Good Ground Systems are Expensive

This article does not constitute advice. Please consult an engineer or professional if you need help.  I read the excellent ARRL book Grounding and Bonding for the Radio Amateur to get my inspiration for the ground system I am going to describe.

I’m using the word ground system for a reason.  I’m trying to accomplish multiple things by improving my station ground system:

  • AC Safety
  • Lightning Protection
  • RF Management

I want to show one diagram from W8JI’s website below.  It’s important because it is a reasonable proxy for what I’m trying to do.  See below.

Background:

  • There is no economical way for my feedlines to come in to the house next to the utility entrance, so my feedline entrance is separate than my utility entrance (where my power comes in).
  • My house’s AC service ground rod is in my basement.

What I decided to do:

  • Currently, I have one master feedline that goes out from my basement shack to a 4 position switch.  Just before the run hits the switch, I pass the run through a UHF-UHF bulkhead box that has a 5′ ground rod beneath it.  The attachment is done with #6 AWG wire.  My 43′ vertical also has 2 x 5′ ground rods beneath it bonded to the radial field of the antenna.  The goal of these ground rods is to keep as much energy away from my house, in the event of lightning hitting an antenna or nearby area.
  • I have three Alpha-Delta lightning Transi-Traps on the feedlines (one spare, one for HF described above, and one for VHF antennas).  The Transi Traps are rated at 2KW and are able to pass DC as I use DC for antenna switching.  These are located at my basement feed-line entrance. Each one has its’ own 5′ foot ground rod.  All the rods are bonded together.  The goal of these is to shunt off transient energy before it gets to the radios.
  • The Transi-Traps entrance point is bonded to the Utility AC service ground rod that is some 40ft away in the basement via #6 AWG wire (even if I brought the feedlines into the utility entrance. The Utility AC service basement ground rod is in a remarkably inconvenient location from both the service entrance and the feedline entrance (and about 50′ further from the antennas than the feedline entrance).
  • I also employ a perimeter ground loop.  The loop is 175′ of #4 AWG Copper wire. It is bonded to both the feedline entrance point and the AC service entrance.  The depth is about 12″. At the AC service entrance, I am using the same path to ground that the phone & internet companies are using to get to the AC service ground rod in the basement, via a small bus bar outside of the house with small gauge wire. The idea here is that based on a lightning strike to the antennas or the power lines without a perimeter ground, I may just be partially diverting the energy.  It’s my Alamo.  I’ve got more to do to beef this up – getting a professional to add heavy gauge access to the AC service ground rod (I have yet to price this out).  Another improvement will be to add more ground rods to the perimeter ground.
  • Each piece of equipment I have with a ground connection is attached to the system (Transceiver,  Power Supply, Antenna Tuner) via a short run of copper braid.  They all run to one point on a 2′ stand-alone copper pipe bus bar where they are firmly secured with hose clamps.  This bus bar is bonded to the run that goes between feedline entry ground and AC service ground.

Materials totaling $517:

  • Transi-Traps.  $55.00 x 3   =  $165.00
  • Ground Rods.  $12.00 x 6 =  $72.00
  • Ground Rod Clamps  $5.00 x 8  = $30.00
  • 100′ of #6 AWG  $75.00
  • 175′ of #4 AWG  $125.00
  • 2′ Copper Pipe Bus Bar  $20.00
  • 30′ of 1/2 inch copper braid  $30.00

 

Houseground-best

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