sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Armored Telephone/Catx Cable?

While I was out yesterday, I happened across a payphone. I hadn't really given them much thought over the years, other than their almost extinct status in this area. Anyway, I was looking at the armored cable on it, and wondered if that was ever installed in lengths longer than two feet, that is, to cable a building.

Is armored telephone cable just for payphones, or does it have uses elsewhere?

Jack

Armored handset cords on payphones (I assume that's what you are talking about) is a pretty specialized product that does more than just protect the cable. It's pretty resistant to pulling and stretching and also corrosion resistant. Premises wiring would not require something that goes that far but there is armored premises wiring that is much like electrical type AC in construction.

-Hal

The only other places I've seen that type of armor is on flexible connectors used for alarm system wiring. They are often used between a fixed wall and a moving door.

They did make longer armored handset cords. They were used for handicapped or "phone from car" phone booths. I believe that they came as long as 5 or 6 feet.

I have seen armor handset cords on phones in the psychiatric section of hospitals.

I was just working on the phones there of course..........

This is what you are looking for.

-Hal

I wonder if you could also just buy greenfield and put your own cables in it? Wonder how it prices out compared to armored cable pre-made?

You could- except long lengths are going to be a real PITA to pull the wire through. If you look at the outside diameters they are smaller than the smallest (3/8) Greenfield also. I can't believe that there would be much of a price difference considering labor.

If you need the entire run armored this is whe way to go. If you just need to protect a section then Greenfield is the way to go.

-Hal

When I did the job at JFK airport we got the Belden Speaker cable in both armored and unarmored versions on large wooden reels. The armored looked just like MC (BX) electrical cable.

For large runs we ran pipe and for single runs we used the armored version. If we had to "armor up" some of the loose cable we used 3/8 greenfield and it was, as Hal said, a royal PITA.

It was almost easier to run tubing.

Sam

Michael:

Thanks for the replies everyone. Hal, thanks for the link. I'd seen armored comm cable in catalogs before, I just couldn't think of a reason of putting it in a building instead of running conduit (cost, I guess). Aside from payphone handset cords, and what Ed mentioned about door alarm wiring, I've never seen it in a building before for v/d/v. Terminating it looks super fun - not. I'm sure that with the correct tool to strip back the mc it isn't *too* bad though.

Jeff, I was thinking FMC was limited to 6', but 348.20 appears to say otherwise. If possible, I'd rather use ENT than FMC, or EMT stubs where protection is needed. The only time I use flex is for whips from a junction box to elevator control cabs.

Sam, I bet it was a pita. Did you have to fish every piece of it?

Jack

Well almost of it was for ceiling speakers so we just had to pull it through the ceiling - no fishing in walls.

Thinking about this reminded me that in the early '80s when Plenum cable first was required we got some cable for one job that looked like conduit on a reel. It was PVC - 25 pair and quad that was covered with a thin layer of aluminum. Stripping it was a nightmare. You had to sharpen your knife after each cable. And pulling it through the ceiling was bad, but pulling it down a conduit stub was almost impossible.

Sam