More outdoor network cable damage

[Donald]

I have mentioned before I support outdoor WIFI at a church camp. For the second year in a row I found the RJ45 connector for a long outdoor run burned and no longer working. This cable goes from a telephone pole to the top peak of a two story dining hall with an attic.

In this case the RJ45 was going into a Unifi surge protector which was burned. The patch cable going out of the surge was also damaged at the surge protector. The other end of the patch cable goes into a POE injector and that was not damaged.

The other end of the outdoor network cable goes to a switch and WIFI access point on a telephone pole. Neither was damaged.

I have 10 other outdoor access points and no damage to them in many years.

And yet this one was burned two years in a row.

Surprised it did not zap hardware at both ends of the outdoor cable.

The Unifi surge protector did protect the POE injector and switches past that.

Not sure what else I can do. I mean the goal is to have WIFI across the church camp grounds which is 35 or 40 cottages, chapel, dining hall on 10+ acres. So WIFI for devices in cottages and walking around the camp grounds with phones, tablets, watches, etc.

 

[henni]

Lightning strike damage ? How is the earth ground handled ?

 

[brianl703]

Do you have surge protection on the telephone pole end of the run?

If not, you should add it, and the telephone pole should have a ground wire run up it (and coiled up on the bottom of the pole in the ground) if it was installed according to telephone company practices--you can ground the surge protector to that.

 

[Donald]

Do you have surge protection on the telephone pole end of the run?

If not, you should add it, and the telephone pole should have a ground wire run up it (and coiled up on the bottom of the pole in the ground) if it was installed according to telephone company practices--you can ground the surge protector to that.

I agree. But there is a 70 year old guy (me) to handle things. I have to do everything including climbing ladders on telephone poles.

But remember I said no damage to cable RJ45 connectors or devices on the telephone pole.

The damage was to the RJ45 inside a building.

 

[Donald]

Lightning strike damage ? How is the earth ground handled ?

The CAT6 cable from the telephone pole enters the building and is first connected to a Unifi network protector (which smells and looks burned). The ground from the surge protector is connected to ground of a grounded plug plugged into an electric outlet. I plan on running like #8 or #10 directly to a ground rod this summer.

 

[brianl703]

The damage was to the RJ45 inside a building.

Probably where it arced to ground.

 

[brianl703]

The ground from the surge protector is connected to ground of a grounded plug plugged into an electric outlet. I plan on running like #8 or #10 directly to a ground rod this summer.

Per NEC rules, if you are driving a new ground rod, you have to connect it to the building's ground (that same ground that is connected to the load center/breaker panel serving the bulding). Failure to do this will result in more blown up equipment.

If you're running #8 or #10 to the existing ground rod where the building's electrical service is grounded then that is fine.

 

[brianl703]

Also, those Unifi network protectors probably aren't primary surge protectors, but secondary ones (EDIT: Scratch that, they don't even appear to be UL listed....)

A primary surge protector is something like this:

SurgeGate - CAT6-75/POE-RJ45 | ITW Linx

SurgeGate - CAT6-75/POE-RJ45 surge protector features: Cat6 performance, fast response time (1-5ns), and solid-state protection. Ideal for various environments.

www.itwlinx.com

• Agency Approval UL Primary (497) and Isolated Loop (497B)

(There's also a version of this with a 110 punchdown connection for the outside cable, which I prefer):

CAT6-75 / 110-RJ 45 | SurgeGate | ITW Linx

Solid-state protection, ideal for primary & isolated loop applications. Perfect for CISCO POE systems, expandable for growing needs. Backed by a 5-year warranty

www.itwlinx.com

(or if you want 110 punchdown on both the outside and inside cable):

SurgeGate CAT6-75 - Single Line Protection | ITW Linx

SurgeGate CAT6 single-line surge protection with Signal Perfect Circuitry. Exceeds TIA/EIA Standards. Versatile for various applications. Full features include --

www.itwlinx.com

Primary surge protectors can handle much more surge energy than a secondary one. All incoming communication lines are required per NEC rules to have primary surge protection.

 

[brianl703]

My theory as to why the cable was burned is that your non-UL listed, non-primary protection, $12 (if I'm looking at the right one..) Unifi surge protector got hit with more than it could handle. Open it up and I bet you find burned components inside. Just be glad it didn't catch anything else on fire...

You get what you pay for. The ITW Lynx ones that are UL listed for primary protection cost more like $60 (EDIT: $100. Inflation).

 

[wwillson]

Install fiber, it's not conductive. It will cost more than running copper, but you'll be money ahead over time.

 

[brianl703]

Install fiber, it's not conductive. It will cost more than running copper, but you'll be money ahead over time.

Then I suppose he can install solar panels and batteries to run the wireless access points.

 

[mk378]

It could be I squared R heating from heavy PoE currents. I have seen it happen on professional grade parts.

 

[brianl703]

It could be I squared R heating from heavy PoE currents. I have seen it happen on professional grade parts.

It's also more likely to happen with cheap network cable that's "copper clad aluminum".

 

[wwillson]

Then I suppose he can install solar panels and batteries to run the wireless access points.

Yes, he is going to need power, but it's going to be cheaper in the long run to install power instead of losing network gear to ESD or whatever is causing the burning of the ethernet cable. Powered fiber cable could work in this application.

 

[brianl703]

Yes, he is going to need power, but it's going to be cheaper in the long run to install power instead of losing network gear to ESD or whatever is causing the burning of the ethernet cable. Powered fiber cable could work in this application.

But you'd still have to add surge protection to the power feeds. These power feeds are susceptible to surges, more so than regular ethernet, in fact--regular ethernet has 1500V of isolation built into it per IEEE spec. Ain't no isolation on a power feed unless it's AC and fed through a transformer.

 

[wwillson]

Ain't no isolation on a power feed unless it's AC

I'm talking about running 120v AC in the powered fiber cable.

 

[brianl703]

I'm talking about running 120v AC in the powered fiber cable.

Pretty sure that requires a permit, and may need to be installed by a licensed electrician depending on local regulations.

 

[Donald]

Install fiber, it's not conductive. It will cost more than running copper, but you'll be money ahead over time.

We do have fiber as a backhaul going building to building. But the small outdoor switches and access points on telephone poles are all POE powered. So the CAT6 cable brings the data and POE. With fiber I would need to run copper wire along with the fiber to bring power for the POE.

 

[Donald]

Also, those Unifi network protectors probably aren't primary surge protectors, but secondary ones (EDIT: Scratch that, they don't even appear to be UL listed....)

A primary surge protector is something like this:

SurgeGate - CAT6-75/POE-RJ45 | ITW Linx

SurgeGate - CAT6-75/POE-RJ45 surge protector features: Cat6 performance, fast response time (1-5ns), and solid-state protection. Ideal for various environments.

www.itwlinx.com

• Agency Approval UL Primary (497) and Isolated Loop (497B)

(There's also a version of this with a 110 punchdown connection for the outside cable, which I prefer):

CAT6-75 / 110-RJ 45 | SurgeGate | ITW Linx

Solid-state protection, ideal for primary & isolated loop applications. Perfect for CISCO POE systems, expandable for growing needs. Backed by a 5-year warranty

www.itwlinx.com

(or if you want 110 punchdown on both the outside and inside cable):

SurgeGate CAT6-75 - Single Line Protection | ITW Linx

SurgeGate CAT6 single-line surge protection with Signal Perfect Circuitry. Exceeds TIA/EIA Standards. Versatile for various applications. Full features include --

www.itwlinx.com

Primary surge protectors can handle much more surge energy than a secondary one. All incoming communication lines are required per NEC rules to have primary surge protection.

Thanks. I will read through. One thing I noticed in a quick read was that it only handles POE+. I need POE++. My POE injector is 60W. I have spec'ed out the cable and RJ45 connectors to be POE++. I am 99% sure the wire is not CCA. I drive a small Unifi switch and 4 Unifi access points with the one CAT6 cable.

 

[Donald]

But even a super network surge protector probably would not protect the network cable & RJ45 connector going in to the surge protector.

The Unifi surge protector did not protect the RJ45 connector going out. But it did protect the POE injector that was next in line.