Panel fit and motor load matching
The 3RA6250-1DB33 is a SIRIUS compact reversing starter — a single device combining a contactor, overload relay, and reversing interlock for bidirectional motor control. At 400 V it handles 5.5 kW motor loads, while at 480 V and 600 V the rated current is 12 A, covering common North American voltage tiers. The adjustable trip class 10/20 lets you match the overload curve to the motor start profile: class 10 for fast-starting pumps and fans, class 20 for high-inertia loads like conveyors or crushers. Dimensions are 170 mm high, 90 mm wide, and 165 mm deep — the 90 mm width occupies three 18 mm DIN-rail modules, which matters when laying out a dense panel with multiple starters.
Environmental and mechanical ruggedness
Rated for continuous operation per IEC 60947-6-2 and pollution degree 3 — this is the standard for industrial enclosures where conductive dust or condensation is present. Shock resistance is 60 m/s² (6g) for 10 ms, three shocks per axis, and vibration resistance covers 4–5.8 Hz at 15 mm amplitude, then 5.8–500 Hz at 20 m/s² for 10 cycles. That means it holds up on machine-mounted panels near presses, conveyors, or crushers without nuisance trips or contact bounce.
Termination and wiring
The main circuit terminates via plug-in connections without terminals — the starter ships with the contactor and overload pre-assembled, and the load-side wiring goes into the plug-in base. Three LEDs indicate status — typically power on, overload trip, and fault — which helps during commissioning and fault-finding without needing a multimeter on the terminals.