Hi,

I have problems on 3 phase systems,

what is the purpose of connecting the load star point to the supply neutral current while setting currents taken from supply?

 

You tie the load star point to neutral to ensure the line-to-neutral load voltages are equivalent to the supply line-to-neutral voltages. A floating star point on an unbalanced (in particular) 3-phase load would lead to imbalance of the load line-to-star point voltages and hence unexpected load phase current values. It's sound procedure.

 

Ohh Thanks very much!! i have another question when comparing results with the 2 or 3 watt meter methods, why is it necessary to disconnect the neutral?


thanks alot!!