The Siemens 3RB2056-2FF2 is a SIRIUS solid-state overload relay — an electronic, not bimetallic, overload protection device for three-phase AC motors. It's sized for the S6 frame, which means it mates physically with S6 contactors in the SIRIUS family for a coordinated motor starter assembly, or can be mounted standalone. Rated operational current is 200 A with CLASS 20E trip class. Rated insulation voltage is 1,000 V, and the maximum operational current at both 480 V and 600 V is 200 A — so the 200 A rating holds across common industrial voltage levels without derating. The thermal current (Ith) is also 200 A, confirming the continuous current path is rated for that full value. For motor sizing: at 500 V / 50 Hz, this relay covers motors from 30 kW up to 132 kW. That's a wide power band for a single frame size, made possible by the electronic overload release (no heater elements to swap).
Mounting, wiring, and environment — what fits where
Mounts directly on a SIRIUS S6 contactor (e.g., 3RT5056) or as a standalone unit via the base. Fastening method is contactor mounting or stand-alone installation. Main circuit connection is via busbar connection (M8 bolts for the main contacts). Auxiliary/control wiring accepts 2× (0.25... 1.5 mm²) solid or stranded wire — typical for signal-level connections. The auxiliary switch is integrated, not an add-on module. Storage and transport range is -40 to +80 °C. Vibration resistance: 1-6 Hz at 15 mm amplitude, 6-500 Hz at 20 m/s², 10 cycles. Shock: 15g / 11 ms per IEC 60068-2-27.
Auxiliary contact ratings — the control side
The integrated auxiliary switch has these contact ratings: 2 A at 24 V, 0.55 A at 60 V, 0.3 A at 110 V, 4 A at 120 V, 0.3 A at 125 V, 0.11 A at 220 V, and 3 A at 230 V. The lower DC ratings (0.55 A at 60 V, 0.3 A at 125 V) reflect DC arc interruption limits.
RoHS compliance date is noted as July 1, 2006 — compliant with the original RoHS directive. No conflict minerals or REACH SVHC flags are in the evidence; standard EU industrial compliance applies.