ground rod question

[W1RKW]

Had a nasty T-storm come through yesterday and it got me thinking of grounding again.  When my home was built 2 ground rods were driven into the ground for the electrical service. The first is driven right underneath the service entrance panel and the other is connected to the first by a heavy conductor maybe ten feet away from the first.  They are both right up against the concrete foundation.  My question is 1) how effective of a electrical service ground system do I have and 2) if I took a lightning hit at service should I be concerned about the concrete?  I've been thinking of driving a couple of more but locate them out from the house.  My thinking is ground conductivity should be better would distribute the energy away from the house.

[k4kyv]

It wouln't hurt anything to add some more.  Since the steep wavefront of a lightning strike makes it more like rf, a small radial system, with several radials about 20' long would be even more effective.

[W1QWT]

I have two 8 foot ground rods driven into the ground at the base of my tower.
I have one 8 footer in the ground at the base of my 3 band vertical that I use for FM work on 6, 2, and 70 CM. This is on a mast on the side of the garage. It is connected to one of those alpha delta arresters.
WHere my other cables come into the house I have a them all go through  ALpha Deltas which are all
grounded to a 8 foot ground rod driven 3 feet away from my foundation.
SO far so good. Does this seem reasonable? Lightning is one of those things that in my opinion can not be predicted.

Now for my balanced feedline it goes to a two pole double throw strapping knife switch.
When I am not using the station this knife switch is in a position that has the entry feedline disconnected and the arial feedline is connected to ground.
This ground is a 3 foot diameter circular ring of 3/8 copper tubing but it is only buried about 3 feet down.
Is there a consensus as to how far down a ground must be?

Regards
Q
W1QWT

[flintstone mop]

Thanks
Ya'll are reminding me to get something in the ground at the new QTH. Grounding to the cold water pipe is not enough. I did connect the cold and hot water pipes together. I think that is something NEW/Old from the NEC??? The electrical service definitely needs that ground rod ground, though.
Hopefully I'll put a big note on the radio to get some rods in during fall or next spring. It's an energy level thing for me at this time.
G'day from MOP radio

Fred

[wa6mtz]

You might check the web for Polyphaser out of Carson City, Nevada. They may have some good info on lightning protection. They are one of the leaders in that field. Concrete is a ground for lightning but perhaps not the best. I have seen a microwave tower hit by lightning that was on a concrete base and it cracked the base. Normally lightning will dissipate in an 8 foot diameter from a ground rod so placing two ground rods withing  a shorter distance is a waste of ground rods. Connecting ground rods together with a heavy copper conductor is a good way to go and of course, the more the better. When running a conductor to a ground system, try to keep the conductor as straight as possible as lightning don't like to follow sharp bends and will burn the conductor in two at a sharp bend. Polyphaser
has a lot of new theories on lightning protection especially for antennas, towers and equipment. Of course a hard hit by lightning will do a lot of damage but one can do quite a bit to help on the near proximity lightning damage.