Installing preterminated fiber 5

[fs483]

Hello,

I've posted this question on a another site and only got a few answers. Maybe guys from here can help me also.

I have a project were fiber is needed to link up remote buildings to the main server room. This project is in the desert for mine exploration. Now in normal circumstances I would just call a company and have them run the fiber for me except this project is in North Africa hundreds of km away from any civilization. We need to use the local workers to dig the trenches, put the conduits and install the fiber. There's no way for us to send out a specialist out there and no there's no local companies that can do the work for political reasons. The ground is very dry, about 1.5% moisture. It does rain pretty hard sometimes only in the months of June, July and August but the ground dries very fast. I would like to install copper to link up the buildings because it's fairly hard to break copper CAT6 compared to Fiber but for all the obvious reasons (power spikes, grounding, lightning), I plan on using fiber. At least with copper I can terminate it myself. What kind of preterminated fiber (singlenode/multinode and what size and how many strands) should I be using. Should I use ones made for direct burial eventhough I will be putting them inside conduits ? I suppose OSP fiber is tougher than what's used inside. What kind of precautions for installing ? Let's say I need 50 meters of fiber. Can I order 100 meters of OSP preterminated fiber and coil up the extra on each end ? I seen fiber coiled up inside the protective cases but that's for inside use fiber, what about outside use ? Should I put sleeves to protect the fiber inside the conduit ? What kind connectors should have on the ends ? I will probably be using Cisco switches on either end. I heard you can get preterminated fiber with eyes on the end of easier pulling. I've also read the cable should be burried at least 40 inches below ground. What kind of testing equipment should I use for testing the fiber ? I just want to test it once it's installed and if they have connection problems further along, I would like the onsite guys to have some tools to help diagnose the problem. The cables will be running near blasting sites. Can the vibration damage the fiber ? I'll also be ordering Nema4 cabinets because of the dust/sand issues for the servers.

Do you have videos for installing preterminated fiber (pulling techniques, securing, coiling) ? I could send the guys these videos. Once everything is installed on site, then I will go and hook up everything.

Thanks

 

[dagwoodsystems]

I'm in the middle of securing a foreign government contract as well, and so I completely appreciate the troubles you face.

In my opinion, OSP is overkill if the pull is done inside conduit. My experience with fiber is that it's not much more sensitive than copper. If you are accustomed to treating copper in the recommended manner, then fiber should be a "no brainer". All the obvious rules apply: Don't pull, don't yank, have some guy feed while you pull. Use cable lube when necessary, and yes, you can run it down insulation-packed drywall totally raw...just like copper.

The first key to pulling fiber is a simple and easy path. Use "sweeps" (gentle PVC curves), not elbows when changing paths. Having a partner to feed makes all the difference in the world.

It is also absolutely critical that you pull with the Kevlar, not the fiber jacket itself. If that's new information to you, then visit Leviton's website. They have some killer training videos on this topic.

Preterminated fiber makes sense. It's factory tested and you don't have to worry about termination tools or the associated training to get that piece done. However, you need to emphasize the need to keep the fiber covers in place while pulling. Dirty fiber terminations kill data. "Dust Off" and other compressed gas products will clean the laser or LED transcievers on the Cisco boxes. But care and special cleaning papers may be the only way to fix a dirty fiber termination.

I could go on and on and on about all the things you might run into. I think the best way for you to approach this task is to bury yourself in some fiber training. It won't take long before you'll see the real obstacles ahead of you.

Tim Alberstein

http://www.dagwoodsystems.com

 

[oldtimerbob]

You can get the preterminated fiber that comes with a 'pulling' sock that will make your life a lot easier.
If in doubt use the indoor/outdoor type of at least six strands.
It comes already tested but you may want to use a light scope to check for any broken strands before and after you install.
Good Luck,
Bob

Has been in the cabling business for about twenty years and is now the Sr PM for a cabling company located in the Los Angeles area.

http://www.globusinc.net

Also a General Class Amatuer Radio Operator.

 

[buitenhek]

50 meters of fiber in conduit installed by non-qualified installers===talk about real world situation!!Wow

1. Copper with surge suppressors, to minimize lightning strikes and electrical float. But--
2. Fiber is the better (no electrical problems). With OSP you also need a breakout kit each end. If you decide not to use OSP, use PVC and not plenum rated. Plenum will break down faster in water than PVC.
3. Preterminated min 6 strand multimode fiber with pulling sock.
4. Install the largest conduit that you can afford but keep in mind EIA/TIA standards for cable/conduit install that max 40% fill applies. Limit bends. Each 90 degree bend reduces conduit capacity 15% and increases jam ratio. Standard says limit of 2 - 90 degree bend between pull boxes
5. Instruct people pulling the fiber about smooth-steady pulls and ask manufacturer about max pull strength. Review that with pullers and demonstrate that with a large fish scale.

Regards
Peter Buitenhek
ProfitDeveloper.com

 

[mikeydidit]

I agree with Tim that this doesn't have to be a direct buried type cable. I use a lot of indoor/outdoor rated fiber and I have no problems with it. It is a lot smaller in diameter and a lot lighter, so that will make it easier to pull in.

I don't know what type of help you have there to pull this in, but you really need to stress to them to not get ugly with the fiber pulling it in. While the fiber is strong, it won't take much to break those connectors and then you have something that is useless. The pulling harness or fingers work very well and keep your connectors covered during the pull in process.

You may want to also install a couple of pull points to help take some of the weight off the cable. The pull boxes or hand holds are cheap and will let you use your conduits for something else should something else come up. You may want to look into install several conduits and have a spare for the future with pull points already installed. Thats how I do ours anyways. The conduit is cheap compared to the labor to install them.

Hell, there are no rules here - we're trying to accomplish something.
Thomas A. Edison

For the best response to a question, read faq690-6594

 

[fs483]

Should I use singlenode, multinode and what size ?

 

[mikeydidit]

I would run a single mode. Most all the switches now have LX G-Bits and they will work for MM or SM fiber.

As for how many thats really your call. I usually don't run less than 12 for expansion. The next thing you know they will need you to connect anther building and this will give you spare fibers to use. They fiber is not that expensive it is the cost of getting it in the ground and pulling in another that will cost you.

Hell, there are no rules here - we're trying to accomplish something.
Thomas A. Edison

For the best response to a question, read faq690-6594

 

[brianinms]

If you are only going 100 meters I would use multi mode as the gbics for the switches are cheaper.

 

[fs483]

I will confirm with the engineering plans for the exact lenghts. With multi-mode, do I pick 50 microns or 62.5 microns ? What about the type of connectors on the ends or it really depends on my Gbics ?

 

[mikeydidit]

The ends do not really matter as you can buy any configuration you want to. Most people are still using the SC connectors. Most G-bics are either SC or the newer LC. If you go ahead and use the MM use the 50 micron. It has a better overhead than the 62.5 does which means more speed over a greater distance for you.

Hell, there are no rules here - we're trying to accomplish something.
Thomas A. Edison

For the best response to a question, read faq690-6594

 

[robertjo24]

One item of note,
You can order the fiber with an interconnect plug installed that would plug into a preterminated pigtail/distribution box. This will make it significantly easier to pull.
I know Corning has this, (

http://www.corningcablesystems.com,

"Plug & Play Systems")and I have to assume others do as well.
As a side note, you can get field installable connectors that are simple to install. Corning makes a Uni_Cam connector that is very easy to install, and you can rent teh installation tool kit that comes with instructions. It takes all of 90 min to learn if you have never done it before.

 

[fs483]

I looked over the plans and some of the fiber is going to be at least 150 meters. I also plan on running copper between adjacent buildings to I'll be putting in lightning protectors on both ends. My supplier is able to get CAT6 protectors, just waiting on the price (

http://www.itwlinx.com/home/default.asp).

My supplier is also quoting on only 2 strands of preterminated fiber that will be inside the protective orange conduit. That way, when the guys pull the fiber, they will actually be pulling on the conduit. This orange conduit will be placed inside a 4 inch PVC rigid conduit. Supplier also said to avoid bends greater than 20 degrees. He can put any type of connectors I want. They also have armored fiber but those require onsite termination and a fanning kit. In the remote building, I'm trying to see if it's better if I put GBICs inside my switches or use media converters. Same thing on in the server room. I think media converters will cost less and I can ship them a few extra ones so they can keep as spare. Any comments on TrendNet Media converters ?

 

[fs483]

From what I can see, if it's below a few miles, MM fiber will be fine. Now, the switches or converters that I will get will handle 1GB fiber to copper, will I be able to achieve 10GB with this MM fiber (if I were to put in better gbics/converters) ?

 

[robertjo24]

Typically, MM fiber is rated up to 2KM.
The GBICs/converters will determine the actual distance.
From what I have seen, gigabit rates are not available for over 300 meters. You should look, but I don't think you can find gigabit rates for MM out to 2KM. I think 100 MBit is the limit there.

 

[brianinms]

I would seriously recommend having at least 3 pairs of MM and 3 pairs of SM. You never know when you will need more fiber.

 

[Jtodd]

When deciding on what fiber to use, what are your network speeds? If you're even close to going over 1G on your fiber link, you'd have to look at Laser Optimized 50 micron. But low end LO 50 is limited to 300m for 10G (obviously longer for 1G). But LO 50 glass is more expensive than single mode glass, and the difference in electronics (at least at 1G) are not that great anymore between SM/MM. SO, I would suggest singlemode (cause then you'd never have to replace it regardless of what your speeds are). I would also suggest outdoor rated cable, even though it's in conduit and innerduct. We started using indoor/outdoor and I'm not really happy with it's supportablitly in a vault. As for connectors, preterminated would work. Look at the MPO or MTP connector. Most connectivity vendors have them. It's a 12 or 24 strand single connector, that plugs into a cassette that breaks out to the individual connectors. And those connectors can be any flavor you want.

Here is a link to Corning's flavor of such animal, should get you started...

http://www.corningcablesystems.com/web/library/litindex.nsf/$ALL/LAN-731-EN/$file/LAN-731-EN.pdf

Justin T. Clausen
Physical Layer Implementation
California State University, Monterey Bay

 

[Jtodd]

Ooops, forgot...I wouldn't put anything less that 12 strands, maybe even 24.

Justin T. Clausen
Physical Layer Implementation
California State University, Monterey Bay