POWER DISTRIBUTION SYSTEM

DO YOU KNOW THAT IN 3 PHASE- 4WIRE SYSTEM, IF THE VOLTAGE PER PHASE IS 220 VOLTS THEN MATHEMATICALLY MAKE 660 VOLTS (i.e 220 X3 =660 VOLTS ), BUT WE MEASURES IT 440 VOLTS INSTEAD OF 660 VOLTS ?

ANS:- WE KNOW THAT IN 3 PHASE POWER SYSTEM, WHEN WE DRAW SINOSOIDAL WAVE FORMS  OF ALL THE THREE PHASES, IT SHOWS THAT AT ANY INSTANT 1ST PHASE ON +VE PEAK, 2ND PHASE ON -VE PEAK AND 3RD PHASE ON NEUTRAL POSITION. AND THIS POSITION CHANGE ON EVERY INSTANT. SO IF WE ASSUME FOR A INSTANT THAT THE 1ST PHASE ON 220 VOLTS ( +VE SIDE ) AND 2ND PHASE ON 220 VOLTS (-VE SIDE ) ( 220+220 = 440 ) AND THE 3RD PHASE WILL BE ON NEUTRAL POSITION. 

PLEASE SEE AND UNDERSTAND IMAGES BELOW