This　paper　developed　a　set　of　cable　cutting　system　that　can　produce　parallel　metallicity　contact　arc　faultquickly　and　safely.　The　stepper　motor　was　selected　as　the　power　device.　By　setting　the　fine　fraction,　different　wire　diameter　of　cables　can　be　cut　accurately.　And　the　acquisition,　storage　and　analysis　of　the　waveform　of　the　voltage　and　current　can　be　automatically　completed　in　the　moment　of　arcing　period.　The　processes　of　communication　was　made　between　host　computer　and　salve　computer　with　the　basic　functions　of　the　simulation　of　arc　fault　to　achieve　the　integration　of　control　process　of　stepper　motor,　cable　cutting,　arc　discriminant,　waveform　acquisition　and　analysis,　so　as　to　build　up　a　cable　cutting　system　of　which　the　automation　can　be　realized.　By　verification,　the　system　can　produce　arcing　half-cycles　that　meet　the　requirement,　and　it　has　the　characteristics　of　high　automation,　flexible　operation　and　safe　use.