed to run 4 wires from the 200amp meter/breaker enclosure to my house panel and join the ground wire and neutral together at the meter/breaker enclosure. My question is why do I need the ground wire in the feeder conduit? Wouldn't it make more sense to drive a ground rod at the meter/breaker enclosure and attach to the neutral/ground lug? Would save on running a ground wire the 300+ feet.

 

[infinity]

The conductors between the meter/breaker and the house panel are feeder conductors and the feeder requires an equipment grounding conductor run with the feeder. Look at 215.6 which takes you to 250.32(B). You will also as you've stated need a GES at the house which is in your case is a CEE.

215.6 Feeder Equipment Grounding Conductor. Where
a feeder supplies branch circuits in which equipment
grounding conductors are required, the feeder shall include
or provide an equipment grounding conductor in accor-
dance with the provisions of 250.134, to which the equip-
ment grounding conductors of the branch circuits shall be
connected. Where the feeder supplies a separate building or
structure, the requirements of 250.32(B) shall apply.

 

[LarryFine]

You should have a ground rod or two at the meter/main as well. The pedestal and the house are separate structures, and each needs a grounding-electrode system, and an EGC needs to interconnect them.

This is just like running a feeder from a main-breaker panel in a house to a detached garage.

 

[John Billig]

Yes, I agree. Should also have a ground electrode connected to the neutral/ground lug in the Meter/breaker enclosure. Inspector isn't requiring this, but can't hurt to add two ground rods and tie together and connect to ground/neutral lug with #4 copper or #6 aluminum.

 

[LarryFine]

Yes, I agree. Should also have a ground electrode connected to the neutral/ground lug in the Meter/breaker enclosure. Inspector isn't requiring this, but can't hurt to add two ground rods and tie together and connect to ground/neutral lug with #4 copper or #6 aluminum.

Code requires grounding electrodes at the main disconnect.

The main in the house panel doesn't alter any of this, by the way.

And, rods alone never require larger than #6 cu, but #4 al can't be used below 18" above grade. (you got them backwards)

 

[kwired]

Yes, I agree. Should also have a ground electrode connected to the neutral/ground lug in the Meter/breaker enclosure. Inspector isn't requiring this, but can't hurt to add two ground rods and tie together and connect to ground/neutral lug with #4 copper or #6 aluminum.

He should be, unless it is on a pole that already has an electrode connected ahead of the meter - then a grounding electrode system is already in place at that structure (the pole).

 

[eds]

Is there a code section that would disallow upsizing the egc to a #4 and using it both as my gec and egc. Using a irreversible crimp in the house panel to continue the #4 to the Ufer. I thought there was, just can’t locate it

 

[jaggedben]

Is there a code section that would disallow upsizing the egc to a #4 and using it both as my gec and egc. Using a irreversible crimp in the house panel to continue the #4 to the Ufer. I thought there was, just can’t locate it

Look at 250.121. Look at it in your applicable code cycle, because it has changed.