AS-Interface motor starter with integrated brake control
The 3RK4320-3EQ54-0BA3: This SIRIUS motor starter (MCU) is a direct starter designed for AS-Interface bus communication, meaning it drops into a networked automation cell without a separate fieldbus gateway — the AS-Interface protocol is supported natively. The unit includes a motor brake output (400 V AC) and two digital inputs, which saves a separate contactor and terminal block when the application needs a brake release sequence.
Mounting and environmental fit
Dimensions are 245 mm wide by 215 mm tall by 205 mm deep — this is a compact block for a motor starter with integrated bus and brake, but confirm the DIN rail space against the panel layout before routing the AS-Interface cable. Rated IP54, so it handles dust and splashing water in a control cabinet or a dry machine-mount enclosure; not for washdown zones but fine for most factory-floor cabinets.
Control supply and motor protection
Motor protection is bimetallic (thermal overload), with short-circuit protection via circuit-breakers — no separate overload relay needed in the line. Rated for 80 operating cycles per hour minimum (1/h), so it handles frequent start-stop duty on small conveyors or indexing tables without overheating the bimetal.