How to use a multimeter to measure the quality of an electric fan motor
1. Use the resistance setting of a multimeter to measure the coil. There is no distinction between red and black pens. The RX1K gear is also okay because there are no signs of burning in the coil. As long as the coil is connected, it will be fine. Use the 1K level to be more sensitive. Connect a test lead to a wire.
2. Use another test lead to measure 3 wires accordingly. There is a wire going through it, which is a set of coils. The remaining 2 wires are another set of coils. The two sets of coils of this exhaust fan are exactly the same, and any set of starting and running windings can be used.
3. Then measure whether the two sets of coils are insulated from each other. As shown in the picture.
4. Then set the multimeter to RX10K to measure the insulation of each winding.
5. The measurement result should be that the two windings and the shell are insulated and the pointer will not move. Be careful not to let your hands touch the metal parts of the two test leads. Because when human hands touch the test leads, there is a resistance of tens of kiloohms. If these two conditions are met, the motor will work normally.
Extended information:
Precautions for using multimeter
1. Before using the multimeter, you should perform "mechanical zero adjustment", that is, when there is no electric quantity being measured, the multimeter pointer should point at the zero voltage or zero current position.
2. When using the multimeter, do not touch the metal part of the test lead with your hands. This can ensure the accuracy of the measurement on the one hand and personal safety on the other hand.
3. When measuring a certain amount of electricity, you cannot change gears while measuring, especially when measuring high voltage or large current, you should pay more attention. Otherwise, the multimeter will be damaged. If you need to change gears, you should disconnect the test leads first, and then measure after changing gears.
4. When using the multimeter, it must be placed horizontally to avoid errors. At the same time, attention should also be paid to avoiding the influence of external magnetic fields on the multimeter.
5. After using the multimeter, the transfer switch should be set to the maximum AC voltage range. If it is not used for a long time, the battery inside the multimeter should also be taken out to prevent the battery from corroding other components in the meter.
