Abstract: Ground fault is one of the main causes of electrical fire, and it is also a difficult issue in fire investigations. By building a low-voltage ground fault test platform, this paper studied the ignition characteristics of two different types of ground faults, as well as the temperature rise characteristics of the wire insulation layer and fault contact point under different ground fault currents, and analyzed the action characteristics of the air switch, the ignition characteristics of combustibles and the trace characteristics of the ground fault under different types of ground faults. The research results can provide technical support for the investigation of ground fault electrical fires.

Key words: ground fault, ignition characteristics, trace characteristics, electrical fire investigation