Design of new AC/DC current meter

The system uses AT89C51 series single-chip microcomputer as the control unit.This paper introduces a novel current test method which adopts ACS712Holzer current measurement chip as the measurement tool,with a measurement range of 0-5A.The system has the advantages of novel structure,simple circuit,accurate test,low production cost and small volume,etc.,thus it is particularly suitable for high precision AC or DC current test in various fields such as the industrial,commercial and communication systems.