The DD862 type single-phase watt-hour meter is a kind of induction type meter,which is applicable to measure the rated frequency 50Hz and power loss in electrified-wire netting. The meter has novel design, rational structure and features of high over-load, low power loss and long life etc. All technical targets are completely conformed to the stipulated requirement of National Standard GB/Tl7215 311 -2008 Class 0 5,1 and 2A.C Active Watt-hour Meter and International Standard IEC60521.