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Comment by maples37 | Hacker News Reader

Since fiber is non-conductive, I've heard that it's code-compliant to run optical fiber in the same conduit as your power lines. (Normally, high-voltage and low-voltage conductors are required to be in separate conduits even if going to the same place.)

Of course, this requires that you ran your electrical in conduit instead of direct-bury, so this might or might not work for you.

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I did exactly this when I built my shed (with the same justification) - running fiber in the same conduit as the power to the shed.

But, I found out during inspection that the Canadian Electrical Code prohibits this, unless the fiber is functionally related to the power lines it is running with (section 56-200).

The explanation I received for the rule, was that someone like a telco installer could try and follow the fiber line, and find themselves in a dangerous situation (inside an electrical panel they aren't trained to handle).

I was able to get an exception since I am the only one who will ever open the cabinets/work on this fiber, since it was not the main internet feed to the house, but just to an outbuilding.

You still have to consider conduit fill ratios (though fiber usually does not take up much room). But more importantly, you have to make sure the conduit terminates on both ends in some way that makes it easy for you to separate out the fiber and power wires accordingly. If the conduit goes from electrical panel to electrical panel it really wouldn't be ideal to pull the fiber through.

Running anything other than mains power in the same conduit as mains power is a bad idea, there are many codes and many “spirits” of the code that prohibit this. PVC is insanely cheap, a separate (properly spaced!) conduit for telecom is the way, and is future proof.

Also, it can be ran through water pipes to retrofit areas that you dont want to dig up [0]

[0]: https://www.bbc.co.uk/news/articles/clygd9nznj9o

Also, it can be ran through water pipes to retrofit areas that you dont want to dig up

And if you're really ambitious, you can run it through oil pipelines.

One of the first nationwide VOD networks was a private one run by a big oil pipeline company in Houston. I knew someone who worked on one of its daily live news shows that was transmitted that way to energy traders and oil/gas executives in offices across North America.

They made a mint selling the excess bandwidth to television stations and networks.

There's no way the fiber was run "through" the pipeline. They likely just used their right-of-way to run the fiber next to, attached to, or dug underneath, the pipeline.

I hope you don't mind if I believe the word of people who were actually involved with this over some rando on the internet second-guessing them 30 years later.

Pipelines are already filled with all kinds of electronics.

https://www.slb.com/products-and-services/innovating-in-oil-...

An oil filled anything has always been the gold standard to run wiring through. It’s insulted, temperature regulated, vibration resistant etc etc. also a huge pain if something does break … lol which fortunately is unlikely !

Sadly, the electrical was direct bury. I was hoping for conduit because I've had really good luck with prefab fiber assemblies in just this kind of application. No such luck here.

fs.com will custom build direct bury OS2 assemblies for reasonable prices. I'm a happy customer thrice over.

https://www.fs.com/products/70220.html?now_cid=1148

Depending on your lengths, budget, and your region's weather, might be worth giving second thought to just renting a little trencher and running a spare conduit or two (and maybe a water line too) then you're not locked in with one technology, and if that direct burial fails you can pull a new one in no time.

I enjoy getting dirty though, so I had fun hand trenching out to my shed -- didn't run water and I'm kicking myself

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