ASL-410 series digital line protection and monitoring device including ASL-411 (two-component) and ASL-412 (three components), two models, applicable to 66kV and below voltage small current grounding system, or with current and voltage protection 110kV The line is a line unit of the spacer layer device. Main functions: a) three-stage low-voltage blocking direction with overcurrent protection: the atresia or direction of each piece of low-voltage lockout can be individually cast back; b) a three-phase auto-reclose function; c) frequency load shedding: Low-voltage lockout and current atresia can be cast back, selectable frequency load shedding export trip or alarm; d) small current grounding line; e) zero-sequence current protection function: export trip or alarm selectable; f) event logging, fault recorder. Note: In addition to these basic functions, ASL-412 increase ratio ASL-411 the reclosing check the same period / inspection no pressure function.