Fiber and conduit

[Drewy]

In the next few months I'll be moving home. Currently I have a number of servers in a rack (along with switches and ups) in my garage. The garage is actually attached to the side of the house. I have 4x1gb cat6 cables running a bridge back to a switch in the house.

New property has a detached garage. I also want a better (easier on the eye) solution than bundles of cat6 cables running down the side of the house etc.

One of the switches in the rack is a lb6m, so I was thinking "why not run a fiber" (or 2) from the house to the garage. Due to the layout of the property and wanting to run any cable\fiber in the least visible way I'd probably encase either in 20-35mm plastic conduit. Probably also drill through the house external wall and fit a length of conduit through the hole and cavity (UK, so brick houses with cavity walls). The would make teasing the cable\fiber through the exit hole easier than trying to poke it through naked.
Total cable run is going to be less than 100m.

So to my question. Can I expect to pull a fiber (something like om3 duplex with LC connectors in place) very carefully through the conduit without damaging the fiber? Obviously I've got to be mindful of bend radius's.
Or am I better forgetting about the conduit, biting the bullet and purchasing some armoured fiber such as 4core 50/125 OM3 SWA Pre Terminated Fibre Cable . I'm assuming 4 core fiber equates to 2 x duplex pairs or can be used as.

Thanks

 

[PigLover]

Fiber in conduit is fine. Your biggest problem will be pulling it with connectors attached. You'll need to run bigger conduit than you need just for the fiber. I've pulled with LC connectors in 3/4 inch conduit, though you'd probably better off with 1".

Pull more than you need. If you think you need 1 pair, pull 2. Its a PITA to pull more later without damaging whats already there.

It gets easier if you are capable of terminating the ends yourself and can just pull the raw fiber, of course.

 

[cesmith9999]

100m is a long distance. I would have a professional do that pull for you. yes, you could do it if you were patient.

I would recommend burying the conduit as well. accidental shovel accident at that distance would be painful. Plus you could pull more fiber later if you wanted to.

and I agree with @PigLover

Chris

 

[Drewy]

Thanks for the replies.

I'd for sure be purchasing ready terminated fibers. I'd also fit inspection boxes along the conduit run, so wouldn't have to pull the full 100m in one go.

I decided to pull 2 pairs rather than the 1 I actually need. 20gb is way more bandwidth than I need. Even if 1 pair dies I'm still good.

So you both think pulling pre terminated fiber through conduit is doable, right? No need to go the armored route?

Neither the conduit or armored would be buried, they would be saddled around a perimeter fence.

 

[Pete L.]

As mentioned 100 Meters is a long run but if you have several access areas it is certainly doable. I would absolutely run more than one connection at the same time just for a backup or even load balancing / backup. You could do a "Trunk Cable" which would give you several conductors in a single cable. Fiber Store is a great place for items like that.

MTP/MPO Trunk Cables Manufacturer & Supplier | FS.COM

These would require a breakout Panel on each end and might be more than you are looking for but an option.

Even though you are running in conduit I would still suggest armored cable just because it is less likely to be damaged when running them and if you ever do want / need to pull them out again you can do it again with less likelihood of damaging them. Unfortunately the fiber I've dealt with isn't very "Slippery" and tend to be a little abrasive when rubbing together which is another good reason to run more than you really want / need so you don't have to do it again.

 

[Jon Massey]

I did the same as you a few years back - patch panel and switch in small rack in the attic (aka the l0phtrack ) with 20mm conduit down the side of the house, across the shed and into the garage. To avoid drag and wear I pulled in sections - i.e. pull the whole run through the straight down the side of the house, fit the elbow, pull the next straight, fit elbow etc. Quite a bit more laborious but worth it. As I'm a cheapskate, I just bought four 50m LC-LC OM2 patchleads and wrapped the ends (with the bungs in) in a bit of electrical tape for protection, with the connectors staggered to keep the width down. The "proper" multicore preterms with tougher jackets and pulling socks are a more rugged solution and are what I use when work's paying, but you'll struggle to get the ends through 25mm conduit let alone 20mm. Unless they're going to be at risk of mechanical damage (i.e. if they're running round the edge of the building/strung over catenary) then just running outdoor loose tube on its own would be fine and cheaper than SWA/CST armoured.

edit: I see that the preterms from FS ( 50M Multimode 8 Fibers LC/FC/SC/ST Pre-terminated Pulling Eye Fiber Optic Patch Cable | FS.COM ) have a bit of cable braid heatshrunk on rather than the 25mm pvc pipe used on the preterms we get from turnkey fibre. You might have more luck pulling a preterm with that sort of pulling sock through conduit! Shipping on that item is a bit of a shocker, mind.

 

[Drewy]

Thanks all.
Any particular advice for attaching the pull cord (or tape etc) to the fiber leads? I'm thinking something to attempt to spread the load\force over a section of the fiber rather than just tying onto one point.

 

[Jon Massey]

If you're buying ones with the pulling sock/eye then that'll be how you attach your pull string. If you're going the hacky cheapskate approach, then I layed about 6" of the end of the string alongside the end of the leads, wrapped about 2-3" in tape, then looped the string back and taped round the whole shebang.

 

[bds1904]

Pulling "patch cords" through 20m-30m of smooth wall conduit is easy without lube.

Pulling "patch cords" through smurf tube (corrugated plastic innderduct) that's 10m-20m is easy without lube.

If you plan on using cable lube add 10m the distance estimates.

The "right way" to do the project (aka expensive but durable) would be to use a pre-terminated fiber cable assembly rated for use in outdoor conduit that comes with pulling eyes. Run a lube sock through the conduit one way then tie the lube sock on before the fiber cable (pulling the lube sock and fiber) and pull away. You'll be able to pull the entire distance alone, by hand with that method.

http://www.lanshack.com/4-Strand-Cu...-10-GiG-IndoorOutdoor-Assembly-P1982C236.aspx

I've used them on several projects with great success. Very easy to pull, even over distances of 300m.

If you are buying the house and plan on living there for 10+ years I say do it right. Run a continuous conduit from one building to the other and use a cable designed for the job at hand.

If you aren't going to bury the fiber you will absolutely have to use UV rated outdoor aerial fiber. Nothing else will last more than 3-6 months before the jacketing and buffer tube become brittle.