How to calculate the Power Factor of a telephone set, and how does it effect the Ring Generator?
Telephone ringing elements include resistance, capacitance and in some cases inductance elements. A ringing element’s Power Factor (PF) expresses the amount of phase shift between the AC voltage and the AC current caused by the device. The PF is a function of the ratio between the real and imaginary elements of the ringing element’s impedance. Higher capacitance or inductance components in comparison to the resistance component will cause a larger phase shift and be expressed as lower PF. A PF of 1 will cause no phase shift, and indicate that the device has no capacitance and inductance elements, or that both exist and exactly cancel each other’s effects. The PF of a ringing element, which includes resistance in series to capacitance, can be obtained by using the following equation: Higher phase shift between the Ring Generator’s output voltage and current will cause its output stage to absorb more energy and to generate more heat. PowerDsine Ring Generators are specified for PF=0.5 an
