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At present, various countries have clear instructions on the specifications of power cords, and my country also has relatively strict specifications. If the specifications are not met, the power cord cannot be allowed to circulate in the market. This prompted the birth of the national standard power cord, so what are the measurement standards for the national standard power cord?

　　 Criterion 1: Appearance

　　 The national standard power cord has clear regulations on the appearance and packaging of the wire. The power cord that meets the national standard must be clearly written in the certification mark, manufacturer, wire diameter and other product descriptions. At present, most of the popular power cords on the market do not meet the appearance requirements, either without a manufacturer or without a certification mark. Once these external instructions are missing, it means that it is not a national standard wire.

　　 Standard 2: Mechanical strength

　　The mechanical strength of the general national standard power cord must be high. Because the national standard power cord is used in a very wide range, some ranges require relatively high mechanical strength. If it cannot be reached, it cannot be used. In this way, relatively strong mechanical strength must be used to make it more widely used.

　　 Standard 3: Sheath insulation

　　 The insulation performance of the national standard power cord is also relatively high. Generally, the insulation of the sheath is generally greater than 100MΩ, and the withstand voltage must be below 1500V.

　　 Standard 4: Line resistance

　　 Generally, the resistance of the power cord that meets the national standard has strict standards for wire diameter, conductivity and resistance. If these three aspects are not met, it means that the power cord cannot be used as the national standard, otherwise it will bring more trouble to the user.

　　 Standard Five: High and low temperature resistance

　　Because the power cords are used in different environments, they all have the same characteristics, that is, they must have good high and low temperature resistance. Generally, the power cord can be impacted below 159 degrees at high temperature, and there is no cracking in low temperature below minus three or four degrees Celsius, so the power cord can meet the national standard.

　　 As long as these five-point standards are met, then the power cord is in compliance with the national standard.

Article from: http://www.elejintao.com/newsd-nid-64.html