Answer Posted / ajit
iF THE THREE PHASE FAULT NOT INVOLVING THE EARTH THE
VOLTAGE ACROSS THE CIRCUIT BREAKERPOLE. FIRST POLE CLEAR
105 TIMES THE PHASE VOLTAGE IN 3 PHASE AC CIRCUIT BREAKER
ARC EXTINTION IN THE THREE POLE IS NOT SIMULTENEOUSLY AS
CURRENT IN THREE PGASES ARE MUTUALLY 120 DEGREE OUT OF
PHASE. HENCE THE POWER FREQUENCY RECOVERY VOLTQAGE OF THREE
PHASE IN WHICH ARC GETS EXTINGUISHED FIRST IS ABOUT 105
TIMES OF PHASE VOLTAGE.FIRST POLE TO CLEARE FACTOR IS THE
RATIO OF VOLTAGE BETWEEN HEALTHY PHASE TO FAULTY PHASE TO
NORMAL PHASE VOLTAGE.
| Is This Answer Correct ? | 11 Yes | 4 No |
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