They twist the buffer tubes around each other in a loose tube cable. It's so when you make a coil you're not putting all the stress on the fibers on the outside of the coil, but rather it's spread evenly.
Sent from my iPhone > On Apr 7, 2017, at 6:06 PM, Justin Wilson <[email protected]> wrote: > > The line guys would do the following at the local phone company I worked out > many many years ago. I am sure there are lots of better ways to do it with > modern processes. > > The cared about a few things. Where can I find the splice points? Where can > I find vaults? Where are my slack points on the path and how much is left or > do I have? How do I do all this in the middle of the night during the rain? > During install it was specified where the slack loops happen. They would > care about the overall material used when running cable. If they ran down a > road to a vault all they cared about was how much length off the spool was > used. This was documented. > > Once everything was installed the certification notes were included in the > construction closeout drawings and put in an appendix at the back of the > book. The linemen did not care about such things. > > I typical do not see fiber being in a twisted pair type of configuration. > Not sure what everyone else uses, but all the ones I pull apart are side by > side. I think there is even a “how it’s made” on fiber optic cable and it > has a machine that makes sure they do not get twisted. > > Just my .02. > > > Justin Wilson > [email protected] > > --- > http://www.mtin.net Owner/CEO > xISP Solutions- Consulting – Data Centers - Bandwidth > > http://www.midwest-ix.com COO/Chairman > Internet Exchange - Peering - Distributed Fabric > >> On Apr 7, 2017, at 4:23 PM, Adam Moffett <[email protected]> wrote: >> >> I started a spreadsheet to document a fiber line. I figure I'll make a new >> file for each cable, a worksheet for notes on the cable as a whole, a >> worksheet for each buffer tube, and a color coded column for each fiber. >> Each row will be 100'. My thought was, if I have a splice enclosure 4200' >> down the line, I'll go down to row 42 and enter "Splice enclosure on pole >> 305". Then I can note on each fiber whether it passes through the >> enclosure, or note what it splices to, including a reference to another file >> if necessary. >> >> I understand they used to do something similar with 3-ring binders for >> mapping the pairs on phone lines. >> >> The first question I ran into was which distance do I go by: >> The actual distance the line has traveled >> The cable length, which will be ~15-20% longer due to slack loops >> The fiber length, which will be longer still due to the built in >> twist.....but is easily measurable with an OTDR. >> All three somehow? >> >> Is this even a smart method? Plan B is to use GIS. I can add every pole, >> cable, and enclosure as objects in their actual location with properties >> describing the actual distance, cable length, fiber length and anything else >> I want. >> >> That would be technically better, but I'm the only one here who can use the >> GIS software whereas any boob can type into a spreadsheet. If I use a >> Google sheet then multiple people can use the same sheets and fill them in >> from their phone. >> >> I'm sure these problems have been solved before, so what do you all do? >
