Originally Posted By: cbuell This post was automatically imported from our archived forum.
I inspected a brand new home the other day and found that the 200 amp service was grounded with #6cu instead of #4. The builder says that all he cares about is that it was signed off by the city electrical inspector and has a sticker on the meter to prove it. What would you tell your buyer?
– It is easier to change direction than it is to forget where one has been.
Originally Posted By: kmcmahon This post was automatically imported from our archived forum.
Tell him what you’ve found and that it’s wrong. It’s not your argument with the builder, but it’s your job to point out when something is not right. Leave it at that, and your covered.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
What was the ground electrode?
If it was just a rod or two the #6 is all you need but it does need to be in some kind of conduit and if the conduit is metal it must be bonded at both ends.
***2002NEC
250.66(A) Connections to Rod, Pipe, or Plate Electrodes. Where the grounding electrode conductor is connected to rod, pipe, or plate electrodes as permitted in 250.52(A)(5) or 250.52(A)(6), that portion of the conductor that is the sole connection to the grounding electrode shall not be required to be larger than 6 AWG copper wire or 4 AWG aluminum wire.
***
The strange thing is you still have to "bond" a metal cold water pipe with #4 (200a service) even if it is plastic where it leaves the house and into the ground.
***2002NEC
250.104(A)(1) General. Metal water piping system(s) installed in or attached to a building or structure shall be bonded to the service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or to the one or more grounding electrodes used. The bonding jumper(s) shall be sized in accordance with Table 250.66 except as permitted in
250.104(A)(2)<Multi occupancy>
and (A)(3)<multiple buildings>.
***
250 is a fun section that can get a doughnut fight going in an inspector meeting.
Originally Posted By: cbuell This post was automatically imported from our archived forum.
Mike,
Are you sure about the “solid” #4 copper? I don’t think I ever see anything but stranded. Since my original post I have found some info that says #6 is ok to the ground rods but the pipes and jumpers etc have to be #4. It definitely is a snake pit!
– It is easier to change direction than it is to forget where one has been.
Originally Posted By: Charles Palmieri This post was automatically imported from our archived forum.
The size of the Grounding Electrode Conductor is selected (per Table 250.66) with regard to the size (in AWG or Kcmil) of the service entrance conductors. Typically a 200A residential service is supplied by conductors selected from Table 310.15 (B) (6), usually a 2/0 Cu or 4/0 Al. is installed. 250.66 will require a #4 AWG copper or #2 Al GEC. The following addresses the ground rod
250.66 (A) Connections to Rod, Pipe, or Plate Electrodes. Where the grounding electrode conductor is connected to rod, pipe, or plate electrodes as permitted in 250.52(A)(5) or 250.52(A)(6), that portion of the conductor that is the sole connection to the grounding electrode shall not be required to be larger than 6 AWG copper wire or 4 AWG aluminum wire.
250.104 sets out the requirements for bonding other metal systems of the premises.
(A) (1) requires the metal water pipe to be bonded with a conductor sized from table 250.66 and in this case would require a #4 Cu or #2 AL
good luck trying to find a solid conductor of that size. I'm sure that was a mis-print. in general the NEC does not allow solid conductors larger than #10 in raceways, thus market demand is low for larger solid conductors.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Mike Parks wrote:
Back to the original question-- the electrode grounding conductor must be a #4 AWG solid copper.
Mike P.
Mike do you understand that 6 AWG to a rod would meet code? 
Quote:
good luck trying to find a solid conductor of that size. I'm sure that was a mis-print. in general the NEC does not allow solid conductors larger than #10 in raceways
Not a misprint, I can get up to 2 AWG bare solid no problem, sometimes solid is in the job specifications.
Originally Posted By: Greg Fretwell This post was automatically imported from our archived forum.
You can get #4 solid at H/D and Lowes here in Fla. In fact Lowes didn’t even have #8 solid when I was bonding my pool but they did have 6 and 4. I drove across the road and got the #8.
Am I alone here?