The Siemens 3RB2016-2RB0 is a SIRIUS solid-state overload relay with a CLASS 20E trip curve, designed for contactor mounting on the main current circuit. It provides motor overload and phase-loss protection for three-phase AC motors up to 690 V AC-3 rated maximum. The ATEX certification (PTB 06 ATEX 3001 Ex II (2) GD) permits use in gas and dust hazardous areas where the relay itself is outside the zone but protects motors inside it. Rated for continuous operation from -25 to +60 °C, it handles shock loads up to 15g / 11 ms and carries a surge voltage resistance of 6 kV. The IP20 front face suits enclosed panel mounting; the screw-type main circuit terminals accept 0.5 to 4 mm² (2x 0.5 to 2.5 mm²) solid or stranded conductors.
Mounts directly onto a contactor via the contactor mounting interface — no DIN rail required. The 45 mm width and 64 mm height match the footprint of SIRIUS contactors in the same frame size. Auxiliary contact ratings are provided for multiple control voltages: 2 A at 24 V, 4 A at 120 V, 3 A at 230 V, and lower ratings at 60 V, 110 V, 125 V, and 220 V. The relay can be mounted in any orientation, with side clearance of 6 mm and zero clearance required upwards, forwards, backwards, and downwards.
EMC immunity includes 2 kV burst on power ports and 1 kV on signal ports per IEC 61000-4-4 severity level 3. Pollution degree 3 rated at 690 V, meaning it withstands conductive pollution in industrial environments. Storage and transport temperature range is -40 to +80 °C; relative humidity tolerance is 100 % during operation.