Pole Base grounding

[hurk27]

Re: Pole Base grounding

Charlie Tuna I agree about a lower resistance path for fault current path. I was just commenting on the effect of a lightning strike. and I also agree with what happens to the EGC after a few years of moisture on a connection this is why I said a grid cad welded to the pole would give the greatest protection like it does at a power stations fence line.

 

[charlie tuna]

Re: Pole Base grounding

dereck,
lighning does some crazy things--what it's frequency is--who knows? ground rod resistance varies greatly in different areas of the country. here in florida with a very high water table you would think it good---well we now know it isn't. you can drive a ground rod fifty foot long and not trip a 15 amp breaker. you and i have both seen lightning damage things away from the pole that was hit and these pole have ground rods--why did it blow the lighting contactor off the wall??
my question: are these additional ground rods benificial to the industry?

 

[dereckbc]

Re: Pole Base grounding

Charlie Tuna, all I am saying is a properly designed GES at the pole, offers a much lower impedance to earth at lightning frequencies than the EGC back at the facility. Yes lightning does some odd things and contains many frequencies from DC to RF. The current will split and take all paths availible to it. The GES at the pole will shunt most of it, some will follow the EGC back to the facility, develop high voltage, and reak havoc in some circumstances.

To answer your qustion, I believe a GES bond at the pole will minimze damage or eliminate damage in the facility. I am not saying a ground rod is the answer. I use a Ufer system, which requires minimal expense.