On a job that has 1200A 208Y service CT can at xfmr. I have a copper water pipe ground and steel structure ground. My GEC shall be 2/0cu to structure.

My helper(lead man) is wanting to drive several rods to form a grid and take the GEC to the grid I say take it to the structure.

If we drove rods, would the GEC be a #6 as the 2002 code states (250.66)? Or is that for a single rod electrode?



[This message has been edited by arseegee (edited 11-11-2002).]

Where is the service disco?

a few issues at hand here arseegee, i can realte to wanting to ground the s#@! outta everything, i think it's simply inherent in us......

A~
IMHO,it would seem that providing g-rods to the structure would mimic a lightning rod installation, simply aiding the structure in bleeding off a lightning strike.

in terms of an incomming charge to the service itself, a closer grid is a better grid, lower ohmic value following suit....(250.4...et all..)

B~
the reduction of GEC size for "sole electrodes" , to my understanding, means they are all run back to the MBJ individually, applicable to all except A-C in 250.66
Assumably Kirchhof's laws apply here to latter charge....

as to the MBJ, ( and this is a tad of a highjack) , i've ended up in 366.7
(1000a per square inch of cu, 700a for al)
wondering about the last sentron unit's intergrity , with tape measure in hand....