How to determine the power when the nameplate of the motor is lost


When the motor nameplate comes off, there is no way to […]

When the motor nameplate comes off, there is no way to know the power of Taichuang Motor through the nameplate. At this time, you need to calculate it by measuring the resistance. If it is an ordinary standard motor, you can measure the center height, the mounting hole distance, and determine the frame size and shaft diameter. Then we can find the approximate power range by looking at the manual.
How to determine the power if the motor nameplate is dropped?
1. The motor can be powered on separately, of course, it also needs to be that common type. Then perform no-load operation, and measure the no-load current with a clamp meter. In general, the no-load current is about 30% of the rated current, so the rated current of the motor can also be calculated very well.
2. For single-phase motors, the size of the motor can be roughly estimated based on the starting capacitor and the working capacitor. Generally, capacitors have a capacity, which will determine the power range of the motor.
3. To know the power of the motor, we need to know the voltage and current of the motor. If it is a servo motor or stepper motor, the voltage may not be very standard, so it is difficult to judge. We can look for parameters from the end of the driver, which may be more ideal.
Of course, for ordinary motors and DC motors, if there are drives such as inverters and DC speed regulators, the specifications of the motors can be roughly judged by the parameters of the drives, because the power of the drives is generally equal to the rated power of the motor, or a higher level.
4. For the three-phase AC asynchronous motor, the domestic type is easier. Because the domestic three-phase power consumption is three-phase AC of 380 volts, you only need to know the current. Of course, the current needs to be measured on site. Generally speaking, the design of the motor will not run at full load, that is, the load current. Usually it should be within 80% of the rated current. The linear current of the motor is measured by a magnetic clamp, and the approximate rated current of the motor is obtained.
Finally, if your job is to repair a Taichuang motor, you can take it apart, look at the number of turns, the number of slots, the wire diameter, the core length, the number of windings, and the way out, and then compare the instructions to determine, but this method is for It is impossible for ordinary people.