I recently had a lighting strike and lost about $1000 worth of equipment. I’d like to reduce the chance of that happening again so I’m looking for advice.

I have a UDM in my house, with a 125 foot run underground in conduit to my barn. In the barn, I have a POE switch that feeds 10 cameras and an Ubiquiti AP. I’d like to add a ground somewhere. I just purchased a surge protector with ethernet for the barn, since the switch is currently plugged in directly to an outlet and should be protected anyway. I also bought this from APC for my equipment in the house. I was going to install that between my UDM and POE switch in the house, then ground it to an outlet.

I’m reading so much information about how to go about this. My barn is powered with 220v from my house, so 4 wires go to the barn H/H/N/G. the ground on the barn is the same ground as the house. If I use both devices can that create a ground loop in the event of a surge? I’m also reading that I can use the APC at any point on my network to provide protection. Is this correct?

Please don’t suggest fiber runs, as the cable is already run and I don’t plan on redoing it. Thank you all in advance.

  • deepspace1357@alien.topB
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    8 months ago

    Years ago when I was an alarm guy I had a building on 35th Street that was constantly hit by lightning and thus burning my alarm panel out. I did everything in the manufacturer recommended to earthing diodes and surge suppressors and the like ,nothing worked. A conversation with a telephone person resulted in the solution. This was in the day when the alarm systems were tied to the phone line. He told me just to tie a simple knot in the telephone cable tying my alarm to the phone, on the basis that it would slow down the surge so that it could ground elsewhere. I went from replacing the alarm control every 8 or so months to not having to ever replace it again for the next 3 years.

  • Supergrunged@alien.topB
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    8 months ago

    DITEK was the stuff I used to use in the field. Protected equipment, but they’re throw away surge surpressors. Once it’s fried, replace.

    As others have suggested, lighting rods. And the ground you’re refering to? I’d suggest driving your own ground at the barn, seperate from the electrical for this system you’re grounding to.

    There’s stuff out there to protect your equipment, but you’ll be replacing it many times over if you don’t go the lightning rod route. I know from first hand experience, as I hope someone else doesn’t have to watch a 66 block light up in your face, while working on it, due to a lightning strike.

    • westom@alien.topB
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      8 months ago

      A protector that fails is no effective protection. Even over 100 years ago, protector meant no damage from any surge - including direct lightning strikes. Effective protectors do not fail. Profit centers do.

      After a lightning strike, does a telco replace 10,000 or 30,000 protectors on all those incoming wires? Of course not. They do not waste vast sums on puny (high profit) protectors.

      Same applies to effective protection routinely implemented by informed homeowners. For about $1 per appliance. To protect from all surges including direct lightning strikes. But and again, only if that protector connects low impedance (ie less than 10 feet) to what is doing all protection. To the only item that harmlessly dissipates hundreds of thousands of joules.

      Protector (if not promoted by swindlers) remains functional after many surges - including direct lightning strikes. With specification numbers that say so. Proven all over the world for over 100 years.

  • ralf1@alien.topB
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    8 months ago

    Whole home surge suppressor in panel is worthwhile - not sure where lighting got in but it’s sub 100.00 item that you can install yourself if you have any level of electrical skill. Or the the main before you do it

  • TiggerLAS@alien.topB
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    8 months ago

    Don’t mess around with grounding. Its not going to help.

    Here are two possible solutions:

    Get two sets of these (4 total units), and put a pair in your home, and a pair in your barn.

    https://www.amazon.com/dp/B099JF9KJD/ref=sr_1_4

    Then, link the boxes together with a short patch cord:

    https://www.amazon.com/dp/B01LZ33Z9F/ref=sr_1_3

    So:

    Home > Media Converter > fiber patch cord > Media Converter > To barn

    and. .

    Barn > Media Converter > fiber patch cord > Media Converter > To home

    If lightning hits, it may burn out one or two of the media converters, but the fiber link between the media converters will prevent the ESD from propagating to the equipment in your home, and your barn.

    Obvious caveat: Depending on how close the strike is, it could still enter your equipment via other means.


    Or, if you have line-of-sight between your two buildings, you could eliminate the cabling entirely, and use a pair of UniFi LiteBeam 5AC or Unifi GigaBeam adapters, to form a wireless link between the two buildings.

    • westom@alien.topB
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      8 months ago

      Boxes powered by an electrical source means protection is gone - compromised.

      All over the world even over 100 years ago, copper wires were connected to effective (earthed) protectors so that even direct lightning strikes caused no damage. So effective that damage from lightning is routinely considered a human mistake.

      If lighting burns out one media converter, that solution is bogus.

      Effective protection all over the world (even 100 years ago) meant direct lightning strikes without a surge anywhere inside.

      Electronics atop the Empire State Building are struck, typically, 23 times annually. Electronics atop the WTC - about 40 times annually without damage. How can this be when wild speculation says something different?

      Or learn from the IEEE. Properly earthed solution is only 99.5% to 99.9% protection. So it is not perfect. Then the IEEE (being an honest and professional organization) says this:

      Still, a 99.5% protection level will reduce the incidence of direct strokes from one stroke per 30 years … to one stroke per 6000 years … Protection at 99.5% is the practical choice.

      Best protection is routinely on copper wire between buildings. If earth grounds at both ends are properly connected. Either directly or via a protector. Best solution costs tens of times less money.

      • TiggerLAS@alien.topB
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        8 months ago

        I love the (close-but-no-cigar) citation of the IEEE document titled “Grounding of Industrial and Commercial Power Systems”, which primarily deals with lightning protection for industrial and commercial buildings, equipment, power substations, and the like.

        It’s a good read, if you like air gaps, Faraday cages, and even makes mention of using lasers and rockets to dissipate storm clouds.

        Every household should have their own rocket launcher. :-)

        No mention of communication cabling whatsoever.

        In fairness, section 2.7 does deal with interior wiring systems, but it defers to the NEC with regards to adequate grounding solutions, and, in the first few paragraphs of section 2.7.1, it clearly states:

        “Basically, the NEC designates minimum acceptable limits for safety that may not be adequate for a particular application and may not necessarily provide for the efficient or practical use of high technology utilization equipment

        So, the IEEE defers to the NEC standards with regards to proper grounding/protection of interior wiring, and states that the NEC guidelines “might not be adequate for protection of high-technology equipment.”

        So, there’s that.

        Yeah, OP could put some ethernet arrestors on both ends of the cable, and then of course bond each one to a grounding source where the cables enter into each building. There are plenty advertised online, many of which come with their own sets of negative reviews after the devices failed to do their jobs, with a few of the reviewers being adamant that they followed the proper grounding procedures.

        That of course doesn’t mean that some other factors weren’t in play, but it is certainly enough to raise suspicion, while simultaneously raising enough doubt to conclude that the devices might not offer reliable/predictable protection, even when installed correctly.

        The IEEE 99.5% rule doesn’t come into play here, as it only covers unrelated grounding scenarios, and doesn’t apply to the real-life performance of the lightning arrestors themselves.

        While some arrestors may have failed at their jobs due to incorrect grounding methods, the folks that claimed to have closely followed the included grounding instructions may very well have had a defective unit. Perhaps bad solder joints, a GDT that was compromised due to rough handling during shipping or from too much heat during soldering, or some other internal flaw.

        Sadly, there’s not a convenient way for home users to test them, other than the “wait and see” method. Not the best way to find out. :-/

        As with any gas-in-a-tube device, leakage can develop from sudden impacts to the chassis, or simply from the passage of time, etc. Once the gas is gone, so is the protection for that conductor, and you only need one to fail for catastrophic results.

        I wouldn’t expect to see a manufacturer’s analysis of failure modes and failure rates anytime soon. . . Heheh.

        However, you did bring up an interesting point that gave me pause.

        “Boxes powered by an electrical source means protection is gone - compromised.”

        So you’re positing that lightning could induce a current flow in the underground cable, which will enter into the first media converter via ethernet, through its electronics, and then out to the building’s electrical system via the converter’s AC-adapter, where it will then enter the AC adapter of the second media converter, proceed through its electronics, and out to whatever ethernet device it is connected to.

        I can actually envision that path, but can’t even guess at the likelihood of that happening, any more than I could speculate on the failure rate of ethernet lightning arrestors, or the longevity of the gas-filled tubes inside them.

        Either event seems possible, and is a matter of percentages.

        Thanks for giving me things to ponder. . .

        • westom@alien.topB
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          8 months ago

          Fiber converters only do something useful when all other incoming wires (especially AC) have well proven protection as implemented over 100 year ago. If every other incoming wire is not properly earthed, then irrelevant is whether a data cable is fiber or copper.

          Surges are not induced. Surges are (for example) lightning’s current incoming and outgoing. A direct connection.

          Lightning current (a connection from cloud to distant earthborne charges) is even incoming on buried wires. As this Tech Note clearly demonstrates. Even underground wires can be part of lightning’s current path. As demonstrated in the 1950s when telcos did research for COs. That would be filled with germanium transistors.

          Surges (including lightning) are always a direct current flowing in and out between two charges. For lightning, a path from charges in a cloud to charges (maybe four miles away) in earth. That path must not connect anywhere inside a structure. For surge protection to exist.

          Concepts (also defined elsewhere by the IEEE) dictate a “single point” ground. And when properly earthed, the protection is 99.5% to 99.9%. From all surges - especially direct lightning strikes.

          For example, lightning struck a tree. That electric current went 100 feet underground to the building’s earthing electrode. Up into the house. Through appliances. Then out so earth via electrodes on the other side. Then that current flowed some four miles to distant charges.

          Damage because a best path to those distant charges was up through appliances in that house. Damage because earthing was not single point.

          Only wild speculation claims E-M fields at that tree caused damage 100 feet away. Surges are always a current that directly flows through a structure to cause damage. For lightning, damage is in the path that connects a cloud to distant earthborne charges.

          Why were church steeples damaged? Even wood is an electrical conductor. But not a very good one. So wood is damaged. Franklin’s lightning rod (like all surge protection) was only a more conductive path to distant earthborne charges. Protection is always and only about providing a better path, outside, so that surge currents are nowhere inside.

          In another venue, they had Fios - fiber optics. Lightning struck cause damage to various networked appliances. Fios ONT also was damaged. How can this be? It is a fiber converter? They did not have properly earthed protection on every incoming wire. So a direct lightning strike out at the pole flowed destructively through the ONT (fiber optic box) and other appliances. To connect to distant charges.

          Surge damage is always about the current path into and out of a structure. Protection only exists when that current has a path that need not go into the building.

          Box (Fios ONT) “powered by an electrical source means protection is gone - compromised.” Protection only exists when every incoming wire connects to the same earthing electrodes. Either directly or via a protector. Those connection to and earthing electrodes require most all attention. Virtually all professionals say that.

          NEC only defines a barest minimal earthing.

          Regarded as legendary are Polyphaser’s application notes that discuss this extensively. In one note, lightning struck the manhole cover. Which connected lightning destructively underground into a communication building maybe hundreds feet distant. Not damage induced by induced fields as so many only wildly speculate. Damage is always about where that direct strike current flows. Its incoming and outgoing path. Even on underground cables.

  • RedFive1976@alien.topB
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    8 months ago

    Please don’t suggest fiber runs, as the cable is already run and I don’t plan on redoing it.

    You said you have conduit, right? Running fiber would literally be as easy as: unplug Cat6 -> tape fiber to end of Cat6 -> pull on other end of Cat6 -> done. If that takes you 5 minutes you’re pulling too slow. Then, just throw on a couple of SFP adapters and you’re solid. No more worries about ground loops, greatly reduced chance of a lightning strike frying equipment on both ends. I think that’s worth a few minutes spent pulling fiber.

    • Thesonomakid@alien.topB
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      8 months ago

      You know that depending on the optical cable being used, grounding is still very much required, right? If this were my project and I was running underground cable to a barn, I’d use armored fiber cable to prevent rodent damage. Even if the cable is in conduit. Gophers and moles are the worst. I’ve had them chew through armored and loose tube fiber that was in conduit - which is why I will always go with the harder to destroy stuff.

      There is a lot of conductive fiber optics cable, with armored being just one type. Hence the reason NEC § 770.100 requires conductive fiber optics cable be bonded. We know it’s not the fiber that is the problem - it’s the metal that is part of the cable’s construction that will conduct electricity.

      • elgavilan@alien.topB
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        8 months ago

        The difference between running cat 6 and what you’re talking about is that armored fiber optic cable does not have to be electrically connected to the equipment at both ends. Ground loops and lightning propagation isn’t a problem with fiber, conductive or not.

        • Thesonomakid@alien.topB
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          8 months ago

          Depending on your local building codes and whether they adopt the NEC for electrical safety, bonding some types of fiber is not an option, it’s required. For reference, see NEC § 770.100. Notice the use of the words “shall be bonded or grounded”.

          The advice being given by some posters is to go with fiber like it is some way to get around bonding/grounding requirements. Thats not entirely true. Depending on the type of fiber, it must be bonded as fiber often has metallic tracer wire and armor that is part of its construction.

          Because OP mentioned that it’s an underground run between a barn and a house, I would personally use armored cable. Rodents will eat through conduit and cable. I’ve replaced and repaired miles of feet of cable due to rodents - even armored cable in conduit. Rodents are persistent.

    • planemanx15@alien.topOPB
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      8 months ago

      The conduit is the easy part. Once the cable enter my house its behind a finished wall, into my attic, and down another finished wall where it enters my basement. I’d have to remove a bunch of sheetrock in the house since its stapled along the way. On the barn side I have the same issue being behind finished walls.

  • westom@alien.topB
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    8 months ago

    You have assumed the word ‘ground’ without an always required adjective. Numerous grounds exist. For transient protection of appliances, only ‘earth’ ground matters.

    The concept first demonstrated by Franklin over 250 years ago. Surges (lightning is only one example) are hunting for earth ground. How that current connects to earth defines damage.

    A most common incoming path is AC mains. Once anywhere inside, then that transient hunts for earth destructively via appliances. A most common destructively path is into networked hardware on AC mains. Then out to earth via networking hardware.

    Damage is often on the outgoing path - ie an ethernet or HDMI port.

    If any wire enters without making a low impedance (ie less than 10 foot) connection to single point earth ground, then protection is compromised.

    Protection only exists when a surge is not anywhere inside.

    Ethernet must make that low impedance (ie hardwire has no sharp bends or splices) connection via a protector. Coax cable has best protection without any protector. Only a hardwire makes a low impedance (ie less than 10 foot) connection to same earthing electrodes. Every wire inside every incoming cable (without exception) must make that earth ground connection.

    How good is protection? Defined by that connection to and quality of earth ground electrodes. Wall receptacle safety ground is all but disconnected - never is an earth ground. Number of electrodes may be dependent on factors such as geology.

    Products from APC do not claim effective protection. One need only read specification sheets. How does its hundreds or thousands joules ‘absorb’ a surge that can be hundreds of thousands of joules? How do 2 cm protector parts ‘block’ what three miles of sky cannot?

    Scams target consumers who ignore these and other numbers. No protector claims protection. Either it makes that low impedance (ie hardwire not inside metallic conduit) to single point earth ground. (All four words have electrical significance.) Or may give a surge more paths to earth via nearby appliances.

    Type 3 (plug-in) protectors cannot be anywhere near earth ground. To not try to do much protection. To avert what tiny joules protectors do - fire.

    Don’t take my word for it. Professionals have been both saying and doing this stuff for over 100 years. Only recently have companies such as APC been selling magic boxes to consumers who ignore numbers and all this well proven science.

  • bchiodini@alien.topB
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    8 months ago

    A $30 surge suppressor will not prevent this from happening again. You can see the fakespot review, for what it’s worth.

    Even a nearby lightning strike will overcome surge protection.

    As far as I know and have seen, eliminating the path for the conducted radiation is best, if not the only, way to prevent problems in the future.

  • techsavior@alien.topB
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    8 months ago

    I have to second u/RedFive1976 about the importance of outdoor-rated fiber between structures, especially if the unshielded Ethernet cable is parallel to the power line running out to the barn. The elimination of EMI-related attenuation alone makes the switch worth it.

    • Thesonomakid@alien.topB
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      8 months ago

      If this is your recommendation, it would help the OP if you specified a good quality non-conductive fiber optic cable. There are conductive fiber optics cables in this world, and it is required that they be bonded. Thats why NEC §770.100 was written.

      Personally, because I’ve dealt with a lot of rodent damage in my career, I’d use an armored (conductive) cable for an underground run as rodents will chew through conduit. Armored fiber optics cable is designed for exactly these type of situations, and must be bonded.

  • FakespotAnalysisBot@alien.topB
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    8 months ago

    This is a Fakespot Reviews Analysis bot. Fakespot detects fake reviews, fake products and unreliable sellers using AI.

    Here is the analysis for the Amazon product reviews:

    Name: APC PNET1GB ProtectNet Standalone Surge Protector for 101001000 Base - T Ethernet Lines

    Company: APC

    Amazon Product Rating: 4.3

    Fakespot Reviews Grade: C

    Adjusted Fakespot Rating: 2.9

    Analysis Performed at: 08-23-2020

    Link to Fakespot Analysis | Check out the Fakespot Chrome Extension!

    Fakespot analyzes the reviews authenticity and not the product quality using AI. We look for real reviews that mention product issues such as counterfeits, defects, and bad return policies that fake reviews try to hide from consumers.

    We give an A-F letter for trustworthiness of reviews. A = very trustworthy reviews, F = highly untrustworthy reviews. We also provide seller ratings to warn you if the seller can be trusted or not.

  • 1sh0t1b33r@alien.topB
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    8 months ago

    You should, at minimum, have a surge protector. But not much will help if lightning actually hits your line. I mean… it’s going to roast.

  • andyring@alien.topB
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    8 months ago

    First off, is the barn system itself grounded?

    If not, it does indeed need to be per the national electric code (assuming you are in the US). That would mean two separate grounding rods installed at least six feet apart.

    • westom@alien.topB
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      8 months ago

      National Electrical code defines human protection. Says nothing about appliance protection. Two electrodes is an absolute minimal only to protect humans. Relevant are factors such as geology; that may make those electrodes insufficient.

      Does not matter if chassis ground, virtual ground, equipment ground, or motherboard ground exist. Only ground that does appliance protection is single point ‘earth’ ground. Word ‘ground’ without that preceding adjective implies one who does not yet understand how to protect from all surges, including direct lightning strikes. Knowledge that was well understood and routinely implemented even over 100 years ago.

      An honest solution will always answer this question. Where are hundreds of thousands of joules harmlessly absorbed?

  • nlj1978@alien.topB
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    8 months ago

    The barn 100% needs its own ground rods tied to the panel you tied power to. Depending on what the “barn” is you may have additional grounding that needs done. My outbuilding for example is a pre engineered steel building. I needed to bond the building to ground as well.

    Get an electrician to evaluate your barn electrical installation.

  • persiusone@alien.topB
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    8 months ago

    If you cannot use fiber, which is the obvious solution, I’d recommend a wireless solution.

    Grounding is not going to fix this issue.

    • westom@alien.topB
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      7 months ago

      Copper wires without damage even from direct lightning strikes have always been a best solution even over 100 years ago. This sub has one so ignorant as to not know this. Cannot dispute it. So he cheapshots - downvotes.

      Ground has always been the solution. However which ground? Your house could have 100 electrically different grounds. Word ‘ground’ must always be preceded by a relevant adjective. Neither digital ground, floating ground, nor wall receptacle safety ground does any such protection. All over the world (today and over 100 years ago), even direct lightning strikes did not cause damage. But only when ‘earth’ ground was properly implemented.

      Many urban myths are posted. What most call surges are only noise. Always made irrelevant by what exists inside all appliances.
      Some even foolishly call an outage a surge. Connecting IT equipment to safety ground does not avert surge damage. Nor addresses other electrical noises. Fiber does not solve the problem. Since fiber converters are connected directly to the most common sources of surges - AC electric.

      Stated repeatedly was what professionals say. With numbers. Tweets (ie use fiber) without any reasons why is classic junk science. Easily promoted because it is a tweet - does not say why.

      OP need only do what is found inside every communication switching facility (ie COs) all over the world. Since those suffer about 100 surges with each thunderstorm. And no damage. Homeowners implement same (inexpensive) solution. For protection from all surges including direct lightning strikes. Since a home might suffer one surge in seven years. Again, numbers.

      Notice: not even one can dispute the science. Or contradict numbers. First indication of someone who knows this stuff, professionally, maybe even before others were born.

      • persiusone@alien.topB
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        7 months ago

        We are not talking about high voltage telephone equipment.

        The switches in telcos are totally different than low voltage Ethernet with sensitive transcivers.

        Grounding differential potential between structures, even just a few feet apart, is often enough to destroy Ethernet transceivers without lightning strikes or surges.

        Notice: I’ve been in IT and telco for over 30 years. I have worked on Nokia telco switching equipment and can 100% tell you that Ethernet transceivers will absolutely be destroyed with much less effort than telco.

        • westom@alien.topB
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          7 months ago

          What high voltage telephone equipment? Telephone hardware is low voltages just like networking voltages. Why would ethernet transceivers be in hardware? Low voltages.

          We are now discussing people who invent lies - to sound honest. Ethernet transceivers are required to be some of the most robust. Will withstand 2000 volt transients without damage. Some are even more robust.

          We engineers constantly deal with IT people. Who know as much about computer hardware as a taxi cab driver knows about V-8 engines.

          How many computers have you designed? Not assembled. Designed by first drawing schematics. My first design was over 45 years ago. Stop trying to claim knowledge. Your examples are disinformation.

          Anyone with minimal IT and computer knowledge knows telephones are low voltage. Ethernet ports are among the most robust ports in electronics

          Only the most electrically ignorant constantly promote expensive magic boxes. You don’t even know that lightning protection is compromised (bypassed) because converter connect to AC mains. But then you are an IT guy. Who has no idea how robust hardware really is.

          Has no idea that direct lightning strikes all over the world, over 100 years ago, caused no damage to low voltage hardware (ie telephone equipment) when and because earth ground was properly implemented.

          Please stop claiming superiority using ‘IT’ as proof. If informed, then stated is why ALL professionals required low impedance connections to earth ground. So that surges (including direct lightning strikes) cause no damage. Cited professional sources. What have you posted? Technical lies justified only by hearsay and tweets.

          IT people, so often, have no idea how a computer or electricity works. A perfect example of ignorance is “high voltage telephone equipment.” The lie suggests knowledge only as a salesmen or accountant for Nokia.

  • PaulEngineer-89@alien.topB
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    8 months ago

    I think you need a much better understanding of surge protection and lightning protection.

    The first thing to look at is the passive protection. If you have a grounded metal structure anything within a 35 degree angle from the highest point is protected. It is slightly better, Google “rolling sphere” model. You need at least 2 ground rods and stranded grounding cables running to the ground rods. Do NOT share with the electrical ground and stay at least 10 feet away. Run fiber, NOT copper between buildings. If you can’t there are special surge arresters using PIN diodes or GDTs but it’s not ideal. Put one at each end.

    That takes care of protecting against direct strikes. The rest is dealing with indirect strikes Put surge arresters on ALL attached lines…power or network. Keep in mind you get about 20 V of rise per inch away from the surge arrester so they really offer very little protection more than a few feet away. Standards test equipment against surges at a peak voltage equal to twice the nominal (marked) voltage plus 1,000 V

    This also protects against switching surges that are far more common compared to lightning strikes.