How to measure the quality of a 220V motor with a multimeter
1. Measure the coil using the resistance range of a multimeter. As long as the coil is on, it's better to use 1K gear for sensitivity. Connect one pen to another wire.
2. Use the other pen to measure 3 lines accordingly.
3. Measure whether the two sets of coils are insulated from each other. As shown in the figure.
4. Next, turn the multimeter to the RX10K range to measure the insulation of each winding.
5. The result of the measurement should be that the two windings and casing are insulated and the pointer will not move.
Extended Information:
In general, a multimeter can be used to determine whether the motor is burned or not. Before measuring, the connecting pieces of the three-phase motor should be removed, and then the ohm range of the multimeter should be used to measure whether the three windings are short circuited. The highest resistance range of the multimeter can be used.
If there is no resistance value in the measurement, it is basically determined that there is no phase to phase short circuit in the three-phase winding. Then, measure each phase of the three-phase winding to the ground separately. If there is no resistance value, it is determined that the motor is not grounded. Then, measure the resistance values of the three windings. Regardless of the size of the motor, if the resistance error of the three windings measured is very small, it can be determined that the motor is not faulty.
If there is an open circuit or significant resistance error in one or both phases, it can be determined that the motor is burned. If there is still suspicion, the end cover can be removed for further confirmation.
Ohm Ω range is used to measure the impedance of the coil, and the resistance value is generally not large. 10k range is used to measure the leakage of the shell. The smaller the resistance value, the greater the leakage. It is better to use a megger to measure. Do not touch the metal parts when measuring, as the human body may affect the measurement accuracy. It is difficult to measure the inter turn short circuit of the coil.
