Aridom82
Learning addict
I want to protect my panels, is putting a lightning arrestor like this a good idea?
I own the building
I own the building
Is putting a lightning arrestor to protect my panels a good idea? See the picture
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Aridom82
Learning addict
I am going to have to look this up. I only know one type of device, one that makes sure that gets hit if a lightning is going to hit your house.
Aridom82
Learning addict
Thank you very much. My house is going to look like some kind of neo-cathedral. I am not going to connect it to the electrical or solar ground, is going to get connected by itself directly to the ground.
"Streamer Terminal" is another term for the attractors. In theory it allows a small triaxial cable to go to a high point and it helps dissipate the energy before you would have a traditional strike. The problem comes when you do actually get a direct strike the wires are not sized for it. This often happens with horizontal strikes.
timselectric
If I can do it, you can do it.
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If you intend to install any type of lighting protection. Please do it correctly. Or you are wasting your time and money. And bring your checkbook. It will be expensive.
Aridom82
Learning addict
I am trying to understand what 'do it correctly' is here
timselectric
If I can do it, you can do it.
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It's been awhile since I installed one. And am hesitant to provide detailed instructions.
You should consult with a lightning protection installer.
But, the short version is. Air terminals, lots of large specialty conductor, and multiple earth connection points. Everything is to be installed above and around (without contacting) what you want to protect.
OzSolar
Whatever you did, that's what you planned.
FWIW: I've installed several hundred solar arrays over the last 30+ years and AFAIK none of them have ever suffered any lightning damage. Ground mount, roof mount, mobile stuff for FEMA, single and dual axis trackers, etc you name it. Anywhere from a hundred watts to a few hundred KW and no solar panel have been damaged by lightning.
My 2 cents is that you're wasting your money trying to protect the panels from lightning.
However a surge induced on your system from from nearby strike is a real thing. MidNite's SPD are top notch for that.
My 2 cents is that you're wasting your money trying to protect the panels from lightning.
However a surge induced on your system from from nearby strike is a real thing. MidNite's SPD are top notch for that.
let us know what you find
OffGridInTheCity
Solar Wizard
Short answer - I protect my arrays with Midnite lightning arrestors on both the + and - of each combined string before they enter the house. I do not have protection inside the house but maybe I should.
One of the youtube channels I follow has a rural property with >100ft of cable in the ground between his array and his Victron equipment. A ground strike caused a surge thru the wire in the ground between the array and the solar shed and fried the Victron Inverter (no protection) on the one end but the panels (with protection) were OK.
I've been following this family for a couple of years and this guy is a competent, experience, Victron oriented, DIY solar operator.
One of the youtube channels I follow has a rural property with >100ft of cable in the ground between his array and his Victron equipment. A ground strike caused a surge thru the wire in the ground between the array and the solar shed and fried the Victron Inverter (no protection) on the one end but the panels (with protection) were OK.
I've been following this family for a couple of years and this guy is a competent, experience, Victron oriented, DIY solar operator.
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timselectric
If I can do it, you can do it.
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Same here.
But he didn't know anything, when he installed his big (for him) system.
I started following this family. When the other family (Beginning from this Morning), came to help him install the system. Their system is mobile, so that's why the grounding conductor was missed. And SPD's were just a guess on their part. Mostly because they just happened to be included in the combiner boxes they purchased.
OffGridInTheCity
Solar Wizard
The system in the youtube isn't mobile, it's a fixed array and solar shed. He did have a grounding rod/conductor at the shed end but he also said he thought it was inadequate and expanded the grounding at the shed side in the youtube as part of beefing up his protection for the future.
Regardless, the interesting concept for me is that he's saying a long underground wire can allow a surge due to a strong enough ground lighting strike.... and that both ends - the array end and the equipment end - need to be protected if the wire is long enough.
For example, another setup that has looooong underground wire is youtube @Wild Wonderful Offgrid between their array and solar shed.
It seems like this issue of long underground wiring + ground strike could be true, but then I wonder at the details such as wire length, depth, does conduit help? For example, my runs from the Array (with surge protection) to the house are <50ft in conduit (one underground, the other along side the house wall) but then there's another 100ft within the house itself - so 50ft outside + 100ft inside.
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Zwy
Emperor Of Solar
There isn't a ground conductor from the array to his solar shed. I mentioned it in the comments but he insisted his ground rod at the array is the grounding. We had some discussion about the video in this thread. https://diysolarforum.com/threads/zapped.64228/
hwy17
Anti-Solar Enthusiast
NFPA 780 is a whole separate book for lightning protection and the one to consult here, not the electric code.
Tulex
Solar Wizard
Lightning protection is more an effort to protect than a guaranty. And it really depends on your setting. I live in what I would call a mini holler. A small opening in a valley of trees. The trees around me are far more likely to get hit than my house. Now, if you are out in the open flatlands, you have a different story.
How it travels is also very unpredictable. When I was a kid at home, we had 3 large trees in our front lawn out in the country. Lightning hit the shortest one closest to our house. This was a tree probably 3 feet in diameter. Split it right down the trunk. We had an old fashion hand pump over a shallow well, probably 30 feet from the tree, that had a pipe going into the house. That lightning either hit both at the same time or jumped to the well, because it went up that pipe into the basement. The pipe came out of the wall a few feet from the panel box. It jumped to the panel box and actually blew breakers out of the box.
How it travels is also very unpredictable. When I was a kid at home, we had 3 large trees in our front lawn out in the country. Lightning hit the shortest one closest to our house. This was a tree probably 3 feet in diameter. Split it right down the trunk. We had an old fashion hand pump over a shallow well, probably 30 feet from the tree, that had a pipe going into the house. That lightning either hit both at the same time or jumped to the well, because it went up that pipe into the basement. The pipe came out of the wall a few feet from the panel box. It jumped to the panel box and actually blew breakers out of the box.
Begs the question, would it be better to insulate from the earth as apposed to creating a path(ground your gear to earth) for lightning to connect?
Zwy
Emperor Of Solar
Direct strikes probably nothing will help. Induced gradient however is energy that is the result of a nearby strike in wires or other metallic objects. The energy has to be dissipated to earth. Not creating an intentional path just means the energy travels every path it can find until it gets dissipated to earth.
That can be thru your wiring in your house, the inverters, PV array, basically any conductor. Creating an intentional path to earth is lower impedance and the energy will follow that path and dissapate the energy.
They say if your in the mountains, say hiking, and your hair starts to stand strait up, that you should stand on your pack and squat down making your self as low as possible while insulating your feet as far from the ground as possible. It reminds me of that famous photo of the early stages of a strike where there where these tiny leader strikes coming off of points of trees and corners of a house all pointing towards the bolt. The one that connects first gets the bulk of the strike. Just some thoughts to add.
timselectric
If I can do it, you can do it.
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Yes I know. But the guy who showed him how to set it up. Only has a mobile system. So, he didn't know anything about grounding and SPD'S.
It definitely is. I have been preaching this to anyone who would listen.
Anything outside with substantial length. Overhead or underground. (Overhead is more susceptible)
PVC conduit provides zero protection from the gradient pulse. Grounded metal conduit does provide some shielding from it. SPD's are the best defense.
If you have a high lightning hazard then mount a steel pipe in a suitable poured concrete footing and connect an air terminal to it, located ~8-10' north of the array and 4-5' higher. Run a couple ground rods from the pipe about 10' or more away-- and away from any of your equipment and the house. Don't connect anything else to it. If you want to you can put a plastic pipe around the steel pipe and down-conductor to reduce the risk of flash-over to your array somewhat.
MarkSolar
Solar Enthusiast
Security cameras where I used to work captured a lightning strike on one of the other buildings. It was a large campus with dozens of industrial buildings, the one that got hit was the only one protected by a special lightning protection system installed by a company that does that kind of thing. The strike hit one of the rods on the roof, went down the side and turned a telephone pole into a million toothpicks, arced over to the communications raceway and incinerated that, arced over to the conduit carrying the 3 phase into the building and melted that, then blew everything in site off the side of the building. In the 60 years the place has been there, no other building has ever been hit or damaged, only the one that got the expensive protection. So based on this rigorous statistical analysis of a sample size of one, if i were in your shoes, I'd spend a more money on insurance and forget the whole lightning thing.
Aridom82
Learning addict
Well, i just want to protect my panels and all, they are on the roof and they are grounded so i thinks is risky to have them just like that.
Aridom82
Learning addict
i have 6 of these installed, one per each panel strings. A SPD is a different thing?
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