Weather　the　arc　is　separated　by　the　deion　plates　or　not　will　determine　success　or　failure　of　interruption　for　current-limiting　circuit　breaker.　So　it＇s　important　to　investigate　the　separating　condition　of　arc　by　the　splitters.　In　this　study　the　oscillating　circuit　is　used　as　supply　power.　For　circuit　breaker　with　250A　frame　size,　different　materials　and　numbers　of　splitters　are　tested　in　short　current　interrupting　process.　Experiment　results　verified　the　necessary　condition　of　successful　arc　separating　process.　While　the　arc　column　voltage　is　higher　than　total　voltage　of　separated　arc,　the　arc　will　be　possibly　separated.　With　the　increase　of　splitters　number　the　required　current　is　higher　while　the　other　parameters　are　constant.　Larger　number　of　splitters　means　higher　corresponding　arc　voltage,　which　may　more　easily　cause　back　strike.