The supply is from 2MVA Transformer which is a common distribution transformer for various loads.
It is solidly ground,2MVA 6.6KV/415V,DELTA/STAR.
The transfomrer in question has neutral floating as per the drawing of battery charger.
Actually the transformer was tested outside the battery charger.It is a spare transformer and was to be tested before using it in the charger.
specs. of transformer:
95KVA,Y/DELTA,415/140V
CASE 1:GIVING 3-PH AND NEUTRAL SUPPLY TO PRIMARY:
AT NO-LOAD:
PRIMARY VOLTS PRIMARY CURRENT
RY=401.7...
Recently we purchased a star Delta trafo for battery charger.
when testing the trafo at site for ratio test,we gave 3ph and neutral to primary and measured the respective voltages and currents.
Surprisingly we got current in the neutral inspite o balanced voltages.
Then, we retested using only...
