Siemens 3RV2021-4BA10 Soft Starter

Siemens 3RV2021-4BA10 is a SIRIUS 3RV2 motor protection switch (S0 size) that provides integrated motor overload and short-circuit protection for 3‑phase motors in control panels. It operates on 220–690 V AC and is designed for DIN rail mounting with screw-terminal connections for reliable field wiring. The device offers an adjustable overload (A‑release) current of 13–20 A and a short-circuit (N‑release) up to 260 A, delivering standard switching capacity suitable for common motor protection tasks. Rated to handle motor loads up to approximately 7.5 kW, this 3RV2 module is part of Siemens' Sirius protection family and is commonly used in new builds or retrofits where compact, modular motor protection is required. It is also marketed as a replacement for the older 3RV1021-4BA10, enabling a straightforward swap in compatible installations.