What it is and what it does
The Siemens 3RV1021-1DA10-0FJ0-ZX95 is a SIRIUS motor protection circuit breaker, rated 3.2 A continuous current with a CLASS 10 trip characteristic, designed for motor loads up to 1.1 kW at 400 V. It interrupts fault currents up to 100 kA at 400 V AC — that SCCR covers most industrial panel bus faults without cascading upstream. Phase failure detection is built in, so a lost leg won't let the motor single-phase to failure.
Mounting and wiring
Snaps onto 35 mm DIN rail per EN 50022, or screws direct to a backplate. 45 mm wide on the rail — two of these fit in the space of a standard three-module MCB. Screw terminals accept solid or stranded wire: 2x (1…2.5 mm²) or 2x (2.5…6 mm²) per clamp. Stripped length and torque as per the terminal marking — no spring-clip surprises. Depth is 96 mm, height 97 mm. Clearances: 0 mm backwards, 0 mm at the sides — can pack it tight against the enclosure wall or adjacent devices.
Environment and endurance
Runs from -20 to +60 °C operating ambient; stores and ships from -50 to +80 °C. Good for unheated warehouses and truck beds. Shock rated at 25 g for 11 ms — survives the ride in a mobile or vibrating machine panel. Front face is IP20; mount it inside a panel anyway. Main contacts rated for 100 000 electrical operations typical at rated load — no wear concern in normal cycling.