Siemens 3RV1021-0KA15 Motor Starter Protector

Siemens 3RV1021-0KA15 is a Sirius 3RV1 motor starter protector in size S0 that provides integrated overload protection for small AC motors. It features an adjustable overload current range of 0.9 to 1.25 A and a Class 10 thermal-magnetic trip characteristic, delivering reliable protection against motor overload and short-circuit conditions. The device includes a transverse auxiliary contact configuration of 1 normally open (NO) and 1 normally closed (NC), enabling signaling or interlocking within a control circuit. Wiring is via screw terminals, and the unit is designed for DIN-rail mounting in standard control panels, facilitating compact installation with compatible contactors to form a motor starter assembly. The 3RV1021-0KA15 is rated to interrupt fault currents up to 100 kA at 400 V, providing a robust protection profile for compact motor circuits. As part of Siemens' Sirius 3RV1 family, this motor protector combines overload protection with a built-in signaling path, suitable for use in equipment such as conveyors, pumps, fans, and machine tools where space is at a premium and precise motor protection is required.