interesting ground wire

hawkestone · 07-17-2006, 01:18 AM

Hi All:

I just discovered something and am looking for help from all you electricians.

I have a wire going from my panel to a junction box in my ceiling and no-where else.

I decided I would use this for an extra outlet in my store. But when I went to connect the wires - Black to Black - White to White - Ground to Ground and box-- there is a thin - looks like aluminum -- flat peice of wire where the ground should be.

Is this a proper ground?

Any advice would be appreciated.

Thanks

iqchicken · 07-17-2006, 10:55 AM

Does the flat wire look like this ?

hawkestone · 07-17-2006, 01:23 PM

No,

It is just a flat peice of aluminum.

It was folded over and securely clamped with the box clamp that holds the wire from being pulled out of junction box.

The wire I should mention is the metal wrapped sort.

Kerrylib · 07-17-2006, 02:22 PM

Is the "wire" you're talking about, actually armored cable?

When you look at it is it a metal spiral, with insulated wires inside?

Sounds like the "ground" wire you are refering to is the ground inside the armor sheath. Or at the very least it is flex conduit with a ground. Even though the flex conduit is metal and conducts well, it needs a ground wire because the spiral configuration creates a high inductance (if i remember correctly). Anyway it doesn't cut it to just clamp the flex conduit to the box.

hawkestone · 07-17-2006, 03:59 PM

It is armoured cable, - the outside has the spiral metal you're referring to,

Inside it has

White wire
Black wire
Red Wire
Flat aluminum strip type thing

Square Eye · 07-17-2006, 04:15 PM

I noticed that you are in Canada.
That may be something that we don't see in the lower 48.

petey_racer · 07-17-2006, 04:32 PM

This is AC (BX) cable. It was/is VERY common in the states, especially in commercial settings. The AL "wire" is the bond strip. It helps keep a continuous ground path in the cable sheath.

It is meant to be wrapped back on the sheathing before the cable is put into a connector. It is NOT a ground. It DOES NOT get terminated anywhere on any device or ground bar.

Square Eye · 07-17-2006, 05:27 PM

There's far more MC here than BX. MC has a green insulated grounding wire in it.

hawkestone · 07-17-2006, 05:32 PM

So if it is not a ground wire,

Where is the ground wire -- should there not be one?

petey_racer · 07-17-2006, 06:45 PM

MC is a relatively new thing. By this I mean 15 or 20 years. MC is the standard these days.
There is not much BX being used anymore. It was used widely in the past.

The metallic spiral sheathing IS the ground. Like I said, the strip just gets wrapped around.
Make sure all your connectors and box clamps are made up clean and tight.