Bend radius for normal SMF...

I suspect I'm good, from what I can find, but I'm not finding exactly what I'd like to find, so I'm going to ask here and see if anyone still reads the group while I'm at it...

I bought an ADC/Tyco Electronics MST-12MH00-A1500A fiber drop mostly for the cable, from ebay, since I couldn't find any more reasonable cost source for drop fiber. It's (from what I recall when researching before buying it) normal single-mode fibers in a loose tube, with the fiberglass rods on either side that make it drop cable and delightfully robust. Certainly will be harder to kink than normal cable.

It's an ADC/Tyco product, but uses Corning flat drop cable (made in

2012.) All the current Corning flat drop cable documents I can find are for their newer bend-insensitive products, and don't actually admit to a bend radius anyway. The ADC/TE documentation is also not mentioning a bend radius, or much about the cable at all, really.

SFM28e+ claims to be good out to 1625 wrapped on a 60mm (diameter) mandrel (bare fiber)

Commscope flat drop claims to be good with an installed (radius) of 3.2 inches/8.1cm. Not the brand I have, but the same type of cable, with a useful data sheet I can actually find.

I need to either put the cable in a 2" weatherhead with an effective radius of about 3.5 inches/8.5cm, or come up with some cockamamie scheme to give it a larger radius. This would only be installed radius - the weatherhead top pops off for pulling. The cable, tested at an end, physically does this fine. Given the mandrel-radius for the bare fiber test, I have to suspect that this will be fine - it's loose tube cable, the fibers will not be pinched.

Anyone with practical experience? I know it will be less affected at

1310 where most of my stuff runs, but one piece may be used at longer wavelengths, and I'd like to sanity-check before I install it.
Reply to
Loading thread data ...


I remember reading that the standard smf 28 bare fiber has a bend radius of ~16mm and at this bend the fiber has a life of over 10years. Any jacketed fiber must have a bend radius greater than this.

Of course there is also a minimum loss associated with bending but I don't suppose you have to really worry about that.

Hope this helps.


Reply to
Sumeet Yamdagni Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.