Networking buildings with cat6 above ground

[Captain Pooka]

A church asked me to network their three buildings. They don't want me to bridge, they want a physical connection between all three buildings.

The old ATT guy ran their phone lines on the existing utility poles. He put some J hooks a little lower than all of the other wires and just ran his phone cable on through. This goes over a paved alleyway, by the way. T

So here's what I'm thinking:
I'm just going to put some J hooks a little above his (I read it has to be at least 30" below a transformer, if one exists). Run the cable along the poles in to a grounding block, then in to the buildings. Simple, right?
I'm thinking two runs. The three buildings make a triangle, each about 200' apart. So I'm going to have two runs, one from the modem to building 2, and one from the modem to building 3. Each run, again, about 200'.

Now what do I need to buy.. in terms of external hardware (Cable, Gounding block) and internal hardware

I'm thinking I'll just use their existing ATT modem (5port 10/100/1000), put a 100/1000 switch in each of the buildings, then a WAP in each of the buildings to supply wireless.

The ONLY thing I can find on running cable outside is underground. I need some cable that can be run on utility poles and I don't know what to buy. Can I get some help with that?
Also grounding the cable. I've never run cable I've had to ground with anything other than a grounding nut to something metal. Do I need to purchase an actual grounding block? Or some how ground it to an existing rebarb in the ground? I really need help with these parts.

Thanks for your help.

I should mention that the new ATT guy offered up some assistance. He said he would run a 12pair UV resistant cable. That way when a pair goes out I don't have to rerun cable. Makes sense. He also said my J hook idea wasn't a problem. He mentioned that I could probably just run the new cable with the existing phone cable on the existing J hooks. Any thoughts?

Thanks again!

 

[setishock]

You can't run private wiring on public utility poles. I found that out when Entergy found the previous owner here mounted a couple of cameras on their poles. They got their knickers in a serious twist.
If the att guy runs his and yours at the same time you can get away with it. Make sure the jacket is black and UV resistant. It also needs to have slack in between the hooks. If taunt when installed the cold will snap it when it shrinks up. In the warmer months it will droop some but there's no harm in that.
As for grounding the cable it's not really needed. Make sure the cable you use has a good twist ratio to it. That keeps the hum out. The best way to keep it from getting hit or getting any interference is to put it underground. Direct burial cable is pricey. PVC tubing and indoor cable work well together.

What state you in?

 

[Captain Pooka]

I'm in Texas.

Burrying it was my first go-to, but that seems to not be an option. The ATT guy and I are friends, he said go ahead and run it with the other cable, it's not a problem He also offered to come and help when the time comes. I just don't know if I need to purchase cat 6 4pair, or ... some thick 12 pair...

Amazon.com: Cat6, 600 Mhz, UTP, UV Jacket, Outdoor, CMX, 1000ft, Black, Bulk Ethernet Cable: Computers & Accessories

12 Pair 24AWG Telephone Cable - PE89 Direct Burial (Per Foot)

It all says it's for burial, but is it ok in the air? In Texas it is rarely "cold". 60s is cold down here, 40s is freezing and it happens a week or two out of the year. It does get over 100 often when we hit april - september.

You sure the cable does not need to be grounded if run above ground? From what I read Catx cable is super liable to be hit. I'm not sure how to ground it in a project like this, as the cable will go from the utility pole in to the building at the top of the building.

Someone ran Catx cable (indoor) along the outside of the building, not sure what they were thinking. When I asked about it they told me that stuff got ate through within a year. The plastic coating just disintegrated. Are the cables in my links right?

With 12 pair, if one of the cables or a whole pair go bad I just have to reterminate both ends using a different pair and somehow mark the bad pair as bad. Seems pretty appealing when you think 5 years down the line.

 

[setishock]

Talk to the guys and gals at Supplier of Telecommunications Cable and Components. Including: Cat5e, Cat6, Ethernet, Coax, Cat3, Speaker Wire, Fiber Optics, Networking products, TP-LINK, Wireless routers, Switches, HDMI cables, Patch cables, Jacks, Patch panels, and much more.. It's where I get all my cable and network goodies. In the years I've been buying from them they demonstrated they know their stuff.

I suggest this > 191160 - Cat 6 Outdoor Direct Burial, 1000 Feet, 4 Pair UTP

As for grounding an aerial run in all the time I ran cables for camera and fire systems I never grounded the runs. Lightning is looking for a path to ground. If you don't provide it one the odds are low you'll take a strike. Besides public utility poles have their own grounding system.

 

[root]

there are a few simple do's and don'ts...

Do buy UV resistant cable, failure to do this will just mean that your insulation will perish.

Do buy cable that is meant to be hung between structures, I can pull cat 5 cable in two if I hold and end in each hand step in the middle and pull. conversely the cable that is ordinarily used for phones can support my entire weight! (I tried this when we accidentally downed the phone line going to our old house whilst felling a tree in the front yard!), if you buy regular cable it'll break as soon as any weight gets put onto it.

Don't use utility poles, -they aren't yours, even if the current ATT guy says it's fine what will the next say? what about if they come and replace the wooden pole with a concrete one? they won't re-instate your cables -(and will probably rip them off the poll in a way that means you have to re-do the whole run)

Do use your own structure to hang the cables from.

Do seek permission from the authorities, you say you're crossing some public land, will this cause a hazard in any way, you're hanging it lower than existing cables (and thus reducing the headroom for trucks etc) having a chat now will save you having to rip out and throw away what you did later.

Burying is a hassle, (especially in a public place), you need planning and permissions, survey for existing utilities etc, as you're going across a public space you'll also need to involve the authorities so that they can update their own plans etc to show that the cables exist! and you'll need the permission to close the lane whilst you're digging it up...

don't use runs greater that 100 meters.

Given all the hassles above, where possible use either direct laser links, or radio links with directional antenna, (gets around heaps of problems!)



And lastly, with respect to the first post.

if you connect
switch 1 port 2 -> switch 2 port 1
switch 2 port 2 -> switch 3 port 1
switch 3 port 2 -> switch 1 port 1

to make a triangle.

or similar, you're create a switching loop. which (unless you have managed switches that you've configured properly to understand this -with spanning tree) will cause all kinds of lovely broadcast storms on your network. packets that loop at layer 2 never die as there is no TTL in this layer.


grounding is a safety issue. in your regular cable there will likely be a pin connected to ground, (or a lower potential than lightening) anyway, so, the idea that by connecting the internal shield to ground you're somehow more likely to cause a lightning strike doesn't add up.
-the idea that this will help save equipment (at least give it a better chance) in the event of a lightning strike is likely true though.

Basically, if you can ground the equipment, then why wouldn't you?

 

[Captain Pooka]

Excellent posts! Thank you guys very much! And sorry I haven't gotten back in a while. I realize that my listing in numerical order below may sound attacking, I really don't mean it to. I just want future responders to be able to refer to each problem easily. Thanks again for the posts!

Firstly, Yes. Getting UV cable.

Second, you're right about the utility poles. I need to reevaluate. We may just end up burying the cable. If that's the case, I need something to bury it in, in which case I will call the people mentioned in the above post (thanks!). In the event I did call for permission, who would I call?

Third, I would never go above 100 meters, thanks though!

Fourth, I wish I could bridge... but they don't want to do that. They want cable.

Fifth, I would never create a loop. The configuration would be simple
Switch 1 to switch 2 (in building 2)
Switch 1 to switch 3 (in building 3)

Sixth, I know I need to ground it. I remember reading some guidelines where you are required to ground stuff (at least in Texas) that comes in doors. Catx was on the list.


Edit*

fourpair.com was actually not able to help me. The lady was really nice, but I asked her something along the lines of "I'm trying to network a few buildings and I'm trying to decide whether to bury cat6 cable, or run it along some utility poles. Do you have someone there who can help me regarding what I should buy in terms of conduit, cable, grounding, ect?"

That's paraphrased... but she said nope Oh well. If I did go with burial, they have direct burial Cat6 on their site.

http://hardforum.com/showthread.php?t=1726480

They recommend burying in plain old SCH40. They also make it sound like you should ground the cable ... even while running it in the ground?

Also... if I buried it, how will the end product look when bringing it in to the building? Run it up the wall and drill a hole high and run the cable?

 

[root]

If you're burying cable...

Generally speaking there are cable conduits suitable for burying, either steel armoured or plastic. These can be tacked to buildings using the appropriate clips, go into the building using the appropriate junction box.


Depending on what other cables you run with the data cables (power) you can get a yellow tape that you need to lay flat a few inches above the cable to warm that there is a cable immediately below.

If you have to cross municipal land then you need to talk the your local authorities.