Product introduction AN8721PV3 series AC and DC power meter (hereinafter referred to as instrument) with STM32 controller as the core, using direct sampling and intelligent identification technology, widely used in single-phase electric equipment of voltage and current, power, power factor, frequency, energy, time and other electrical parameters measurement, wide measurement range, the the 4 window LED display button is simple and fast, and has the U disk read and write, serial communication, parameter alarm, voltage / current ratio setting function, has the characteristics of a machine, precise and durable.