Question use of 3/8 Flexible Metalllic Tubing

[monte]

This is in a commercial building. This future bar was wired completely with 3/8 Flexible Metallic Tubing. I thought that 3/8 Flexible Metallic Tubing could not exceed 6' in there use. The 3/8 AC is acting as the ground for this system because there is no ground wire in the AC.

This system has been passed by our Code Inspector and was installed by a Electrical Contractor. Is this a proper method of wiring for a commercial building or any other type of structure?

[Jim Katen]

Originally posted by monte

This is in a commercial building. This future bar was wired completely with 3/8 Flexible Metallic Tubing. I thought that 3/8 Flexible Metallic Tubing could not exceed 6' in there use. The 3/8 AC is acting as the ground for this system because there is no ground wire in the AC.

This system has been passed by our Code Inspector and was installed by a Electrical Contractor. Is this a proper method of wiring for a commercial building or any other type of structure?

Monte,

Flexible metallic conduit and armored cable are two different things.

You're correct about 3/8 inch FMC being limited to 6 feet. In fact, there are a bunch of other limitations on conduit this small. Check out article 348.

I believe what you saw in this building was armored cable. You can run this stuff as far as you want (within the limitations of voltage drop, of course). Read all about it in article 320.

It's perfectly ok to use the cable sheathing for equipment grounding.

- Jim Katen, Oregon

[monte]

Thanks Jim, I figured if someone had the right info, you would.