Question Ethernet surge protection

[Eben D Bothma]

hi, i don't know if this is the right place to ask but help is appreciated. I recently ran an ethernet cable outdoors about 65meters and now am concerned with the possibility of a power surge ruining my pc and Xbox if I connect directly to the Ethernet so I was looking at surge protectors for rj45 and thought that maybe it would be enough using an old router (functioning as an AP) to absorb the impact of a surge if God forbid it happens. I'm willing to let a rout3er die seeing as i get my hands on them frequently for basically free.

Apologies in advance if I'm asking as really stupid question and thanks again for the help

 

[ex_bubblehead]

The kind of surge (lightning strike perhaps) releases many times more energy than any consumer level device can handle. Commercial devices capable of such run 6-7 or even 8 digits in price.

 

[bill001g]

Not really a stupid question when companies try to sell you garbage like this.

So first lightning is not a surge it will fry anything. It will travel down the plastic even in some cases. A surge is more related to the power that comes into your house and that does not apply to ethernet.

Ethernet cables by design are magnetically isolated from the equipment they plug into with tiny transformers. This is mostly to isolate the signals from the power and ground of the end equipment. In addition many devices have tiny optical isolaters before the transformers so there are 2 layers of isolation. Ethernet wire has the pairs twisted and the groups of pairs are also twisted together. Again this is to prevent interfering signals from entering but it would also prevent some kind of surge from coming in from say a power cable crossing it.

You see so called surge protection for ethernet on UPS. Hard to say what they have done but it likely does nothing and might actually introduce interference into the ethernet cables. A surge protector is small device that connects to ground. After the manufactures go to all the trouble to isolate the ethernet cables from everything connecting the leads to ground is stupid.

Lightning is a completely different thing and you could put a sacrificial switch or router in between but that does not always protect you. I had a lightning strick someplace close to my house. It seem it came in on the power. It got past mulitple UPS that have surge protection and also some surge protection strips. It also got into one of my switches and then traveled out and kill a camera connected to the switch. I don't think there is a way to prevent lightning damage other than unplugging everything. The day it happened it was just cloudy and the rain was miles away.

 

[USAFRet]

I had a lightning strick someplace close to my house. It seem it came in on the power. It got past mulitple UPS that have surge protection and also some surge protection strips. It also got into one of my switches and then traveled out and kill a camera connected to the switch. I don't think there is a way to prevent lightning damage other than unplugging everything. The day it happened it was just cloudy and the rain was miles away.

Mirrors an event I had almost exactly.

Lightning strike in/near the backyard.

Dead devices, (almost) all on individual UPSs.

UPS 1
PC - ethernet port

UPS 2
Denon receiver - HDMI port
HP printer - ethernet port

UPS 3
PC and monitors not affected.

Things were on different switches and routers.
Other things connected to those were not affected.


Other:
Long unused Invisible Fence circuit board. This was unplugged from the wall outlet. The circuit board was cooked, and the cover blown 1/2 way across the garage.

Twilight Zone moment:
Battery powered laser level, in an upstairs room. Had not been used or turned on in over a week.
I go upstairs later, and it was ON.
Read that again...battery. Sitting on a tripod in the middle of the bedroom.


Electricity follows strange pathways.