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George

On 1/13/2013 10:20 AM, wrote:
On Jan 13, 10:01 am, wrote:
On Sun, 13 Jan 2013 05:57:42 -0600, wrote:
A large store downtown has a heavy FOUR wire triplex feeding the
building. 3 wires are black insulated, the other is the bare neutral.

The thing that caught my attention to it, is that the 4th wire is not
connected to anything. All the triplex I've ever seen is 3 wire, two
are insulated, one is bare. That's for a standard 240V single phase
system.

Im thinking that this cable was intended to be for three phase wiring.
Three hot, and the neutral. Is this right?
Maybe that building once had 3 phase service, or they just had that
cable on hand when they wired it, and used what they had...

That says "3 phase".
Three hots and a neutral.

Did you read the part where he says the "neutral"
is not connected to anything? Sounds like a support
wire to me.

The version on the newsserver I use does not mention anything about the
"neutral" being unconnected.

You can verify it by looking at the transformers.
If you see 2, one perhaps bigger than the other, it is 3 phase center
tapped delta. (AKA red leg or wild leg)http://gfretwell.com/electrical/red%...ansformers.jpg

If you see 3 equally sized transformers it is usually 3p wyehttp://gfretwell.com/electrical/3%20p%20wye-wye.jpg