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« on: November 22, 2020, 1622 UTC »
The biggest contributor to poor ground systems is failing to understand/comprehend *why* we are grounding. You may be grounding something for lightning protection, RFI/EMC, electrical safety, EMP, etc. - but we still call it “grounding” even though the requirements and methods may be totally different (and possibly at odds with each other).
For instance, the NEC says that an electrical safety ground is not required to use larger than #6 wire....but that would be totally inadequate for grounding a tower leg. The electrical safety ground wire is sized to ensure sufficient current flow so that safety devices like fuses and circuit breakers will function as they should. The tower ground wire is supposed to carry most of the lightning surge current to ground.
RF grounds are very much frequency dependent and as Chris points out you have to pay attention to how long they are.
You can’t lose track of legal requirements. It is possible to install something that is fully code compliant (and kosher with your insurance company) but doesn’t fix your problems, and vice versa.
There is a wealth of excellent and free military, FAA, and NASA pubs on the internet that discuss this in depth...so many that it will overwhelm you.
It is no wonder so many people have problems with grounding....but the first step to success is understanding WHAT you want to accomplish and the WHY of what you are doing.
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