[TowerTalk] Antenna/Tower Grounding (Lightning Protection)

[Phil Camera]

Even though a search through the archives will reveal the same information, many times over the past number of years (at mulitple times per each year), I'll state my understanding of the good practices and also what I have for my system.

To me there are 5 parts to a well designed grounding system.

1.  Tower ground
2.  Cable ground
3.  SPG
4.  Shack ground
5.  Electric service ground

1.  Polyphaser recommends a ground radial wire (I use #4 bare solid) for each tower leg and 50 - 75 ft long from each leg with ground rods spaced every 2X their height.  Also is the tower is somewhat close to the SPG, then a wire from any leg radial should be run and connected to that.

2. Coax shields should at least be connected to the tower at the base and somewhat optional if you want to connect them at the top (I understand that I may have to replace the coax run up the tower.)  ALL cables that enter the house should have arrestors located right at the entrance to the house and connected with a very short run to your SPG (single point ground).  I mount my arrestors in Hoffman electrical boxes and actually have three rods spaced two feet apart since I have more than one boxes full of arrestors (lots of cables).  This applies for rotator control, etc.  Everything.

3.  SPG kinda described above.  For the poster who had all his cable entering underground, I've seen folks that had mounted their arrestors on a large copper panel inside on the foundation wall and then ran a large diameter (always solid never stranded and copper strips 2-4 inches wide are also OK) wire back outside to their SPG.  If your cables come to the house overhead, then they should all drop to the ground to the arrestor boxes and SPG and then enter the house however you want, either at ground level or run back up to a 2nd floor shack.

4.  All of your equipment should have their ground connections tied to a buss bar (I use a piece of 1/2 copper pipe mounted along the back of the desk, and then a large diameter (don't use braid) wire run outside to the SPG.

5.  Run another wire outside (avoid sharp bends) the house and connect to the electrical service entrance ground rod.  One can drive additional ground rods along this run.

I use #4 bare solid wire.  All outdoor connections are CadWelded (which is preferred over mechanical since no maintenance).  I also use ICE (Industrial Communications Engineers) devices rather than PolyPhaser.  This is what consitutes a properly designed and installed system.  All parts must be in place as described or else Mother Nature may bite you.

Oh, I guess there is a sixth part; good homeowner's insurance. 

Hope this helps.  

Phil KB9CRY