First, if the detection of three-phase AC motor is good or bad
1, shake shake, 500V shake table can shake the three terminals of the wire on the motor shell insulation resistance, it should be above 0.5M Europe no short circuit to ground (Yantai motor repair).
2, multimeter test: measured A / B / C between the three-phase resistance, whether equal, should be about the same, poor too much can turn, but not long, remember that the greater the motor, the smaller the resistance! But Can not be three-phase are 0 Europe, unless you are particularly large, such as more than 50KW motor! Remember that if the speed of the six terminals of the motor resistance can be different
3, check the bearings, fans, general let the whole motor wrapped around! Because sometimes bearing will also burn the motor lock
4, the motor’s no-load current is generally 10% to 50% of the rated current, and sometimes the motor idling current is also zero
5, the motor rated current operation, is full load operation, the output power is basically 100%. Operating current is small, indicating that the motor output power becomes smaller, is light-load operation.
Second, how to detect the exchange of single-phase motor is good or bad
Use 500V megger to measure the insulation resistance of the motor windings and the shell, should not be less than 0.5 Megohms; with a multimeter to measure the windings of the leads, there is no disconnection; the above meet the requirements of the motor is good.
Detect the quality of the capacitor with a pointer multimeter to facilitate some (also have a digital file with a capacitor, can be measured directly).
1K 10K or appropriated multimeter resistance profile, the two lead sensing capacitor, the capacitor is slowly returned to the left to the right hands fast steering is good; always toward the right DESCRIPTION capacitor breakdown; pointer does not move, the capacitor Internal disconnection or no capacity. Use this method can only judge the capacitor is good or bad.
Three DC motor is good or bad
Have a look first break, measuring resistance is normal.
If you have a brush DC motor, you can make the rotor rotate, with a multimeter to measure the output of the DC is normal.
If it is a brushless DC motor, and the three-phase leads, you can make the rotor rotate, with a multimeter to measure the output alternating voltage is normal.
The output voltage is proportional to the speed.