The HND-T series protection and measurement device consists of line protection, transformer protection, capacitor protection, motor protection, PT parallel device, and automatic switching device for backup power supply. It can meet the requirements for ensuring the safe operation and reliability of power energy in power systems with voltage levels of 66kV and below. Currently widely used in automation systems such as power plants, substations, industrial and mining enterprises, hospitals, schools, commercial plazas, and large buildings.