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william siegel
05-31-2007, 02:19 PM
Here we have four 4/0 service cables. The one in the lower left has been capped with duct tape and and a smaller cable installed. I am assuming this is a three phase system due to the four wires (and yes, I know I should never assume). I rarely see this set up so:

1) Is this a 3 phase system

2) why would anyone disconnect that one wire and replace it with a smaller wire

3) what implications / dangers does this set up pose.

James Duffin
05-31-2007, 02:47 PM
What type of structure is this? A house or commercial property? Also is there a cabinet to the right of the meter base?

Thom Walker
05-31-2007, 02:53 PM
It looks like it was three phase service used as single phase.
I like the duct tape. So that's what it's used for?:D

william siegel
05-31-2007, 03:16 PM
This is actually a home that Tony Martin (New York Jets) purchased for a family member.
There is nothing to the right of the meter base.
Maybe they were growing somethey they shouldnt have. I was just stumped on this one and looking for some feedback

James Duffin
05-31-2007, 03:36 PM
My guess is that the larger neutral wire at the top of the panel used to be the third phase wire at the empty right lug at the bottom of the panel. The smaller neutral wire at the top was the original reduced neutral. The smaller wire on the left bottom lug is there because the lug in the meter base is damaged. I would guess that this is not the main panel for the house and is a panel in a service area. The panel is a mess for sure!

Jerry Peck
05-31-2007, 04:56 PM
The panel (I'm not calling it "service equipment" because it is not allowed for use that way as "service equipment") is a 3 phase panel.

That said, that's a single phase service entering it.

The larger phase conductor in the middle typically is (when a three phase panel is used for single phase) installed on the right and left main lugs, leaving the center phase bus not used. But ... one could chose to use any two of the three buses for the mains, and who ever wired that chose the left and the center.

It looks like, for whatever reason, the left phase conductor was abandoned (not properly) and another smaller phase conductor installed.

I am basing the above on the fact that this looks old and the abandoned phase conductor looks like it was abandoned more recently, meaning it worked well for many years. (An assumption I am making.)

In that case (*IF* that is the case), why was the phase conductor replaced with that small one? The only conductor the person who screwed with this had laying around handy?

Did you measure voltages?

Whenever I would find something 'unusual' in anyway like that, I would measure voltage, to try to figure out if they had 120/240, 120/208, I've even been known to stick my volt meter probe down into those abandoned wires to see what voltage they had on them.

There are WAY TOO MANY breakers (you have to count the empty slots too, because they *could be used* in the future) for this to be proper "service equipment".

However, in reality, *IT IS* being used as the service equipment, so the number of main disconnects (I count about 24 potential disconnects in there) is really all screwed up - from day one, long before that phase conductor was abandoned.

Notice the seal missing from the meter? Did you pee in there? Is it missing *because you did*? :D

Maybe I'm just to used to prying and peeking into place I should not? :)

James Duffin
05-31-2007, 06:02 PM
In this house there would most likely be a service equipment area and a service area. The service equipment area would be where the electrical service is located and the service area would be where the mechanical equipment is located. Most of my life has been spent in the service area of large complexes. I'm back door company. Very seldom ever saw the lobby.

James Duffin
05-31-2007, 06:08 PM
That small wire could also be the "free power" wire connected to the line side of the meter...

william siegel
05-31-2007, 08:01 PM
Just to clarify - this is the service equipment. There are two 100 amp breakers and a 200 amp breaker for the three distribution panels inside. Good catch on the seal missing Jerry, but no, I did not peek in there.

James Duffin
05-31-2007, 08:12 PM
If this is the service equipment then you have an unfused #4 (guess) feeding a potentially 300 amp load. Could need an electrician for repair.