Im looking at a Technical Paper from Chromalox a heater manufacturer among other things. and there are two examples for three phase circuits one is an open delta and the other is an open wye configuration. Just looking at the diagrams They looks exactly the same to me two resistances(elements) wired in series then a line voltage(phase) to each point one on each end and the third to the middle inbetween the elements?? however it is stated that for the delta version loss of a phase or element would reduce wattage output by 33% and for the wye it would reduce the output by 50%. what am I missing? the only thing really different is where they are measuring the Line voltage VL on the Delta they measure from one line to the centertap basically, on the wye it is across both heater resistances. any clarity would help thank you.:?