How to measure the starting capacitor of air conditioner compressor

The air conditioner compressor is very important to the air conditioner. If there is a problem with the starting capacitor of the air conditioner compressor, the air conditioner will not work normally. If there is a problem with the starting capacitor,we can't find the master to come to repair for a while, we need to manually replace the starting capacitor by ourselves, so it is very important to master the replacement method of the starting capacitor of the air conditioner compressor.Generally speaking, air conditioners are divided into single-phase electricity and three-phase electricity. Single-phase electricity has three capacitors, namely, the internal fan capacitor, the external fan capacitor and the compressor capacitor; while the three-phase compressor does not use capacitors, so there are only two capacitors, that is, the internal fan capacitor and the external fan capacitor.

Air conditioner capacitors work in ac circuits, so they are all non-polar capacitors. The so-called eight-pin capacitor mentioned in the title should be the one on the left of the picture below.Although there are many pins, they are only concentrated on two points. The eight pins are only for the convenience of wiring. In fact, it is a two-pin capacitor.The nine legs of the capacitor on the right are concentrated at three points, which means that two capacitors are packaged together, one of which is a common leg. Therefore, before measuring, it is necessary to find out how many capacitors are installed inside.

There is no difference between the measurement method of capacitance and ordinary capacitance. It can be measured with a digital multimeter or a pointer multimeter.

To measure with a digital meter, you can turn the meter to the capacitance position as shown in the figure above, select a position slightly larger than the nominal value of the capacitance, and read the capacity directly from the display.Air conditioners do not have very strict requirements on the capacity of capacitors. It can be used if it is less than ±10%, but if it is less than 10%, replace it, because the capacitor may have failed.

Capacitance can also be measured with the ohm range of a pointer multimeter. The advantage of the pointer multimeter is that the Rx10K file can be used to measure the leakage. Because the voltage of the battery in the meter is relatively high, the measurement result is close to reality, and generally should not be lower than several hundred megohms.The disadvantage of the pointer multimeter is that the measured capacity is not very accurate, but you can use a low withstand voltage capacitor with a relatively accurate capacity for comparison, and adjust the gear to make the pointer swing near the middle of the dial for easy observation and comparison.

Generally, the starting capacitor of the compressor is mostly used around 80μF.Whether it is a mechanical watch or a digital watch, use the resistance files K-level and 100-level to measure respectively. After the red and black test pens are measured once, quickly exchange the pen sticks and measure again, and repeat this several times.

1. No value. Measure a good capacitor to verify the multimeter, if the meter is normal, the capacitor is damaged.

2. The swing or value is small, and the charging and discharging time is very short. You can measure the capacity of an ordinary close to verify the value. Visibly reduced size is damaged and distorted.

3. The values are normal, but the compressor does not start. It is necessary to verify that the compressor is good, and if it does not start or starts occasionally, it is an open circuit of the contact point.

The quality of the capacitor needs to be judged according to the fault phenomenon of the air conditioner, whether it is powered on, whether there is a stall current sound, etc., whether the efficiency drops during normal use in the final stage,multiple startups, and the system reports errors and other abnormal reactions.