Watt-hour Meter 1.Single Phase 2.Rated voltage:220V 3.Rated current:2,3,5,10,20,30,40 DD28 Type Single Phase Watt-hour MeterThis meter is king of induction meter ,which is appli.cable to measure the rater frequency 50Hz and power loss in electrified wire netting. All technical targets are completely conformed to National Standard GB/T15283-94 and international StandardIEC521.