The Siemens 3RA6400-1DB42 is a SIRIUS compact starter designed as a direct starter for IO-Link communication. The adjustable trip class (CLASS 10 and 20) lets you match the thermal protection to the motor start profile — CLASS 10 for faster starts, CLASS 20 for higher-inertia loads like fans or conveyors. Rated at 12 A at 400 V AC (AC-3 motor switching duty), it handles motors up to 5.5 kW at 400 V, 7.5 hp at 460/480 V, and 10 hp at 575/600 V. The screw-type terminals on the main circuit accept 0.5 to 4 mm² solid or stranded wire, or two conductors 0.5 to 2.5 mm² each.
IO-Link integration and configuration
This compact starter supports IO-Link protocol at COM2 rate (38.4 kBaud), making it addressable from any IO-Link master for parameterization, diagnostics, and status monitoring. The three onboard LEDs provide local indication of device state, overload, and communication status. The IO-Link profile allows remote adjustment of the trip class, current setting, and restart behavior without opening the panel — useful for machine builders who want to standardize on one starter variant and configure it per motor at commissioning.
It withstands shock at 60 m/s² (6 g) for 10 ms across three shocks in all axes, and vibration per 10 cycles at 4 to 5.8 Hz with 15 mm amplitude and 5.8 to 500 Hz at 20 m/s². The no-load switching frequency is rated at 3600 operations per hour.