*As I recall on a delta connection one of the phases will have a higher
reading to ground than the other two. On a Y connection the reading to
ground will be the same. In NJ, Public Service Electric and Gas will not
permit that high leg to be installed in the same panel as the neutral.
The NEC allows it though.

What you are describing sounds to me like a 240V "star" system with high
leg, a variant of Y. Two of the phases are 240V center tap with the
center
tap connected to neutral. That provides four 120V legs. The third is
240V
with one end rather than the center tap of that transformer's winding
connected to neutral to provide the "high leg". It is possible to use the
center tap of that to provide a fifth 120V leg.


*It's been a while since I have worked on three phase, but I seem to recall
on a three phase 240 volt delta system, the high (Orange) leg is around 180
volts to ground. I only remember one phase as being center tapped. Next
time I meet with someone from the power company I will ask them to refresh
my memory.