I have a building with two services. One 3 ph 240v Delta, the other single phase.
The single phase is 400a (all irrelavent to this topic) which has two 200a panels which are FULLLLLLL!
Three phase service is mostly 2pole and three pole breakers in a 200a panel.
Trailer was attached to building in rear for more space. Has its own panel.
No room from the single phase service to feed so the sparky at the time installed a 240/480 hi to 120/240 lo transformer.
The nameplate doesnt say it, but I assume it is delta to wye, because hi side has no neutral tap. 2 legs with chassis ground run. Lo side has neutral tap which goes to the trailer.
How much neutral though do we actually have? It cant be 100%
