What this reversing compact starter does
The Siemens 3RA6250-2AB34 is a SIRIUS reversing compact starter — a single device that combines a reversing contactor pair, overload relay, and short-circuit protection coordination into one 90 mm wide package. Rated for continuous operation per IEC 60947-6-2, it handles motor reversing without external interlocking wiring. The adjustable trip class (CLASS 10 and 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 that need a longer acceleration ramp.
Mounting and wiring in the panel
The 90 x 191 x 165 mm footprint fits a standard motor-starter slot in a SIRIUS lineup. Main power connections use spring-loaded terminals (2x 0.25 to 1.5 mm² solid or stranded) — no screw torque to verify, just strip to 8 mm and push. The 24 V AC/DC coil draws 2.8 W AC maximum or 2.9 W DC maximum, so a standard 24 VDC power supply handles it without derating.
Built for the nacelle — shock and vibration
Rated for 60 m/s² (6g) shock over 10 ms, three shocks per axis, and vibration tested to 5.8 Hz at 15 mm amplitude then 20 m/s² up to 500 Hz. This is the kind of spec that matters up-tower: no loose connections or relay chatter from blade-pitch transients or gearbox harmonics. Operating temperature range of -20 to +60 °C covers most unheated nacelle environments; storage and transport range of -55 to +80 °C covers cold-chain and desert shipping.