What this part is and its key ratings
The 3RV2021-4NA10: The breaker measures 45 mm wide by 97 mm deep by 97 mm tall, mounting on a 35 mm DIN rail per DIN EN 60715 via screw and snap-on. This is a standard footprint for a 45 mm motor-protective device, leaving a 50 mm clearance above and below, and 30 mm on the sides. Main terminals accept up to 2x 10 mm² solid or stranded, using M4 screws. Ambient operating range is -20 to +60 °C; storage and transport range is -50 to +80 °C. The part operates at rated voltages from 20 to 690 V.
Mounting and integration
Snap-on mounting onto 35 mm DIN rail (DIN EN 60715) is standard; screw fixing also allowed. Any orientation is permissible. Clearance: 50 mm above and below, 30 mm sides, 0 mm forward and backward — so panel layout needs space only for height and width, not depth behind the rail. Phase failure detection is built in; ground fault detection is not. The trip current is adjustable (rated value range not specified in evidence, but the unit is a motor-protective breaker with Class 10). For a standard 3-phase motor circuit, this breaker sits ahead of the contactor and overload relay, providing short-circuit and overload protection in one device.