What to use in place of capacitor in capacitor spit motor?
Answers
If inductor is used, the motor would not start even if having same reactance. Since coils are inductive so a capacitor or some phase splitting (advancing is necessary). Moreover, a high valued inductor can split the phase of the existing windings but it wont be a good practice to add an inductor of high value to split the phase (incurring low pf and losses).
Answer:
There are two capacitors in this motor represented by CS and CR. At the starting, the two capacitors are connected in parallel. The Capacitor Cs is the Starting capacitor is short time rated. It is almost electrolytic. A large amount of current id required to obtain the starting torque. Therefore, the value of the capacitive reactance X should be low in the starting winding. Since, XA = 1/2πfCA, the value of the starting capacitor should be large.
The rated line current is smaller than the starting current at the normal operating condition of the motor. Hence, the value of the capacitive reactance should be large. Since, XR= 1/2πfCR, the value of the run capacitor should be small