What are the reasons why industrial large ceiling fans are slowing down?

In the hot summer, industrial large ceiling fans play an incomparable role in our lives, but large ceiling fans will also fail after a period of time, the most obvious is that the speed of the ceiling fan slows down. There are many reasons for the slow speed of the ceiling fan, but there are four main reasons in summary.
1. The governor is broken
If it's new, it's probably a broken ceiling fan governor.
2, bearing oil shortage
If the fan bearing is short of oil, it can be added to the oil (use butter). If it is a short circuit between turns, the motor will overheat, and it must be re-wound. Judging whether there is a problem with the bearing can listen to the sound, and the bearing has a problem must be called professional maintenance personnel.
3. Capacitor capacity decreases
Most household appliances are powered by single-phase power supply, but electrical appliances with motor must have two or more phases of power supply, how to do? The designer has long thought that in the single-phase circuit, a large capacitor is connected in parallel, because the large capacitor has a hysteresis effect on the current for the AC power supply (the circuit with capacitance is 90 degrees higher than the circuit current without capacitance), so that the original one-phase input becomes two phases, and the motor can work normally. We use household appliances (single-phase) are the same principle.
The capacitance value becomes smaller or the lack of oil friction is large or the turn short circuit, the capacitance value becomes smaller, and the capacitance value can be appropriately increased, but it cannot be too large, otherwise the motor temperature will rise, affecting the motor life. This is a synchronous motor, the speed is determined by the frequency of the power supply, if there is no page 100 RPM, the blade is also 100 RPM, if you install more than a few leaves, the load is too heavy, the motor can not start, the spring is repeated to help start.
In addition, the slow speed of industrial large ceiling fans is not necessarily a problem of capacitors and bearings, and the capacitor is to ensure that the fan can rotate in the direction of advance rotation. Check whether the wind blade is deformed, and the reduction of the wind surface will affect the air volume. Also check whether the governor contact is not good, so that the gear is in a low position.