Armored Fiber Optic Cable Grounding

[tom baker]

I have some Corning armored direct bury fiber optic cable, its about 1/2" OD. This is my first application of armored FO cable...what kind of bonding clamp do I need for the cable sheath?
I don't see anything in the Corning catalog

 

[mopowr steve]

It’s fiber optic why does it need grounding?

 

[jumper]

It’s fiber optic why does it need grounding?

Armored Metal Clad....the sheathing.

 

[jumper]

Best I could find out is that this clamp....maybe...is what is needed.


https://www.discount-low-voltage.co...-jC7T4INueGUMihGBF3oQOxue9YH6JMRoCKRcQAvD_BwE

Or this kit which the above and more.

https://www.discount-low-voltage.co...EpvbIZBrTKXEWX5AKfk3v4GriPsX5mPxoCNkAQAvD_BwE

I did not go to the 3M website and verify. Some Corning person mentioned them in an article. Lost the link, sorry.

 

[hbiss]

Without seeing the cable I would say that the second of those shield bond clamps is what you need. I've used the first on copper cables many times which their video shows you how to do. I have never done fiber and there doesn't seem to be a video for it. I'm sure it's similar but the description talks about the strength members and there are extra parts.

It just might be that you can use the first one depending on your installation.

-Hal

 

[mopowr steve]

What’s likely to energize it. And if something did there is no effect to the optic strand. Is it just for rigidity?

 

[gadfly56]

What’s likely to energize it. And if something did there is no effect to the optic strand. Is it just for rigidity?

Some of these are listed for indoor/outdoor, so you don't have a demarc box. You don't want something happening at building A to get to building B and vice versa.

 

[hbiss]

I've never seen armored FO cable so I can only surmise that it's there for physical protection. I do suppose that there are applications that have electronics at one or both ends that could use the armor for a ground path or bond.

-Hal

 

[gadfly56]

I've never seen armored FO cable so I can only surmise that it's there for physical protection. I do suppose that there are applications that have electronics at one or both ends that could use the armor for a ground path or bond.

-Hal

See here for an example. A similar product is being used on a current project of ours.

 

[mopowr steve]

See where it say’s “requires no grounding or bonding”

 

[Adamjamma]

See where it say’s “requires no grounding or bonding”

I missed that but saw it does not want crushed or bent beyond certain radius in the assembly of whip instructions...

 

[hbiss]

See where it say’s “requires no grounding or bonding”

The armor is not used for shielding so there is no need to ground for that aspect. If the cable is installed outdoors the NEC does not cover it. However, where it enters a building (or if it's run within a building) Article 770.93 applies which requires bonding of the metallic armor (or interruption of it) as close as possible to the point of entrance. So in that respect you kind of do have a "demarc" like copper or coax.

-Hal

 

[kwired]

What’s likely to energize it. And if something did there is no effect to the optic strand. Is it just for rigidity?

I would say gives it a little rigidity, possibly some rodent resistance for direct bury applications, also is a conductive path that works great for connecting a locator when needed down the road.

The armor is not used for shielding so there is no need to ground for that aspect. If the cable is installed outdoors the NEC does not cover it. However, where it enters a building (or if it's run within a building) Article 770.93 applies which requires bonding of the metallic armor (or interruption of it) as close as possible to the point of entrance. So in that respect you kind of do have a "demarc" like copper or coax.

-Hal

I can agree with that.

 

[tom baker]

What’s likely to energize it. And if something did there is no effect to the optic strand. Is it just for rigidity?

I am concerned about lightning, inducing a voltage which follows the armor to my equipment