This instrument can measure AC/DC voltage/current signals of any range given by the user, with optional data retention or peak retention with power-off memory function, and true effective value measurementVoltage/current/power/power factor/frequency/kWh/reactive power, etc., with three sets of alarm outputs, can be used in power systems, factory distribution, building automation, etcAutomatic control of distribution electrical engineering, equipped with RS485 communication, can be remotely connected to a computer.