... 60Hz, DT862, DT864, DS862 and DS864 series are the three-phase active energy watt -hour meters, and DX862, DX864, DX865 and DX863 series are ... , reference frequencyand COS =1 (reactive energy watt-hour meter sin =1),when the load current can't exceed the starting currentin the ... table, the rotary disc of watt-hour meter canstart and ...