how can i calculate the no load power and no load current of a ac/dc motor from nameplate data?
In my opinion if we want to calculate (repeat, to calculate) the no load current, etc than we should be able find out all the required parameters for the development of no-load equivalent circuit of AC motor or DC motors For instance in case of AC Induction motor I suppose ,we should be able to determine the following parameters to make the equivalent circuit.:- (a) Primary and Secondary resistances (b) Primary and Secondary leakage reactances (c) Magnetizing loss resistance and magnetizing equivalent impedance (d) No load slip and equivalent representative load resistance In case of DC motor , I suppose we should be able to determine the field resistance, armature resistance, back EMF at no load speed, No load magnetic and friction losses Even though some of them may not be very difficult , however it would not also be a very easy task to map all these parameters. After 4 days some general corrections in sentences
On my experience, no load current of AC motor is about 40 % off nameplate (full load) current sorry for I don not have experience in DC motor
I think it is a matter of tesing the ac/dc motor by turning it on without a load and see what is Q (reactive power) representing the loses. Another way is if you know the full power S and the active power P and Q = S - P.
