Fiber Optic Cable Termination

Your terminal equipment is going to be designed for a particular connector style, which is what is going to dictate your connector requirements. Pick your transmitters/receivers before you think about terminations.

I learned how to terminate fiber just before the Y2K deadline. I worked for a company specializing in computer/network servicing and repair. The class we attended was put on by our cable supplier. Back then, doing fiber on a small scale meant you had to cut and polish by hand. Since then they have come out with some pretty nifty easy to learn and do termination tools. Any company selling fiber optic cable and equipment worth their salt should also carry the termination tools and be able to show you how to do it your self. The hand polishing kit used to run around $800.00 and the SC or ST connectors were about $2.00 each. When you complete the terminations take the time to test them so you know your cable is not part of any problem you have on startup. Fiber Optic test equipment can be a little pricey but you may be able to rent it.

Since you are not expecting to have to do this very often I would consider contracting the whole job out. If you get a professional to do a turnkey job you will have 4 working connections done right with certification paperwork.

Hi, I actually work in the fiberoptic communications industry and could possibly help you. When you say 100base and 10base fiber, I presume what you are saying is singlemode and multimode fibers. Multimode fiber will allow about 2km maximum distance communication with limited bandwidth. Singlemode fiber will allow up to 30km communications as standard but can go higher if required using certain lasers.

As for terminations, as said earlier, that will depend on the fiber optic modems being used/bought. Decide on the modems first then get the fiber cable terminated with the appropriate connector when purchasing the fiber. That way you will avoid bad/faulty terminations and a headache if trying to debug a faulty link. Industry standard is ST type where its a quick twist and release/lock of the fiber. SC has two types: straight (usually a blue connector) and angle polished (usually green coloured connector) The APC (angle polished connector) is for high end modems that require WDM (Wave Division Multiplexing) where there are multiple modems and critical bandwidths involved. LC on the other hand is a relatively new connector. Newer types of fiber optic modems now have optical devices that are removable and interchangable rather that a fixed type. This can be changed over with RJ-type connectors, LC, SC etc. I hope I haven't confused you more.

Have you chosen the appropriate modems yet? Again, I can help you further if required and you can send a private message if you require more detailed help with your project.

Thank you all for the responses. Since my original post, I have done some additional research, and am further along in the process...

The length of this first project is only 5,500 feet, but some of the next phases could push 8,000 or 10,000 feet. For reasons of platform consistency I am going with single-mode since I would need it on the longer runs anyway.

As a modem, Cisco makes a single-mode, non-managed modem with 1550nm wavelength and SC connectors.

I took the recommendation of just contracting out my connections very seriously. Although, I am a hands-on type of guy, I can also appreciate the headaches that hiring a contractor can eliminate. However, my company would like me to have the knowledge, experience, and tools to put things back together quickly if something gets dug up (and that happens surprisingly often in the railroad business).

Specifically for Ducky and others that have done this before, what do you think about the pre-polished connectors from Corning? It looks like I can get a high-end cleave tool as part of a kit from Corning for $1,600. Then, I can get a single-mode light source and analyzer from Fluke (FTK2000) for $2,700. That seems like a pretty cheap buy-in since I am comparing it to the $30,000 that two towers and some radios would cost me.

Just remember, if it gets dug up you will be replacing not repairing so make sure it gets burried deep enough or use the non-direct bury and put it in conduit. Though not much will stop a backhoe short of concrete duct bank.

Ya pays ya money and ya takes ya chances!

Actually, if damage due to digging up the cable is your primary concern, you should possibly be considering fusion splicing equipment for repairs...Putting connectors in the middle of a cable run to repair it is not such a good idea. More lossy than a fusion splice. Also, back in the days when I was in the fiber optic industry, most connectors relied on an index matching fluid for lower losses- and the fluids available back then had a tendency to degrade within about 4 years (we used to schedule sales calls for fusion splicers based on this little bit of "trivia!). Fusion splices (properly done) are forever. That was a few years ago, and I don't know how the industry has changed over the years...