Correct method for measuring insulation resistance of air curtain cabinet-EEWORLD

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In many cases, if there is a problem with the insulation resistance of the air curtain cabinet compressor, it is easy to cause static electricity in the use of the air curtain cabinet, which poses a certain threat to safety hazards. In this case, we need to measure the insulation resistance of the compressor to prove whether the static electricity is caused by the insulation resistance. Here, Yitongren Refrigerator will show you how to measure it correctly.

　　Therefore, when we use the above method to measure the insulation resistance of the air curtain cabinet compressor, it is best to unplug the power supply of the air curtain cabinet. If the measurement results show poor insulation, Shuangxiong Refrigeration after-sales staff recommends that you replace the compressor with the same model and specification to avoid continued use when a defect occurs.

Now many air curtain cabinets on the market are fully enclosed compressor style, so when we measure the DC resistance value of the motor winding of this fully enclosed compressor, we must also measure the insulation resistance of the compressor motor winding. The correct measurement method is to connect two different types of measuring wires of the megohmmeter for measuring resistance between the lead column and the shell of the compressor. It is best to use a 500V megohmmeter for measurement. The advantage of this meter measurement is that the insulation resistance value should not be less than 2MΩ.

　　If the measured insulation resistance is lower than 2MΩ, it means that there is leakage between the motor winding and the core of the compressor and it cannot be used any more. If there is no such megohmmeter, you can also use the R×10k block of the multimeter resistance block to measure and judge.

　　When measuring, do not let your fingers touch the probe of the multimeter to avoid erroneous readings and affect accuracy. The poor insulation of the air curtain cabinet is basically caused by the following two reasons: one is that the insulation of the wires is rubbed or collided due to careless assembly during assembly or maintenance of the compressor, and the insulation performance of the wires is reduced due to erosion by refrigeration oil and refrigerant; the other is that the insulation layer of the motor winding is damaged, causing a local short circuit between the winding and the core.

Reference address：Correct method for measuring insulation resistance of air curtain cabinet

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