Motor protection circuit breaker for dusty environments
The Siemens SIRIUS 3RV1011-0KA10-ZW98 is a motor protection circuit breaker designed for the grit and heat of industrial floors — kiln rooms, crusher panels, mill MCCs. Rated Trip Class 10, it disconnects a stalled motor fast enough to keep windings intact, which matters when a conveyor jams and the line can't wait for a thermal overload to cool down. Phase failure detection is built in, so a dropped leg on a 400 V feeder won't cook the motor while the breaker sits there reading the remaining two phases. Breaking capacity hits 100 kA at 400 V — that's fault-current capability that handles the stiffest distribution transformers without cascading upstream.
Mounting and wiring in a tight panel
Snaps onto 35 mm DIN rail per DIN EN 60715, or screws direct to a backplate. The 45 mm width keeps the fill factor tight — you can pack a dozen of these across a 600 mm rail for a multi-motor group. Screw terminals on the main circuit accept 2x (0.5 to 1.5 mm²) solid or stranded, or 2x (0.75 to 2.5 mm²) — no ferrule crimping required for the smaller wire. Mounting position is any, so vertical or horizontal rail orientation works. Clearance: 20 mm above and below, 9 mm to the side, zero forward or backward. That 75 mm depth leaves room for wiring ducts behind a 200 mm deep enclosure.
Thermal environment and operating limits
Runs from -20 to +60 °C during operation — that covers a control room next to a preheater tower or a summer-afternoon MCC in a cement plant. Storage and transport range is -50 to +80 °C, so it survives a hot shipping container or a frozen warehouse. The rated operating voltage spans 20 to 690 V, which means it works on 240 V single-phase control transformers as well as 400 V three-phase motor feeds. For fuse backup: at 400 V use gL/gG 20 A; at 690 V step down to gL/gG 16 A. No fuse required at 240 V.