A single-phase motor may hum but fail to start due to various reasons. One common cause is a faulty capacitor, which hinders the motor’s ability to generate sufficient torque for starting. Additionally, issues with the starting switch or centrifugal switch can impede the motor from transitioning to the run mode.
Another possible factor is a locked rotor, where the motor’s rotor faces resistance preventing it from turning. This can be attributed to mechanical obstructions, bearing problems, or inadequate lubrication. In some cases, a damaged or worn-out start winding could also contribute to the humming without starting issue.
Furthermore, voltage fluctuations or an insufficient power supply may lead to the motor humming but not starting. It’s crucial to ensure that the motor receives the correct voltage and that there are no irregularities in the power source.
In summary, the humming of a single-phase motor without starting can be linked to problems such as a faulty capacitor, issues with the starting or centrifugal switch, locked rotor due to mechanical reasons, damaged start winding, or inadequate power supply. Identifying and addressing these issues can help resolve the problem and allow the motor to start properly.
