What is the meaning of dj displayed by the red-phase electric energy meter?

The dj displayed by the red-phase watt-hour meter is a DC watt-hour meter. According to relevant public information, DJ stands for DC ammeter, which is designed for DC screen, solar power supply, telecom base station, subway and other applications. This series of instruments can measure voltage, current, power, forward and reverse electric energy in DC system. Xiamen Hongxiang Electric Power Equipment Co., Ltd., a well-known (famous) electric meter brand, a famous trademark in Fujian Province, a high-tech enterprise in Fujian Province, a member of China Instrument Industry Association, and a leader in the field of electrical equipment condition maintenance in China, is a company specializing in the research and innovation of electrical equipment condition detection and monitoring products and electric energy meter technology.