How much current is drawn by primary coil of transformer whch steps down 220 to 22 volt to operatea?

Question

device with an impedance of 220 ohm?

Answer 1

You can calculate the current (drawn) in the primary if your given impedance is referred to primary...by ohms law.



Iprimary = 220V/z prim



assuming it is referred as primary impedance



= 220/220 = 1 amps (approximate because you did not give the reactance or resistance)

Answer 2

Approximately 1/10 of the current on the secondary side, which you can easily calculate from Ohm's Law. When voltage is stepped down, current is stepped up proportionately.

Answer 3

Joel is right. It comes out to be 10mA assuming 100% transformer effeciency and not taking inductance and leakage involved in transformer modeling into account (which you did not specify anyway).