I AM PROVIDING TRAINING FOR OUR PLANT ELECTRICIANS, AND I WANT TO CONFIRM A COUPLE BITS OF POWER THEORY PRIOR TO GOING LIVE.

EXAMPLE: 13,800V DELTA, 480-277V WYE, 2000KVA

TRANSFORMER.

X1 HAS 1000 AMPS

X2 HAS 1200 AMPS

X3 HAS 1400 AMPS

I HAVE ASKED THEM TO CALCULATE:

NEUTRAL CURRENT

ALL 3 DELTA LINE CURRENTS

ALL 3 DELTA PHASE CURRENTS

TO SOLVE FOR NEUTRAL CURRENT;

THE SQUARE ROOT OF...

1000 SQUARED + 1200 SQUARED + 1400 SQUARED

= 2098 AMPS

DELTA PHASE A CURRENT = 1000A/49.819 = 20AMPS

............B CURRENT = 1200A/49.819 = 24AMPS

............C CURRENT = 1400A/49.819 = 28AMPS

49.819 IS 13800/277.

DELTA A LINE CURRENT = 20 X 1.732 = 35AMP

......B LINE CURRENT = 24 X 1.732 = 42AMP

......C LINE CURRENT = 28 X 1.732 = 48AMP

I REALIZE THAT WITH THESE IMBALANCES, THERE WILL BE PHASE SHIFTS, BUT 120 DEGREE ANGLES WERE USED TO SIMPLIFY.

I HAVE A 50/50 CONFIDENCE LEVEL WITH MY CALCULATIONS.