I suspect what most people call a hi-leg delta service is a open delta or two transformer setup with a lighting and power transformer with the 'B' phase being the end of the power transformer having the higher voltage to ground.
I think when I have calculated the fault current on these previously the B phase to ground fault was choked by the 1/2 winding in the lighting transformer making it lower than the A or C phase to ground fault.
I think when I have calculated the fault current on these previously the B phase to ground fault was choked by the 1/2 winding in the lighting transformer making it lower than the A or C phase to ground fault.