... energy and active energy with multi-tariff watt-hour meters, kwh meters, meter DTSD450 and DSSD450 series three-phase electronic multi ... and standard DL/T 645-1997 Multi-function Watt-hour Meters Communication Protocol as well as total technical requirements for ... three-phase electronic multi-function watt-hour meters stipulated in standard GB/T 17215-2002/IEC 61036. ...