Running long underground line without neutral or safety ground using transformer, is it to code?
Thanks for article @JONK  March 8th,  on grounding between buildings.  I think where the danger still exists with the isolation transformer is that on the primary side with only the 2 hot conductors;  if one of the those conductors shorts to the transformer case,  there is no path to the source ground to trip a circuit breaker on the primary side of the transformer.  Also the local ground rod at the transformer secondary is not a good enough path to the source voltage to trip the primary breaker.  So I need to also run a bare copper ground wire with my 2 conductor 6 awg direct bury cable.   Another thought; even if the hot primary does short to the transformer case,  one would not feel it for the same reason, there is no path back to the source ground with low enough resistance to flow any current.   i.e.  the case would float at 120V with no path to flow any current/shock anyone.   Not safe per code, but just thinking of what would happen.