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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
