how do you terminate fiber optic cables and test them

[jonesjax]

I have a job wher we are pulling in a multimode fiber cable into an existing conduit. Dia. is 900 micros / 5 mil/ .200 it is to have eight ST terminations four each end. Must be epoxy & polish. Provide eight ST terminations four each end.

1) how do you do the polishing is it like using a dremel tool what is the epoxy for

2) how and what do you need to test the cable, i thought maybe a good pen light might do then send morse code and decifer. ha haha

thanks

 

[dereckbc]

jonesjax, don't take this wrong, but get someone else who is trained and has the equipment to do this. For example a the test equipment to check the splices and connections is called a OTDR (Optical Time Domain Refelection) analyzer, about $40K worth, and requires extensive knowledge/training/experience on how to use it.

Terminating optic cable also takes some very special equipment, training, and experience. No rookie will ever get it right.

Sorry to be negative, but you are in way over your head.

 

[petersonra]

I concur. Don't get burned by what looks like something simple, especially the testing side of it.

You just might be able to get pre-made cables though.

 

[tallgirl]

Do you know the cable lengths in advance? If so, you might be able to get them manufactured. But even then, if you've never worked with glass, get someone else to do the work and learn from them. Glass isn't like wire -- it cares a lot about how it's treated.

I did like your "light pen" idea -- I look at the ends of fibers to see if I've got a transmitter or receiver cable in my hands. Easier than looking at copper and wondering which end is up!

 

[hbiss]

I look at the ends of fibers to see if I've got a transmitter or receiver cable in my hands.

One of the first safety precautions you learn is that looking into a connector is something you should never do if you value your eyesight.

-Hal

 

[tallgirl]

I look at the ends of fibers to see if I've got a transmitter or receiver cable in my hands.

One of the first safety precautions you learn is that looking into a connector is something you should never do if you value your eyesight.

-Hal

These are LED-powered cables, not lasers.

The laser ones have warning signs that say "Do not look into the laser with your other good eye."

 

[MAK]

Good luck

Good luck

You use special strippers to remove the jacket & expose the core. The epoxy is used to fasten the ST connector on to the end of the bare fiber. I use a hot melt kit where the connectors are pre-impregnated with the resin, you heatup the connector with an open top oven. When it's hot enough you stick the fiber in the connector. You want the core of the fiber to stick out through the impossibly small hole on the face of the connector.Then comes the scoring of the fiber, nik the fiber on one side as close to the connector face as possible. Then you polish the face of the connector with special paper. This only one way to do it there are a ton of ways to do it. You need very expensive equipement and serious training. Do not attempt it with out training!!!

 

[don_resqcapt19]

The pre-polished connectors work great for installations that are not going to be moved around a lot....strip, clean, cleave, crimp and test.
Don

 

[hbiss]

Kinda of like looking into the barrel of an unloaded gun and pulling the trigger, looking into a connector isn't something that you want to get into the habit of doing.

-Hal

 

[MAK]

The pre-polished connectors work great for installations that are not going to be moved around a lot....strip, clean, cleave, crimp and test.
Don

I talked to a guy the other day about the pre-polished connectors & he said they were awful (filled up with water?). I would prefer to use something other than the hotmelt kit, but not sure if purchasing a crimping kit is going to be a wise choice. Any suggestions on the crimp connectors, where to use & not use? Thanx

 

[Tourcosta]

Fiber Termination

Fiber Termination

SMP (Superior Modular Products) has "toolless" fiber connectors for both SC and ST that are extemely easy to use and do not require a termination kit per se. All you need is a cleaver which can be acquired through most electrical supply houses. By downloading the video from the SMP website you can successfully terminate fiber in minutes. I used Amp Crimplite for the last 5 years but found these to be much easier and the success rate is much higher. They are a little pricely (I think I paid around $12 each the ones I just bought) but work well.

 

[RayS]

SMP (Superior Modular Products) has "toolless" fiber connectors for both SC and ST that are extemely easy to use and do not require a termination kit per se.

I haven't used them- and I think there were some listed as reuseable. I am curious-

After the cleave, there is still polishing, right?
How is the loss?

I was getting about .3 DB with the epoxy kits, but did not do a lot of them

 

[Tourcosta]

SMP Connectors

SMP Connectors

I was told that the ST connectors can be re-terminated (I don't know why or why SC cannot) but I never tried. There is no polishing after the cleave. You just stick the fiber into the connector and press the cam mechanism and you are done. I don't remember the loss because we were using a two tester with fiber modules and I just worried about the pass and haven't looked at the detail yet. I did about 30 of them with up to 1500 feet of fiber and had no problem. Also, I said in earlier post that you only need a cleaver but I guess you need strippers to.

 

[don_resqcapt19]

Mak,

I talked to a guy the other day about the pre-polished connectors & he said they were awful (filled up with water?).

How did they get filled with water? They do have an "index matching gel in them. I have not had any trouble with them, but all of them that I have done are installed in protective enclosures of some type. Most have been in indoor locations, but I have had some in outside applications. I use the Corning Unicam products on 125/62.5 multimode fiber. The typical insertion loss is 0.3dB or less. I have found that it is often in the 0.1 to 0.15 dB range. They are easy to work with and if you have some mechanical dexterity and can read and understand written directions, that you can install them with little trouble. There are details that you need to know about the fiber installation like the fact that you can’t put fiber in conduit using standard size LBs as the bending radius would be too tight. There are also different types of cable construction for inside and outside (low temperatures) and you have to limit the pulling force.
The first fiber I ran (about 15 years ago) was a plant wide distribution system using the existing power and phone underground duct banks. That fiber was 12 or 24 fiber cable and the inner “strength member” was a fiberglass rod about 5/16” in diameter and was one of the best “fish tapes” I have ever used. We could push the fiber 300-400 feet in the ducts. Newer fiber has a much smaller “strength member” and normally has to be pulled. The older fiber also had a water blocking gel much like underground phone cable that had to be cleaned off before you could terminate the fibers. It often took 2 to 3 times longer to clean the gel off than it did to make the actual termination. The newer fiber uses a dry water blocking technology and is much easier to work with.
Don