Applications of capacitor start single phase induction motor
When the motor reaches about 75% of its rated full load speed, the start winding and start capacitor are disconnected from the circuit by an automatic switch.
Belt driven fans are typically less efficient due to belt and bearing losses.
Selection of larger, slower moving belt driven fans will generate less noise for a given application.
Smaller direct drive fans will have a faster rotating wheel for the same air delivery and be more efficient, however generate more noise.
The overall benefit is not having t deal with special design requests that result in unnecessary extra expense and longer lead times.
Most often the fan manufacturer will recommend the proper standard motor for the application.
A major advantage of the PSC motor is the capability of operating at different speeds by allowing higher levels of slip.