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ZeroConcernstoday at 8:17 AM4 repliesview on HN

There's no link to the data sheet of the actual cable, but, yeah, looks like this should not have happened in such a short timeframe unless there's something really funny going on in that room, like ambient temperatures above 50 degC.

Another thing that should not have happened is installing the cable in loops in this way: any 'building' or 'underground' type cable needs to be of the exact length required at the demarcation point, fastened properly to prevent movement and terminated on a proper patch panel (can be a one-port box-type thingy for small setups), from where you use regular patch cords to connect your equipment.

(Loops are definitely allowed though, but that use case is mostly for aerial fiber to enable repair splices, and there are some very specific bend-radius and strain relief requirements, which, again should be spelled out in the cable data sheet)


Replies

Sesse__today at 10:49 AM

> any 'building' or 'underground' type cable needs to be of the exact length required at the demarcation point, fastened properly to prevent movement and terminated on a proper patch panel (can be a one-port box-type thingy for small setups)

How exact is exact? :-) I once had to reterminate some fiber that was cut and terminated to exact length, which means there was literally two centimeters from the wall to the connector. I literally had to squeeze the fiber splicer up against the wall to have a chance at splicing on new pigtails, but I had two mis-cuts and I was hosed. :-)

EvanAndersontoday at 9:35 AM

> Another thing that should not have happened is installing the cable in loops in this way: any 'building' or 'underground' type cable needs to be of the exact length required at the demarcation point...

This hasn't been my experience with fiber entrance cables terminated by ILECs, Spectrum, and Lumen. They typically leave a significant service loop bound to the cable ladder or backer board-- usually 15-20 feet.

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alienchowtoday at 8:42 AM

Thanks, I really appreciate the SMEs commenting here. I'm learning a lot.

Definitely learnt it the hard way this time. You're right that buried cables should be exact in length and fastened to a patch panel. I'll probably look into better conduit design as well for the next time (in 15 years?). Having shared conduits means I would risk damaging other cables if I tried to pull a new cable through.

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gertrundetoday at 8:32 AM

From one of the photos, the cable spec "G657A2" is visible on the outside - and specs listed for that indicate it's "bending insensitive single-mode fibre", apparently it can tolerate 10 loops around 15mm mandrel. (Which does surprise me).

But yes, agreed, a lot of "Er... why would you do it like that?" bits.

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