For a perfectly balanced load, with identical loads connected between each line conductor and the neutral conductor, there should be no neutral current. This is because the vector sum of three identical current, displaced by 120o, is zero.
However, for an unbalanced load, there will always be a neutral current because the vector sum of the currents will not cancell.
Measure the current and voltage on the secondary side.
There are situations where the secondary of a transformer is not grounded and the neutral is not connected to the neutral of the primary. This can cause a potential shock hazard so the secondary side needs to be protected.
since we need to get desired or rated voltage, so if it is connected in high voltage side of the transformer, voltage supply will be more, and hence the current will be more than the required amount. this is the reason why the instruments re connected at the low voltage of the transformer while performing no load test.
There is no 'standard' output current from a transformer. The secondary (output) current depends on the load, and should not exceed the rated secondary current. To find the rated secondary current, you divide the transformer's rated volt amperes by the rated secondary voltage. The above cited answer need more descriptive ; a) V/Z = I, b) V/Z = I + Magnetizing current of the transformer taken from Primary side of the transformer.
b'coz at the secondary side large amount of current flow by recarding of active component or other ckt. which is connected to the secondary side so that ckt. is not damage or burned by flowing large amount .. load is connected at the secondary side .AnswerThe 'primary' winding of a transformer is, by definition, whichever winding is connected to the supply, whereas the 'secondary' winding is whichever winding is connected to the load. This does not mean that a load MUST be connected to a transformer, as it will work 'off load' -that is, with no load connected- without any harm.