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Lightning surge protection on underground and overhead network cable 1

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sugar22

Computer
Jun 23, 2014
4
RO
thread236-328817

Hi everyone! I'm new on this forum but an old reader, great forum!

I'm going to instal my IP cameras system, most of them will be outdoor.

My big concern is about outdoor LAN network construction to limit lighting damages!

Few questions:
1. Outdoor LAN lines underground or overhead(I can do it both ways); Witch is the best option for surge protectors to work right? I am confused which option will work best!
2. Outdoor grade, grounded SFTP/FTP in plastic conduit/duct or in an grounded metal conduit/duct?
3. Probably if in an grounded metal conduit/duct an outdoor grade UTP will work?
4. Also for multiple LAN lines in the same conduit/duct plastic or grounded metal, SFTP/FTP is better do not interference with each one?


Any suggestion and experience will be great!
 
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Is using fiber for the exterior cameras an option? That would be best.

Copper infrastructure in RGS (Rigid Galv Steel) may offer some protection operating as an inductor to lightning surges.
 
From the beginning my project didn't include fiber.

PoE cameras, 8 different locations; in future will be a total of 16 PoE cameras

For network I already have:
1. Managed Poe Switch Zyxel 1910-24hp
2. 8 IP PoE cameras Hikvision DS-2CD2032-I

Next buy:
1. Surge POE protectors for each camera line one at the IP camera side and one at the Switch side
2. Ethernet cables
3. Pipes

Instead of grounded RGS (Rigid Galv Steel), grounded copper water pipes will do some protection operating as an inductor to lightning surges? Copper pipes are thin 0.7mm-1mm. Copper pipes will be ok for direct bury or need a kind of bitumen/asphalt coat?

Outdoor lines are max 30m(in which, underground/overhead max20m)
Best way to go underground or overhead?

If I go overhead I can use galvanized flexible(like spring/shower flexible conduit), but again it's thin

 
"Good luck" is about the best we'll be able to offer... if lightning hits anywhere near copper lines, there isn't a whole lot you can do to prevent damage to something so sensitive as a camera system. Anything connected to those copper lines is likely to be toast in one form or another (shortened work life, if it survives). Fiber is really the best solution here... the worst you'll typically get is a melted cable that needs to be re-run.

Dan - Owner
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What I need to add to switch from Copper lines to fiber lines? I am not say no for fiber;
But:
If I go fiber is just about protecting switch side? Camera sides will ramain anyway open to lighting, am I right? Also PoE will remain out of service, am I right? Extra power line will need also ... probably more others news :).

 
If the fibre optic cable could carry power as well as data, then it would be a complete solution. That said, it's easier to protect power circuits than data circuits. So it would be useful, but expensive.

It's worth double checking the overall business case. DVR based camera systems, including 4 or 12 or N cameras, are getting cheaper and cheaper by the year. Depending on circumstances, it might be easy to spend much more on a lightning protection scheme than the value of the entire camera system. If it's an expensive system, a critical installation or damaging lightning storms are common, then it'd be worth it.

It is feasible to design some systems to withstand direct hits. Cell phone and radio towers typically achieve this, but it's not cheap. And plastic case devices need not apply.

Search using the legacy name Polyphaser.
 
I’ve installed several of these, and we typically use either rigid metallic conduit or PVC, but always use outdoor rated (OSP) cat-5 cable. I only use the shielded Cat-5 if I’m in a high noise environment (near electrical lighting, high voltage, or variable frequency drive units). Running multiple cables together in one conduit saves on conduit runs, but does not necessarily provide any greater surge/noise protection.
Never run indoor rated cable outside, even if in conduit.

I would never run cabling in water/copper pipe. Your just asking for trouble.

I’ve run cable both underground and aerially, either work well. If you run it overhead, it should be supported by a messenger cable, and can be in ducts. I would probably not use the flexible galvanized conduit. If its OD rated cable, it can be lashed directly to the messenger cable.

The most important thing is to run the cabling through good surge protectors, as close to the building entry point as possible and connect to a good ground system.

Unless your cameras are being mounted on poles that would be the highest points in the area, I would not expect you to see a direct strike. Normally most damage I’ve seen is from nearby strikes causing induced surges. I had one camera atop a metal tank get hit and it blew the camera housing apart and the dome drive unit was found 60’ or so away. No amount of surge protection will protect the camera from a direct strike. But you can protect your back end infrastructure.

As suggested by others, fiber is your best option to protect your head end equipment. you can power the camera locally, and transport the camera feed over fiber. Since they are IP cameras, simple fiber to Ethernet converters would be required.
 
Links with examples of underground outdoor wires connections in grounded metal pipe/duct

Is there any difference between galv metal duct or copper pipes?

1. All cables should be routed from tower to the house via underground metal duct (it also has some surge choking effect).

2. Run your coax cable and control wires up inside the framework of the tower, next to one of the
legs. This way, the tower provides two types of protection. First, the tower will protect the lines
mechanically from falling/flying tree limbs, tools, antenna parts, etc (during tower work or a
storm), haul lines, or anything else that may bang into or snag on the tower. Second, the tower cage
acts like a faraday shield to help protect the lines electrically from EMP (nearby lightning) and
direct tower hits from lightning.


3. Especially since you're not using metal conduit, the cables should have lightning arrestors (eg, at both ends. These need to be grounded to a good, legal electrical ground.
 
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