Fiber Optic with power cable in raceway question.

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Flyinbryan

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Here is a unique situation I have I need help with. I have a fiber cable that is armor with a PE jacket for outdoor use. This cable does not carry a FOC or a FON rating due to it being for outdoor use. It was originally intended to be direct buried. The client decided to put it in a ductbank instead due to direct burial requirement in the specs being too deep. I created a 6" sleeve in concrete and I have put this armor fiber cable in the same conduit with a 600V power cable that is also armor and carrying a 110VAC circuit. Both are for CCTV camera use around the perimeter of a PE plant. They are saying I am in violation of NEC 770.133. However, this only pertains to indoor use rated cable that is always marked FOC or FON. The manufacturer of this fiber optic cable is saying the power circuit (110vac) can induce a voltage through the 600V jacket, through the armor around the power cable jacket , then through the PE jacket around the fiber cable into the armor of the fiber cable and create a safety issue. Do I have an argument here that it won't happen or do I have to pull all this fiber out and run another 6" conduit 3 miles? Thanks in advance.
 
tom baker said:
770.133 talks about non conductive fiber cables, your concern is the armor, so it does not fall under 770.133
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With that being said, are the two armor cables as described above, particularly the fiber cable that has a PE jacket over the armor for outdoor use, good to route in a 6" conduit in a ductbank?
 
Flyinbryan said:
With that being said, are the two armor cables as described above, particularly the fiber cable that has a PE jacket over the armor for outdoor use, good to route in a 6" conduit in a ductbank?
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Is it already installed? Have you taken any voltage measurements from the fiber optic cable's armor to ground to see if there is any induced voltage?

Maybe you can disprove their argument with a multimeter.
 
Saturn_Europa said:
Is it already installed? Have you taken any voltage measurements from the fiber optic cable's armor to ground to see if there is any induced voltage?

Maybe you can disprove their argument with a multimeter.
Click to expand...
Yes, it's installed but not energized yet because they wont sell it off for the reason of routing. What I have is essentially two conduits inside one big 6" conduit.
 
As a last resort, rather than installing a new conduit you could install a fiber optic cable that didn't have the metallic sheath since it is in conduit then transition to an armoured fiber where it emerges from the conduit and is separate from the 120 cables.
 
I'll do one better than Tom...

Article 770 Part V, in which 770.133 is located, is titled "Installation Methods Within Buildings".

I've not seen a concrete duct bank ever considered "within a building". :D
 
Flyinbryan said:
Here is a unique situation I have I need help with. I have a fiber cable that is armor with a PE jacket for outdoor use. This cable does not carry a FOC or a FON rating due to it being for outdoor use. It was originally intended to be direct buried. The client decided to put it in a ductbank instead due to direct burial requirement in the specs being too deep. I created a 6" sleeve in concrete and I have put this armor fiber cable in the same conduit with a 600V power cable that is also armor and carrying a 110VAC circuit. Both are for CCTV camera use around the perimeter of a PE plant. They are saying I am in violation of NEC 770.133. However, this only pertains to indoor use rated cable that is always marked FOC or FON. The manufacturer of this fiber optic cable is saying the power circuit (110vac) can induce a voltage through the 600V jacket, through the armor around the power cable jacket , then through the PE jacket around the fiber cable into the armor of the fiber cable and create a safety issue. Do I have an argument here that it won't happen or do I have to pull all this fiber out and run another 6" conduit 3 miles? Thanks in advance.
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.

it's a durn shame there wasn't 30' of innershield slid
over those cables at each end of the duct bank.
if the duct bank had innershield, that would effectively
end the argument, would it not?

a durn shame.

if you pulled out the fiber, pulling in a mule tape behind
it, and used the mule tape to pull in an innershield into
the conduit, and then pulled that fiber inside of the innershield,
wouldn't that work?
 
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