The Siemens 3RV2021-0BA10-0DA0 is a SIRIUS 3RV2 motor starter protector in size S0, designed for system protection without phase failure protection. Its A-release (overload) is set for 0.14...0.2 A, and the short-circuit release trips at 2.6 A. It uses screw terminals and offers standard switching capacity.
The 0.14...0.2 A overload range means this protector is sized for very small motor loads — fractional-horsepower pumps, small fans, or control transformers drawing under 0.2 A full-load. The 2.6 A short-circuit release provides magnetic trip for fault currents, coordinating with upstream branch protection. Size S0 is the compact frame in the SIRIUS family, fitting standard DIN-rail mounting in control panels.
Screw terminals accept copper conductors; torque to the specified value on the device label. The compact footprint (101 x 52 x 104 mm) leaves room for adjacent contactors or auxiliary blocks in a motor control center row.