Putting Up a Tower – Grounding and Bonding

[Fred Kemmerer]

[caption id="attachment_62826" align="aligncenter" width="4028"] Proper Tower Grounding[/caption]

I made some progress on the new tower here today by installing a lightning ground system and bonding the tower to the electrical system ground at our QTH. The photo above shows how to do this. An 8′ electrical ground rod is driven for each leg of the tower and the legs are connected to these rods with heavy ground cables.

[caption id="attachment_62827" align="aligncenter" width="4000"] Bonding and Grounding[/caption]

The rod in the lower right in the first picture is then connected to the perimeter ground system which runs around our house to the ground for the electrical system by the meter in the front of the house. The bonding is essential to prevent a lightning hit on the tower from finding a path to the electrical ground through the house. The ground rods are driven to just below the surface to avoid tripping or stepping on them when working around the tower. The wire on the right side of the second photo will be connected to a coax static arrestor ground block which will be installed later.

 

[Burns FISHER]

Do you use “exothermic bonding” for the tower connections?  I see clamps on the rod, but I can’t make out how they are connected to the tower.

Also, I have heard that woven ground straps are better than heavy wire.  Any thoughts?

[Fred Kemmerer]

Hi Burns,

I use simple bolt-on ground clamps to connect the ground wire to the rods and I use hose-style clamps to attach the ground cables to the tower legs. Exothermic binding does work well but it requires some special gear to use and it only works with uninsulated cables which are often used below ground.

Straps and copper strips do work well for RF grounding and they should be used in your station to provide RF and AC safety grounding. For lightening, you need a heavy cable that can stand some high current surges so standard electrical system ground cables are best used for that application.

The work on my tower is about lightning protection and ground so the heavy electrical ground cables are the way to go there.

I hope that this helps,

 

[Burns FISHER]

Thanks, Fred!

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