An electric heating element is rated at 4.0kW when connected to a single phase 240Vrms, 50 Hz AC supply, and is known to have a power factor of 0.833 lagging.
1. Calculate the current supplied to the heating element when connected to the 240Vrms AC source. Hence or otherwise determine the resistance and inductance of the heating element.
2. Sketch a phasor diagram for this operating condition, showing the applied voltage, load current and the voltages across the equivalent load resistance and reactance.
3. Determine the value of a shunt connected capacitance (μf) required to achieve unity power factor as seen by the supply. Determine the supply current and the real power absorbed by the heating element/capacitor combination for this operating configuration.