... voltmeter,ammter,power meter.... SpecificationsDDS6789 single phase acive electronic energy meter meet IEC61036:2000 standard, DIN-RAIL ... technique, and imported large scale integrate circuit, use advanced technique of digital and SMT techniques, etc ... Extension terminals cover, in order to protect to use safety. Technical parameters ModelAccuracyReferencevoltage (V)Currentspecifications (A) ...