The 3RV2031-4DA10-ZX95: Trip Class 10 means it clears a locked-rotor condition within 10 seconds at 7.2× rated current — standard for most general-purpose motor loads like pumps, fans, and small conveyors. Phase failure detection is built in, so a single-phased motor won't cook before the bimetal catches it. Rated short-circuit breaking capacity at 400 V is 30 kA, dropping to 6 kA at 500 V and 3 kA at 690 V. That 30 kA at 400 V is enough for most industrial panel buswork without needing a current-limiting upstream device.
Mounting and wiring
Snaps onto 35 mm DIN rail per DIN EN 60715 — screw and snap-on both work. Width is 55 mm, depth 149 mm, height 140 mm. Clearance: 50 mm above and below, 10 mm to the side, zero forward or backward. That 55 mm footprint is standard for this frame size; it'll drop into a panel laid out for a 3RV20 series breaker without re-drilling the rail. Main circuit terminals accept 2× (1–25 mm²) or 1× (1–35 mm²) solid or stranded copper. Screw-type terminals, M6 on the main contacts. Torque them properly — loose connections on a motor circuit breaker are a fire risk, not just a nuisance trip.