I realize 99% of the internet are experts on electricity, lightning and grounding concepts, most of the internet wears a lab coat at all times, but seriously… I need a 100’ run of buried ethernet (likely direct burial 24" deep) from my house to my shed that has no power, for PoE camera & AP. Companies like APC sell ethernet surge protectors, other than biased unfounded fear, what are real world implications of a nearby lighting strike if things are properly grounded (full 6-8’ grounding rods outside each building etc…).

I feel like it’d be perfectly fine and if not, oh well, a router gets fried or wire burns up in the ground, doesn’t seem like a big deal on the off chance of real close strike or is that just me?

  • Downtown-Reindeer-53@alien.topB
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    10 months ago

    Maybe you’ve seen this already: https://www.truecable.com/blogs/cable-academy/when-lightning-strikes-ethernet-data-cable-and-lightning-protection

    I’m of the persuasion of your second paragraph. I don’t take any special precautions with what I inherited (the cable is a direct-bury with 2x coax and 2 x CAT5E. I figure if something hits nearby there are going to be a lot of problems. (A disclosure we were given when we bought our house - lightning hit the well head something like 15 years prior!

    I agree with the great suggestions by u/RedFive1976 in terms of what you can reasonably do.

  • TheRealFailtester@alien.topB
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    10 months ago

    I’ve yet to see one stop 100% of a close lightning strike, but I have seen it reduce damage a good 100x on the other side of it vs. before it. I see boxes with covers blown off full of black soot, vaporized copper wire, and charred circuit boards on the half upstream of a surge protector outside of a building, and then the half on the inside of the building that is guarded by the surge protector just has a few blown SMD compontnes on the circuit board which still fried the equipement inside as I tried to replace those parts and found the traces in the layers of the circuit boards got fried too.

    So everything still got fried anyways, but the damage was suppressed a lot by the surge protector in-line of the ethernet. It stopped a fire from possibly starting in the building by stopping a lot of the blast inside of equipment.

  • RedFive1976@alien.topB
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    10 months ago

    For one thing, everyone’s going to tell you not to directly bury cable on a run like that – bury a conduit, run it into the buildings on both ends, then pull the cable through it. And use metal conduit.

    For another thing, everyone’s going to tell you that you should use fiber for the run, but since there isn’t power at the other end, that will be a problem unless you can also run power out there (but use a separate conduit for that).

    That said, I’ve seen ethernet surge protectors installed on lines coming down from poles where long-distance WiFi transceivers were mounted, clamped to an appropriate ground. If you use buried metal conduit, it’ll take care of most of the shielding and grounding issues, and if you don’t have anything in the way of an exposed outdoor pole, you shouldn’t have too much issue with direct lightning strikes (in my opinion).

    While you’re burying conduit for a couple of ethernet runs, make it large enough for 4-6 runs, and then bury another one maybe a foot away (but check with reputable electricians) for a future electrical upgrade to the shed. You might not be able to do anything now, but at least you’ll be ready to just push some electrical wiring through in the future, and you won’t have to dig up your ground again.

  • westom@alien.topB
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    10 months ago

    Routine all over the world is effective surge protection even from direct lightning strikes. But only when one understands a protector is not doing any protection. It is only a connecting device to what does ALL protection.

    Separate buildings; each must have its own single point earth ground. Protection only exists when each wire in every incoming cable connects low impedance (ie less than 10 feet) to what does all protection. Earthing electrodes.

    Some wires can make that connection directly. Best protection has no protector. Other wires (ie PoE, AC electric) must make that connection via a protector.

    If any one wire violates that rule, then all protection is compromised. If anything fails (router, protector, light bulbs, UPS, digital clocks, etc) then a human has created that damage. Protection from all surges (including direct lightning strikes) has been that routine and well proven for over 100 years.

    Companies that sell magic plug-in boxes never claim protection. This is, too often, what such magic boxes can do. Anybody can see why by simply reading specification numbers. How does its puny hundreds or thousands joules ‘absorb’ a surge: hundreds of thousands of joules.

    Effective protectors never plug-in. Since plug-in protectors have no earth ground. Wall receptacle safety ground clearly is not earth ground.

    Effective protectors connect low impedance (ie less than 10 feet) to that earth ground. With numbers that define protection.

    One can sell a $3 power strip with five cent protector parts for $25 or $80. An obscene profit margin that pays for a massive disinformation campaign. Or one earths a ‘whole house’ protector for about $1 per appliance. With numbers that actually claim protection

    Profit centers are measured in joules. Effective protector for the incoming AC is measured in amps. Lightning (one example of a surge) can be 20,000 amps. So a minimal protector is 50,000 amps.

    For ethernet, Ubiquiti is simply one of so many proven protectors. To connect all PoE wires to earth only when a surge exists. Because and again, only earth ground does any protection. Effective protectors ALWAYS connect low impedance (ie hardwire has no sharp bends or splices) to what does protection. Each structures single point earth ground. Those electrodes require most all attention.

  • Mau5us@alien.topB
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    10 months ago

    From my experience with strikes the cable remains fine, but the ends and the equipment attached to it will likely fry. Always try and isolate and ground your lines before they enter the house so on the exterior wall it should be grounded to earth.

    • Opening_Career_9869@alien.topOPB
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      10 months ago

      thanks, that’s the plan, I’ll put a surface mount box there along with a good surge protector for ethernet like the APC unit tied right to the grounding rod that will be next to it.