The internal loss generated when the motor converts electrical energy to rotational movement becomes heat, making the motor hot. The motor temperature is expressed as the ambient temperature plus the temperature rise caused by loss within the motor. If internal loss within the motor is 50°C and the ambient temperature is 30°C, the surface of the motor will be 80°C. This is not abnormal for a small motor.
The torque produced by the motor is affected by changes in power supply voltage. The torque produced by the motor is proportional to roughly the square of the power supply voltage. For example, if the voltage of a motor rated at 230 V fluctuates between 207 V (90%) and 253 V (110%), the torque produced will vary between 80% and 120%. When using motors under large power voltage fluctuations, remember that the torque produced will vary, so select a motor that provides a sufficient margin.
A reversible motor is not simply an induction motor with a simple braking mechanism added. The ratio of coils between the primary and the secondary coils in a reversible motor is different from that of an induction motor. The simple brake mechanism is added to the rear of the motor. The capacitor’s capacitance is also increased to increase the starting torque. This means that if only the brake mechanism is removed, the reversible motor will not be usable at a continuous rating like an induction motor; it will simply lose its holding power and its reversing characteristics will be reduced.
Reversible motors require a larger input power than induction motors to increase the starting torque and improve the instant reversing characteristics. This means that loss is high and the temperature rises more during continuous operation. If operated continuously, the motor will burn out. It is thus designed to provide maximum performance if operated for no more than 30 minutes continuously.
The speed of single phase (AC) induction motors and reversible motors is determined by the power supply frequency. To change the speed of induction and reversible motors, the power supply frequency can be changed using inverter control or gears and pulleys can be used. If your application requires changing speed, we recommend a speed control motor.
Almost all of China Motor’s standard compact AC motors that fall within the broad group of single-phase induction motors are “capacitor-run-motors”. To run an induction motor, a rotational magnetic field must be created. Capacitors perform the role of creating a power supply with the phase shift that is required for creating such a rotational magnetic field. Three-phase motors, by contrast, always supply power with different phases, so they do not require capacitors.
The capacitor that comes with the motor has a capacitance that was selected to work optimally with the motor. When another capacitor is used, it should be a motor capacitor with the same capacitance and rated voltage as the capacitor that comes with the motor. Electrolytic capacitors may not be used.
Gearheads reduce the motor speed by 1/3 to 1/180. They do not, however, reduce the speed with a single gear, but with several. The number of speed reductions depends on the gear ratio, so the direction of output shaft rotation differs.
Extreme changes in temperature may lead to condensation within the motor. Should this occur, parts may rust, greatly shortening the service life. Take measures to prevent condensation.
A gearhead with a gear ratio of 1/180 must be connected to two decimal gearheads with a gear ratio of 1/10. The permissible torque is the same as if the 1/180 gearhead were used alone. The mounting screws must also be longer.
China Motor lubricates the surface of gears in gearheads with grease. Oiling is not required.
In order to turn a single-phase induction motor, it is necessary to use a capacitor to create two power supplies with different phases to obtain the rotating magnetic field. Therefore, if the capacitor is not properly connected, the phenomenon described occurs. Check for a cut line or contact defect in the capacitor section. The way to check is to measure the voltage across the capacitor terminals and check whether or not it is at least 1.5 times the power supply voltage. If not, the capacitor may not be working properly.