.1 phase works as a neutral because in 3 phase each phase winding is 120 electrical degree apart so when field rotates some time they are negative and some time positive, so they do not measure 660 because 1 works as a neutral. T phase and neutral 220.3 phase = 380 volts because each phase 120 degree out of the other phase that's why its 380 volts not 440 and 660. E line=sq root 3( E phase )
Because the rotation angle phase is 120 degree. In addition to this,
this is mainly because it is phase voltage. Phase voltage will be b/w one phase or neutral. Phase voltage =line voltage/√3 where the line voltage b/w two phase.
