Electrostatic discharge (ESD) and electrical fast transient pulse group (EFT) will cause varying degrees of harm to instrumentation systems. Electrostatic discharge produces strong radio frequency radiation in the frequency range of 5 to 200 MHz. The peak of this radiated energy often occurs between 35MHz and 45MHz, and self-oscillation occurs. The resonant frequency of many information transmission cables is usually in this frequency range, resulting in a large amount of electrostatic discharge radiation energy in the cable. Electrical fast transient bursts also generate quite strong radiation emission, which couples to cables and chassis lines. When the cable is exposed to 4 ~ 8Kv electrostatic discharge environment, the induced voltage that can be measured on the terminal load of information transmission cable can reach 600V, which far exceeds the threshold voltage of typical digital instruments by 0.4V, and the typical induced pulse duration is about 400 nanoseconds.

  Instruments and meters often encounter unexpected voltage transients and surges in use, resulting in damage to electronic equipment. The damage is due to the burning or breakdown of semiconductor devices (including diodes, transistors, thyristors and integrated circuits) in instruments and meters. According to statistics, 75% of the failures of instrumentation are caused by transients and surges. Voltage transients and surges are everywhere. Power grids, lightning strikes, explosions, and even people walking on the carpet will produce tens of thousands of volts of electrostatic induction voltage. These are invisible and deadly killers of instruments and meters. Therefore, in order to improve the reliability of instruments and the safety of human body, protective measures must be taken against voltage transients and surges. Jinli signal spd escorts the safe use of instruments and meters.