There are many kinds of arresters, including metal oxide arresters, line-type metal oxide arresters, gapless line-type metal oxide arresters, fully insulated composite jacketed metal oxide arresters, and detachable arresters.
The main types of arresters are tubular arresters, valve arresters and zinc oxide arresters. The main working principle of each type of arrester is different, but their work is essentially the same, all to protect communication cables and communication equipment from damage.
Tubular arrester
The tubular arrester is actually a protection gap with high arc extinguishing ability. It consists of two series gaps. One gap is in the atmosphere, which is called the outer gap. Its task is to isolate the working voltage and prevent the gas production tube from flowing through the tube. The other is installed in the gas pipe, which is called the inner gap or arc extinguishing gap. The arc extinguishing ability of the tubular arrester is related to the size of the power frequency freewheeling. This is a protective gap type arrester, which is mostly used for lightning protection on power supply lines.
Valve arrester
The valve arrester is composed of spark gap and valve plate resistance. The material of valve plate resistance is special silicon carbide. The valve plate resistor made of silicon carbide can effectively prevent lightning and high voltage, and protect the equipment. When there is a high voltage of lightning, the spark gap is broken down, the resistance value of the valve plate resistor drops, and the lightning current is introduced into the ground, which protects the cable or electrical equipment from the damage of the lightning current. Under normal circumstances, the spark gap will not be broken down, and the resistance value of the valve plate resistor is high, which will not affect the normal communication of the communication line.
Zinc oxide arrester
Zinc oxide arrester is a lightning arrester with superior protection performance, light weight, pollution resistance and stable performance. It mainly uses the good nonlinear volt-ampere characteristics of zinc oxide, so that the current flowing through the arrester is extremely small (micro-amp or milli-amp level) under normal working voltage; when over-voltage acts, the resistance drops sharply, discharging the over-voltage energy for protection. The difference between this arrester and the traditional arrester is that it has no discharge gap, and uses the nonlinear characteristics of zinc oxide to play the role of leakage and interruption.
Several arresters have been introduced above. Each arrester has its own advantages and characteristics. It needs to be used in different environments to achieve a good lightning protection effect.
