The Siemens 3RV6021-4EA10 is a SIRIUS motor-protection circuit breaker, size S0, with a 32 A rated operational current and Trip Class 10. It combines a thermal overload release and a magnetic short-circuit trip in one 3-pole package, so it protects the motor feeder from both sustained overload and fault currents without needing a separate overload relay. That makes it a direct fit for conveyor drives, pumps, and compressors where the motor starts under load.
The 45 mm width and 96 mm depth mean it occupies one standard modular unit on the rail — no surprises when laying out a row of motor starters. Any mounting position works.
Wiring and connections
Screw-type terminals on top and bottom accept 2×(1–2.5 mm²) solid or stranded, or 2×(2.5–10 mm²). For AWG: 2×(16–12) or 2×(14–8). Torque to 2–2.5 N·m. The terminals are arranged top and bottom, which keeps the wiring straight in a panel — no looping around the side.
Electrical ratings and environment
Rated insulation voltage 690 V, AC-3 switching at 400 V at the full 32 A. Operating frequency 50/60 Hz, and it can handle up to 15 switching operations per hour at AC-3. Surge voltage withstand is 6 kV. Humidity 10–95% non-condensing. Shock rated 25g / 11 ms per IEC 60068-2-27. Installation altitude up to 2000 m. The breaker is rated for short-circuit protection (integral magnetic trip), so it can clear faults without relying on an upstream fuse for motor branch circuits.