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Fiber - how 1

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ssphoenix

IS-IT--Management
Jan 22, 2001
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Hi there,

I am in need to wire a remote location from the main building of a hotel. The distance between is approximately 3/4 to 1 mile.

Fiber is my first choice but not sure the shielding process. I am in AZ.

Thanks
 
Unless I misunderstand you, the only "shielding" you need is to keep the elements out of the fiber. Where is the fiber being run, though conduit, underground, on poles, etc?
James P. Cottingham
 
I will have to run it in the ground. However, I am not sure if I should take extra precaution for being in Arizona. It gets very hot. How far in the ground I have to lay the fiber? I would like to use conduit. Any shielding within conduit?

Thanks

 
Normally you run plastic conduit and then insert a smaller flex guide for the fiber run. This keeps the strands from different runs getting wrapped around themselves. I doubt you need that part of it. Unless you are in the Northern part of AZ like Flagstaff and such where it does freeze, I would imagine a foot or two is plenty as long as you mark it so not to shovel through it at a later time.

The fiber itself does not require "shielding" as it does protection from being crushed or bent beyond the bend radius. I have used fiber that you could bend over and smack it with a hammer and not break the fiber. Expensive pretty damn tough stuff. Put a fiber patch panel at each end to keep from having to mess with the primary fiber run. I like SC or ST connectors and 3M has crimplocks that do not require the bad old days of expoxy. Always give yourself a service loop of fiber at each end.. just in case. and ALWAYS pull at the mim 4 strands.. two for now and two for later if needed. The cost of the fiber is cheap compared to having to pay someone to pull in another pair at the last minute when the first pair breaks :(

It is possible to get jacketed fiber.. multistrand with the tough black plastic jacket.. it's a pain but very durable.

Mike S
"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin
 
Even in a PVc pipe, use outdoor grade fiber. It has the tougher jacket mentioned but also is filled with a sealing "goo". It's an ultra pain to work with but it lasts. That's why it's called "outdoor" grade.

Check with your local city/county gov't and maybe local utilities. I'm sure there are some local codes that govern how deep something needs to be buried, even a private run like you're proposing. If it's not regulated they should at least be able to give you recommendations on how deep to bury the run for your climate.
Jeff
masterracker@hotmail.com

If everything seems to be going well: you don't have enough information.......
 
MasterRacker is correct, local authorities will probably have a say about how deep things should be. They may also be able to tell you what kind of conduit to run, too.
James P. Cottingham
 
If the cost of conduit is too high I would recommend a wireless solution. Black Box makes a good product. 11MB Connetcion. Maybe this can help.

Tracer
 
I would take caution with one of the recommendations above. Since you are trying to go 3/4 - 1 mile away, you will be using Single-Mode fiber as opposed to Multi-Mode fiber. The difference in termination is significant, and for an investment of this order, I would run away from any installer who will not terminate your ends by hand. The "crimp on" variety, if they are even available for single-mode fiber, are slightly more lossy than a properly polished hand termination. With that kind of investment you shouldn't have to worry about termination loss. Multi-mode fiber is more forgiving in that regard. Single-mode fiber is not.

As for the number of strands, you will be hard-pressed to find a cable of 4 strands or less. 6, 12, or 24 are more common.

Definitely go with the local building codes for cable burial. You should be able to use outdoor service plan/armored cable to avoid the use of conduit.

Terminate the connections with SC connectors over ST connectors. It will save you headaches as the SC connectors are more common in devices that use fiber (e.g., Gig-E switches and fibre channel devices). If you use an ST connector to the patch panel, you will need to use an additional adapter/cable to connect to these devices. Every additional adapter adds some loss. It's more reliable at any rate because your IT guys are less likely to manhandle the SC connection and scratch the polished end.

Finally, make sure the installer gives you a copy of the acceptance/loss tests before you sign off on the job. They should test each strand a minimum of three times.
 
Check Cisco point to point wireless, the cost of fibre for 1.5 miles remember you have right of way fees, installation costs, they recomment 48 inches minimum burial distance, and the route must be marked. You can buy cable, get a contractor to plow the cable in, then have the ends terminated. Wireless should be a lot cheaper.
 
ssphoenix, Since wireless has been mentioned, I'll go head and toss in my couple o' pennies as well. Wireless will NOT give you the bandwidth that fiber will, but I'm sure you know that already. The advantages for wireless today are money, install time, and money. Did I mention money? It will be cheaper, but there are consquences.

Fiber is more reliable, since it will not be interfered with by those lovely Monsoon electrical storms you get out there in the desert. You will probably have signal degradation and maybe out-right out-of-service conditions with wireless during those nasty storms. If the remote building is a critical site, don't mess with the wireless stuff.

Fiber burial...Something to watch for down there in AZ is wash out. Make sure you can do your fiber run in an area that does not flood or you'll see that nice 48"depth get washed away and your conduit/outdoor fiber will be sitting on top of the ground.

Good Luck and happy cabling.

P.S. If anyone knows of a wireless solution that doesn't get interference from ye old mother nature, pass that info on. Monkeylizard
-Isaiah 35-
 
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