Question: how to calculate electrical load in ampere?
Answer: I(A) = P(W) / (√3 × PF × VL-L(V) ) So amps are equal to watts divided by square root of 3 times power factor times volts.
amps = watts / (√3 × PF × volts) or.
A = W / (√3 × PF × V) Example. ... 
I = 330W / (√3 × 0.8 × 110V) = 2.165A. Amps calculation with line to neutral voltage.