2. The lightning arrester is connected between the cable and the earth, usually in parallel with the protected equipment. Lightning arresters can effectively protect communication equipment. Once abnormal voltage occurs, the arrester will act to protect. When communication cables or equipment are operating at normal operating voltage, the lightning arrester will not work and is considered an open circuit to the ground. Once high voltage occurs and threatens the insulation of the protected equipment, the arrester will act immediately and direct the high voltage surge current to the earth, thereby limiting the voltage amplitude and protecting the insulation of communication cables and equipment. When the overvoltage disappears, the arrester quickly returns to its original state, allowing the communication line to operate normally.
3. The characteristics of a good arrester are: large flow capacity, excellent protection characteristics, good sealing performance, good pollution removal performance, high operational reliability, and strong power frequency tolerance. This is also used to detect the quality of lightning arresters.
