ECN Forum Forums General Topics of the Trade General Discussion Area grounding light poles

Does anyone know the preferred means of grounding light poles besides the grouding electrode?

There seems to be a big misconception that ground rods should be used to ground light poles. The fact is that connections to earth alone like that have too much resistance (impedance) to be of any use in a tripping a breaker if the pole was to become energized. The preferable method of grounding is by connection to a grounding conductor that is run with the supply wires.

Bill

thanks bill, how about bonding to the re-bar cage?

Mike Holt has been discussing this issue in this newsletter. You should be able to find the topic on his website.
http://mikeholt.com

This is the second attempt to post this reply. Hope is it not a duplicate

Try going to Mike Holt's website. He has been discussing it.
http://mikeholt.com

My experience has always been in low-isokeraunic areas, {5-10…not 100 like in central Florida} but the flat-coil-of-#6-solid-in-the-bottom-of-the-hole ground electrode is useless for clearing 60Hz faults. It is needed for the “lighting rod” characteristics of a lot full of aluminum light standards.

Bjarney,
Can you cite any document or source that says the coil of #6 at the bottom of the hole makes a better grounding electrode than the concrete base and its re-bar?
Don(resqcapt19)

No, I'm sorry I can't. I was taking for granted that a couple of acorn clamps on the #6 from the coil extension passing the rebar cage being a de facto practice—but shoulda’ figured it as a “regional variation." It would be a waste not to take every advantage of a ready-made attribute that comes with cages and concrete. In my experience, that detail seems to show up in a lot of municipal-specification boilerplate, but then again I've not worked in Detroit, Michigan or Muleshoe, Texas.

The ‘coil’ has probably been adapted from the long-standing utility practice for wood-pole butt grounding. The hippest in-the-know electrical experts call it a microUfer matrix. ;-)

ok guys, so should i rely on my grounding electrode in the conduit or should you also run a bonding jumper from the cage through the form of the base to the hand hole.... simplist explanations greatly appreciated...