[TowerTalk] Antenna/Tower Grounding (Lightning Protection)

[Scott Honaker]

The current (some say "dumbed down") Technician class question pool has a
question on tower grounding.  There's no reference given (I would like to
find it).

T0B11 (C) What is considered to be an adequate ground for a tower?

C. Separate 8 foot long ground rods for each tower leg, bonded to
   the tower and each other


-----Original Message-----
From: towertalk-bounces at contesting.com
[mailto:towertalk-bounces at contesting.com] On Behalf Of Jim Lux
Sent: Thursday, January 04, 2007 7:11 AM
To: ersmar at comcast.net; Richard W. Solomon; towertalk at contesting.com
Subject: Re: [TowerTalk] Antenna/Tower Grounding (Lightning Protection)


At 08:52 PM 1/3/2007, ersmar at comcast.net wrote:
>Dick:
>
>      Below are some nuggets of wisdom I've gathered from reading
> the postings on this reflector over the years.
>
>1.     You cannot protect the tower, antennas and rigs from a direct 
>lightning strike.   You can only attempt to minimize the damage if 
>that happens.
>
>2.    Your tower ought to have at least one ground wire, minimum of 
>#8 gauge wire, to one ground rod within two feet of each tower
>leg.  The latest version of the National Electrical Code mandates 
>two ground rods and two wires at each leg.


Really?  Which code? The 2005 NEC is silent on towers, per se.  Art 
810.15 says masts and metal structures shall be grounded in 
accordance with 810.21.  810.21 just has the stuff about the size of 
the wire, straight line runs, protection of the connections, and what 
can serve as a grounding electrode.

Art 820 (CATV etc) has very similar provisions.


Maybe you're thinking of some lightning protection code? Or a 
recommendation of a manufacturer?