Gas discharge tube (GDT) surge arresters are used to protect circuits and equipment from lightning strikes and static electricity. They are mainly used to set up lightning protection in the circuit to prevent damage due to overvoltage. When overvoltage occurs in the circuit, the GDT will automatically trigger and guide the overvoltage to the atmosphere to relieve the circuit load, thus protecting the safety of the circuit and equipment. However, GDT can only be used to prevent transient overvoltage and cannot prevent long-term overvoltage. Secondly, GDT may sometimes experience gas discharge, so it is necessary to choose the appropriate size and rated voltage to avoid negative impacts on the circuit.