The installer missed the obvious jumper location: at the bus lugs at the top, still unused.
Our man has jumpered A and C phases ( Black and Blue )
Putting '#2' at position #3 is too cute.
Said jumpering will not produce any single pole breaker with a voltage of 0. All will show full voltage.
Double pole breakers will only show 0 volts when tapping Black and Blue. Red/Blue and Black/Red combinations will deliver full voltage.
Such a set-up makes one think that the panel was boosted from a commercial job way back when. The price difference would always stop a legitimate player from wasting a three phase panel so.
Alternately, it's a second hand panel rigged up by a tradesman. Still, a waste of value.
