Been there and played that game. About a year before I retired it was decided we needed a new sub station for our facility. I was sucked into that nightmare. Well not a nightmare for a facilities engineering type which I wasn't. I did get a crash course in power sub station ground planes and ground in general. The actual work was contracted out. This is a pretty good read on the subject. We started with soil analysis drilling out soil core samples which are sent to a lab. Then you drag in a backhoe and start building an "earth mat" with a mountain of copper bar stock. Once you create all of this you fill in the hole and built your sub station on your hallowed ground. Lightening arresters come later. We buried plenty of copper.

We only brought in 13.3 KV. The option for 25 KV was also on the table. Buying 25 KV service is a little lower cost than the 13.3 KV but the 25 KV switchgear has a much higher cost. I was looking at a 20 year cost turn around so went 13.3 KV.

While none of this has much anything to do with residential lightening it is interesting and amusing.

Ron

It sounds like one of the few cases when you need a civil engineer to help with an electrical engineering project.

It demonstrates that you can pound a grounding rod into the ground and expect it to be grounded, or you can verify it is grounded, or you can make sure it is grounded.

 

It sounds like one of the few cases when you need a civil engineer to help with an electrical engineering project.

It demonstrates that you can pound a grounding rod into the ground and expect it to be grounded, or you can verify it is grounded, or you can make sure it is grounded.

Likely why they make Earth Ground Resistance Testers. Each step of the way things are tested for compliance in an industrial project. Residential depends on any state, local or city codes and how they may choose to inspect. Most states just adopt the NEC (National Electric Code) in the US making it simple for them. Anyway, so much for lightening.

Ron

 

Even down here in the wet and sandy Coastal Georgia we Megged every driven ground rod which was typically a 5/8" 10' copper clad iron rod. More to check the connections than the rod resistivity. Here the ground water table is often only a couple of feet below the surface. Septic tanks, when installed, often have to be filled with water to prevent floating out of the ground. We often had to "de-water" excavation sites with well points and pumps to build the concrete pour forms for foundations and tank pads. I have also additionally "salted" the ground plane for a vertical multiband HAM antenna's ground rod with ground radials to improve the ground plane. My understanding of the US Electrical Code is that in rocky areas they depend on METAL water or gas supply pipes for grounding. Unfortunately, metal piping is becoming scarce in new construction and utility supplies. Even gas supply piping while metal is plastic coated for corrosion resistance.

 

Even down here in the wet and sandy Coastal Georgia we Megged every driven ground rod which was typically a 5/8" 10' copper clad iron rod. More to check the connections than the rod resistivity. Here the ground water table is often only a couple of feet below the surface. Septic tanks, when installed, often have to be filled with water to prevent floating out of the ground. We often had to "de-water" excavation sites with well points and pumps to build the concrete pour forms for foundations and tank pads. I have also additionally "salted" the ground plane for a vertical multiband HAM antenna's ground rod with ground radials to improve the ground plane. My understanding of the US Electrical Code is that in rocky areas they depend on METAL water or gas supply pipes for grounding. Unfortunately, metal piping is becoming scarce in new construction and utility supplies. Even gas supply piping while metal is plastic coated for corrosion resistance.

The best thing about 'salting' the ground is it also keeps the demons out.



An antenna farm on that sea level flat of coral was a natural lightning attractor. We were hit all the time but had MIL-SPEC suppression on every line into the station so we seldom had issues with a direct strikes other than utility power loss but we had a local generator to handle that.

 

The best thing about 'salting' the ground is it also keeps the demons out.

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An antenna farm on that sea level flat of coral was a natural lightning attractor. We were hit all the time but had MIL-SPEC suppression on every line into the station so we seldom had issues with a direct strikes other than utility power loss but we had a local generator to handle that.

That image shows the, I paid too much for this HiFi console to throw it in the bin. I'll use it as a shelf for my Sony receiver, and I'll set the Sony speakers next to this console full of speakers.

It is worth keeping both since the old console can play vinyl but they'll have to move some wires and equipment to access the phono.

 

I've never been able to afford or convince myself of the absolute need for an 80-100' Rohn antenna tower and set of beams. The guys I know down here that do have them physically disconnect the coax when not in use. One guy even goes to the effort of having that disconnect point outside of his HAM shack. I've specified the lightning suppression rods to be installed above the 100'+ distillation columns we had and never had one hit. We had huge piles of coastal plains Fat Lightered stumps that we processed into oils and resins. Back in the day (before they strung the grounding wires above them) they got hit and the fire was so intense that fire companies from several surrounding counties could not extinguish it. Acres of ~80' tall stump piles. They had to let hundreds of thousands of dollars of stumps burn out and prevent the surrounding stump piles and the processing areas from catching on fire also.