fiber optic cable life expectancy

[cvirgil]

Anyone know the typical life expectancy of fiber optic cable installed underground in conduit? What are the factors affecting the life expectancy?

Thanks.

 

[itsmoked]

googling "life expectancy of fiber optic cable"
Gets 190K returns like:

http://www.fiberoptictechnology.net...SSUE=0403&RELTYPE=PR&PRODCODE=0000&PRODLETT=C

http://www.fiberoptictechnology.net...SSUE=0402&RELTYPE=PR&PRODCODE=0000&PRODLETT=B

http://www.ct-magazine.com/archives/ct/0199/ct0199g.htm

It looks like a hard number to pin down... I see 15years to 40!

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

 

[IRstuff]

That's not necessarily surprising.

First, fiber-optic cabling in large quantities and lengths have only been around for only 20-odd yrs in mass applications.

Second, FO cable, if properly laid and protected, should have no failure mechanisms, other than spontaneous devitrification.

FO cable is obviously sensitive to bending, but also, must be protected from moisture intrusion, thermal and mechanical stresses that might weaken the material or its protection.

TTFN

 

[MikeHalloran]

Backhoe intrusion should be counted as a failure mode. If no metal was buried with the FO, it's inevitable.

Failure to remember the location of the (ends of the) spares you buried may not be strictly a failure mode, but it happens.





Mike Halloran
Pembroke Pines, FL, USA

 

[ScottyUK]

This is a cross-post from thread735-148917.

Don't start multiple threads on one topic - it fragments discussion.


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I don't suffer from insanity. I enjoy it...

 

[itsmoked]

Actually I believe since glass is actually liquid with a very LARGE viscosity, that the graded cores will diffuse and change over time... Not sure how long though.

Also as mentioned water will toast it. So it probably comes down to the jacket and splice qualities.

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

 

[ScottyUK]

A thought - for discussion:

Termination methods and splicing: do these elements degrade more quickly than the fibre? I guess a fusion splice shouldn't, being the same material as the fibre, but what about the others, like bonded splices?


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I don't suffer from insanity. I enjoy it...

 

[VEBill]

"...glass...liquid...very LARGE viscosity....diffuse and change over time... Not sure how long though."

> Age of Universe.

This urban ledgend (glass viscous liquid that changes) apparently comes from ancient windows that had glass that appeared to be drooping. Investigation reportedly revealed that the glass was pre-drooped when it was made. Further investigation showed that any flow of glass would require billions of years.

(All this according to what I saw on some science show on TV that was addressing this very topic.)

 

[itsmoked]

Hope it wasn't MythBusters...

ScottyUK; Typical..I make bonded splice curing ovens but have no clue as to the bonded lifetimes... Like the car mechanic with two dead cars in front.

I can only surmise that the bonding life time would be shorter than the fiber but longer than any expected obsolescence. Look at the million 30 year old sailboats bobbing about. Water does pass thru slowly. Yes, yes, VE1BLL verrrry slowly but a little water in a fiber system is a bad thing.

The life expectancies are probably very dependent on the cable route. I.E. swamps, overhead, dry, etc. Be a while before the truth emerges.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com