Just yesterday I saw a piece of news saying that there was an electric shock on the meter of a family in the countryside, and there were casualties. I thought about it. This meter must have not been handled properly, otherwise, the industry knows about safety capacitors. This thing is divided into X capacitors and Y capacitors. X and Y capacitors are safety capacitors, the X capacitor between the live wire and the neutral line, and the Y capacitor between the live wire and the ground. The two and three poles are used in the power filter to filter the power supply, respectively, for common mode, Differential mode interference is used to filter. Safety capacitors are used in such occasions, that is, after failure, they will not cause electric shock and do not endanger personal safety. The peak pulse voltage and overvoltage levels allowed in the safety level of safety capacitors (IEC664 ) X1 >2.5kV ≤4.0kV Ⅲ X2 ≤2.5kV Ⅱ X3 ≤1.2kV-safety capacitor safety grade insulation type rated voltage range Y1 double insulation or reinforced insulation ≥ 250V Y2 basic insulation or additional insulation ≥ 150V ≤ 250V Y3 basic Insulation or additional insulation ≥150V ≤250V Y4 Basic insulation or additional insulation <150V The capacitance of Y capacitors must be limited, so as to control the leakage current flowing through it under the action of rated frequency and rated voltage and the EMC performance of the system The purpose of the impact. For diodes, GJB151 stipulates that the capacity of Y capacitors should not be greater than 0.1uF. In addition to complying with the corresponding grid voltage withstand voltage, Y capacitors are also required to have sufficient safety margins in terms of electrical and mechanical properties to avoid breakdown and short-circuit under extremely harsh environmental conditions. Protecting personal safety is of great significance!

        The installation of safety capacitors not only protects the equipment but also protects the people, and the price is not very high. With a small amount of money, you can rest assured, why not do it?