Can the electric fan motor connect two capacitors in parallel?

The electric fan motor can be connected in parallel with two capacitors.

1. First, the withstand voltage of two or more capacitors should be more than twice the rated voltage. For example, a capacitor with a rated voltage of 220v needs to have a withstand voltage above 400v V.

2. Secondly, the sum of two or more capacitors is equal to the capacity of the original capacitor. For example, the Three Gorges electric fan, originally 2UF, can connect two capacitors of 1UF in parallel (note that they are connected in parallel). If it is a relatively large electric fan, the rotation speed is relatively slow, and the capacitance can be appropriately increased by about 1UF.

Fan capacitors are generally divided into two types: starting capacitor and working capacitor, and the function is to press the function when the capacitor works. The starting capacitor assists the motor to start when the motor starts, but it has no effect when the motor starts. The working capacitor still helps the motor to run after the auxiliary motor is started, that is, it still works. The capacitance of an electric fan is generally the starting capacitance.

Methods and steps of self-service maintenance of electric fan capacitors;

First, the maintenance of the electric fan motor does not turn. The main reasons why the motor does not turn are: open winding, oil shortage and abnormal capacitance. From the maintenance practice of electric fans, the latter two kinds of faults are mostly. For the non-rotating electric fan, my maintenance steps are: plug test, motor rotation, capacitance measurement and reprocessing.

1. Measure the operation and speed regulating winding of the electric fan. Start the electric fan timer first. When you hear the click, the timer is normal. If there is no tick, the timer is broken. If there is no resistance value, it may be that the motor winding is burnt out and open. For the motor with thermal fuse in series, it may be that the thermal fuse is open, so take the motor apart and have a look. If it is only an open circuit, it can be restored to normal by short-circuiting the thermal fuse. The gear switches are all broken, but it is unlikely.

2. Measure the starting capacitance. If the motor shaft rotates flexibly, measure the starting capacitance of the electric fan motor. First, measure the resistance values of the running, starting and speed regulating windings of the whole electric fan motor, that is, the resistance values of the black and yellow leads, at both ends of the capacitor with a multimeter R×100Ω.

3. Check whether the shaft is locked, remove the electric fan cover and turn the motor shaft by hand. If it does not turn, the motor is severely locked. Dismantle the motor, first remove the oil stain and rust on the front and rear shaft sleeves and the motor shaft, and then fill the linoleum of the front and rear shaft sleeves with sewing machine oil. Most electric fans can troubleshoot.

Second, for example, the remote control function of the floor-standing remote control electric fan is basically normal, but after the electric fan is turned off, the electric fan will make a buzzing sound when touched by hand, especially at night, when the blades of the electric fan are slowly rotating. For the electric fan whose motor can move, I can do it in one step according to the actual situation. Instead of step-by-step maintenance as mentioned above.

If the user says, the electric fan turns slowly first, and then gradually becomes faster. According to experience, the motor is generally slightly shaft-locked. The reason is that the electric fan was originally short of lubricating oil. Disassemble the electric fan motor directly and add enough sewing machine oil to the linoleum of the front and rear shaft sleeves, which can generally be repaired. Troubleshooting of remote control electric fan that can be turned on immediately after power-on. At present, the control actuators of remote control fans are basically silicon controlled rectifier. It can be seen from the principle that the thyristor is essentially equivalent to the breakdown and conduction of the switching thyristor. Of course, the electric fan will turn after being electrified.

reference data

Love to ask. Ai Wen [reference time 20 17- 12-27]