What this SENTRON switch disconnector does
The Siemens 3NJ6313-3AC0.-.... is a 3-pole switch disconnector with fuses from the SENTRON 3NJ63 family, designed for in-line mounting. It takes NH1 fuse links rated up to 250 A and handles motor switching duty at AC23A 500 V. A manual operating mechanism and EFM 20 electronic fuse monitoring are built in. The fuse monitoring gives you a remote signal when a link blows, so a lube route or a conveyor line doesn't run single-phased until the next walk-through.
The AC23A rating at 500 V is the motor-switching duty class — it tells you this disconnector can make and break motor loads, not just resistive heaters. The NH1 fuse size is standard across the SENTRON line, so replacement links are widely available. It's a 3-pole in-line design — mounts on a panel backplate or in an enclosure, not a DIN rail. The EFM 20 monitoring module connects to your control voltage for the blown-fuse signal; wire it to a PLC input or an alarm lamp. Group code P360 and product group 5862 are Siemens internal classifications for ordering and catalog cross-reference.