[TowerTalk] Best way to attach radial to radial plate

[K8RI on TT]

On 7/2/2011 11:29 AM, Dan Bookwalter wrote:
> I have a DXEngineering radial plate , they suggest using ring terminals , it
> seems to me that if you solder them , if , you taker a lightning strike the
> solder would all be vaporized ? Should I just wrap the wire around the
> screws/bolts and tighten them down that way
Two issues here. Safety first.  You need a good electrical ground at the 
base of the vertical and that's not the radial system. Nor is a single 
ground rod sufficient.  My own preference would be one rod under the 
vertical and  5 or 6 more out 8 to 16 feet in radial fashion.  All 
ground rods would be connected together using bare #2 copper and back to 
the ground plate Ground rod to #2 copper connections would be 
cadwelded.  As for ground rods and bare #2 (or larger) the more the 
merrier depending on your budget and size of your billfold.

It's unlikely a normal lightning strike would vaporize the solder or 
wires. I'd use crimp connectors instead of just wrapping the wire around 
the screws and tightening them down. That would work fine, but 
eventually the wire will oxidize or corrode resulting in poor 
connections although this is highly location dependent.   If there is 
going to be much movement of the wire where it goes into the crimped 
ring terminal then it should not be soldered. Aircraft use a lot of 
crimp terminals where there is a lot of vibration and soldering is 
prohibited as the wire will break at the wire to solder interface.  This 
should not be a problem at the crimp connectors on a ground system.  
Solder will eventually corrode away, but again that too is highly 
location dependent. Solder will also protect the wire to crimp connector 
interface.  Once done give the connection a coat of liquid electrical 
tape to prevent corrosion. Some one mentioned using noalox or oxidation 
preventative between the crimp connector and ground plate which would 
also be a good idea.

A good ground system raises the odds in your favor. The more elaborate 
the system the better the odds, but nothing will give a 100% sure 
protection against lightning and you soon do read the point of 
diminishing returns for cost.

As for static a choke to ground which will likely vaporize with a 
lighting strike, or a matching coil with one end grounded. A spark gap 
or other lightning protection device (PolyPhaser or ICE)  should be used 
at the base of the vertical antenna.

Read the Lightning protection tutorial on  
http://www.protectiongroup.com/PolyPhaser

73

Roger (K8RI)