Lightning masts / arrestor / poles

Does anyone know of a reputable company that can install a lightning conductor / mast. Not sure if the correct name for them.

My panels are pretty high up and are more than 300mm above the top of my roof so they are a bit like antennas. Last year I had a bit of lightning damage when my neighbors lightning rod got hit. I would prefer some damage over a direct hit.

I’ve been checking online but some sites just seem a bit dodgy so just wondering if anyone has experience with this. Ballpark installation costs, etc.

2 years ago I heard about a man sharing knowledge about lighting masts/poles etc to the insurance industry and their brokers.

Suggestion, contact an insurer/broker or two and see if you can get hold of him. From there find the right cmpany, as it is a rather interesting subject to properly cater for.

My 2 cents on this matter.

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I read on another site that panels should be earthed directly to the earth spike…
I would also like to know what best practice is.

In my research on this subject, came across these folks… have not dealt with them so this is info only…

I have done that but a 6mm cable between the panels and spike isn’t really going to do anything for a direct hit.

But the neighbors mast survived the hit last year. So the idea is to take the risk of a direct hit away from my panels.

Since your neighbor already has a mast I would not add anymore : “Hey hit me please” antennas to your area, depending on how close your neighbor is a direct strike is probably going to hit him anyway but stray lightning will come over to your side.

@Phil.g00 is a advocate for only having one central earth, he has some lightning insights since IIRC he lives on top of a mountain somewhere where lightning is all too common.

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My father had two lightning rods around the main house on the farm. It was literally just a long steel pipe of gradually diminishing diameter (because of weight and all) sticking up in the air as high as possible. I think at its highest point, after we extended the tower to hold the two-way radio antenna back in the 90s, it was close to 20 meter up. It was earthed using some bare copper wire of maybe 4mm^2, and tied to another steel pipe in the ground (not even copper).

This was about 3 meter from the back door of the house, but at least 20 meter away from the solar panels and the rest of the system.

Lightning would hit this thing repeatedly in the same evening, and everything else would survive.

But… one evening lightning struck the telephone wire some distance away, it came all the way to the house, jumped across to the corrugated iron roof plating (there was an actual burn mark where it did this), from there onto the 36V DC wiring for the lights… and it blew both the inverter and the solar charge controller. The inverter was insured…

That is to say, lightning rods are extremely effective… but need to be some distance away, and while they greatly reduce your odds of getting hit, it can still happen.

Lightning can be odd. I’ve heard stories of a young kameeldoring tree (Acacia Erioloba) being hit instead of the 12 meter windmill standing right next to it.

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Its all about dissipating the static charge, its not there for the direct strike. If you can get all your metal pieces down to the same potential then lighting will probably not hit, but i say probably as its never 100% sure thing.

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That is because those Kameeldoring trees are made of iron! And those silver seed pods are just as hard. Closest thing to a rock if you are standing between the sand dunes :grin:

What kind of arrestor does your neighbour have? (standalone pole or spike on roof??)

The topic of lightning fascinates me, I’m a radio amateur with antennas 16 meters high, so basically a nice big pointy aluminium thing just inviting lightning down to my house. I don’t claim to be a expert, but have read up quite a lot on the topic, especially since I’ll be moving to a area with even more lightning in future where I plan to put up a even higher antenna tower.

If you really want a conductor, first sit down and have a stiff dop before you start getting quotes. Basically the guys charge whatever they want because they know it’s a insurance requirement for those putting them up so a grudge purchase. Remember for the insurance to take note come claim time they also have to be SABS / SANS approved and inspected regularly, once per year if I recall.

My advice, insure your stuff and claim if you get damage, if a conductor isn’t a requirement by your insurance, then don’t put one up.

Read up on the topic, it will keep you busy for weeks, grounding and bonding, you will get thousands of opinions. If you decide to make changes to your system, aditional earthing etc. please just be sure it’s to local code and to the liking of your insurance.

P.S. Some is even of the opinion that lightning conducters is a complete waste of time and basically useless at preventing any damage, refer to what @plonkster said, if it wants to hit you, it will hit you.

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Another easy solution is to simply unplug when there is bad weather. That was another thing we did on the farm. Everything was designed in a way that it could be physically disconnected and physically moved apart. The solar panels could be completely unplugged from the system, the inverter could be disconnected from the AC-lines going to the house. The television would always by completely unplugged (from the wall, as well as the antenna connector). The two-way radio had two antennas, a shorter “storm” one with a shorter range, and the long one on top of the tower. We switched to the storm-one during bad weather.

If you went away for an extended number of days, you did the same. Disconnected anything you could. Obviously not the solar panels and the inverter, for the freezers still needed to run.

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Yes, the only sure way to prevent damage is to unplug, it quickly becomes a habit.
I get lazy in winter and generally leave my antennas plugged in, but in summer I’m always plugged out when not in front of my radios. Even quickly going to the shop or to a friend to go borrow something with clear weather can catch you off guard, got the T-shirt.

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Disconnecting equipment from the existing wiring in the house is a pain but effective. Back when we had ADSL there was no way you could protect the router from transients on the telephone line. However I saw one device which had a radio receiver that detected static discharges (lightening) in the area and physically disconnected the router from the line.
And then we got fibre :hugs: (This killed 2 birds with one stone: Telkom & POTS telephone line)

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Our new farm has thatched roof houses which we intend getting rid of in future, there is 2 lightning masts on the property.

As expected the insurance said the masts should be inspected once per year, I haven’t done it yet. The first quote I got was R800 to come out and give a CoC if it’s within spec, if it’s not within spec it will cost R5800 per mast to redo the earthing and then CoC.
The guy said he will just redo it from scratch, because of having no idea how or when it was previously done, while digging everything open to try find out, you might as well just redo it all.

Apparently it’s quite common for them to fall out of spec anything between every 3 to 5 years depending on the type of soil in the area.

Interesting, Santam say 2out of the 3 should be in place for them to pay in the event of a fire or lightning claim.

  1. A lightning conductor with valid CoC.
  2. A 4.5 kg fire extinguisher for every 200 SQM of a domestic property.
  3. The thatched rooves should be treated with a SABS approved fire retardent, also with valid certificate.

Except for the lapa, for some reason for the 8 x 8m lapa all 3 should be in place.

Cannot remember the name of the product, I think Dehn Africa can supply, but it’s a fine sand like material you distribute around the earth mesh, or add to concrete. That improves the coupling tremendously. Called Marconite: https://www.dehn-africa.com/store/p/en-ZA/F407560/conductive-concrete-moisture-retaining-clay

Groton is

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Dankie, yesterday someone also told me about a product which sounded similar to this, he said he’ll find out on Monday what it’s called.

I get that but at the same time it doesn’t make sense. I mean a lighting spikes is also at the same potential as earth and the lightning is basically finding a path to earth so if the panels are high enough, it seems it’s working the same as a spike. :frowning:

They have standalone spikes.

One company got back to me. Conductors for africa. Said that anything that falls under a 45 degree angle from the top of my neighbors spike will be fine. Unfortunately some of my panels don’t meet this. He also suggested that if I do go ahead, then I would need to make sure that my inverters and batteries are not in contact with any wall or floor as it should be completely isolated.

For a 20m spike, fully installed, I’m looking at around 20k. It obviously come with all the paperwork as well. I’m still a bit undecided. It’s not a requirement from insurance and i may be just opening myself up for more yearly maintenance costs.