The Siemens 3RA6500-2BB42 is a SIRIUS compact reversing starter — a single device that combines two contactors and a motor-protective function in one 191 x 90 x 165 mm package for reversing a three-phase motor. It is designed for continuous operation per IEC 60947-6-2, which means it handles sustained motor duty without derating for the reversing cycle. The trip class is adjustable between CLASS 10 and CLASS 20, so you set the overload response to match the motor's starting profile — CLASS 10 for fast-starting loads like pumps, CLASS 20 for higher-inertia loads like conveyors.
This reversing starter includes IO-Link at COM2 (38.4 kBaud), giving the PLC direct access to the starter's status, current draw, trip history, and parameter settings over a standard M12 connection. Five onboard LEDs provide local diagnostics — useful during commissioning or when a line-down event needs a quick visual check. The IO-Link protocol means you can reconfigure the trip class, reset faults, and read the load current without opening the panel door, which cuts troubleshooting time on multi-starter cabinets.
Ratings that govern fit and protection
That is the SCCR the panel label needs to match. The 1.25 A at 480 V and 0.5 hp at 460/480 V define the motor full-load current it can switch continuously in reversing duty. The 2.9 W DC coil hold power keeps the heat load low in a densely packed DIN-rail enclosure.
Mounting and wiring in the panel
Mounts vertically on a standard DIN rail with screw and snap-on fastening — no tools needed for removal. Vibration resistance is specified at 4 to 5.8 Hz with 15 mm displacement and 5.8 to 500 Hz at 20 m/s² for 10 cycles, so it holds up on a machine frame or conveyor line.