Reversing starter with AS-Interface, IP65, 9 A AC-3
The Siemens 3RK1323-5CS44-3AA0 is a reversing starter designed for motor control in distributed automation architectures. It carries a 9 A rated operational current in AC-3 duty at 400 V, meaning it directly switches a 3-phase induction motor up to that current — roughly 4 kW at 400 V — in forward/reverse applications. Supply is 24 V DC nominal, with a rated range of 20.4 to 28.8 V DC and an absolute maximum of 31.6 V DC. The operating voltage for the motor circuit is 400 to 500 V AC. The enclosure is rated IP65, so the unit is suitable for washdown environments or outdoor installation in a cabinet — no additional enclosure needed for dust or hose-directed water.
AS-Interface communication and I/O
This reversing starter communicates via AS-Interface (AS-i) shaped cables using the cutting/clamping method for both data transmission and supply voltage. It has 4 digital inputs, each terminated via M12 sockets, and 2 of those inputs are dedicated to digital input signals. There are no digital outputs on this variant. The inputs are parameterizable. Device addressing is done via a front addressing socket. The main energy infeed and load-side outgoing feeder use sockets per ISO 23570. This standardized connector interface means the unit mates with pre-wired harnesses or distribution boxes that follow that standard — no custom cabling for the power path.
Motor protection and switching
Motor protection is solid-state, so the overload curve is electronic rather than bimetallic — no thermal memory drift, and the trip class is typically adjustable via parameterization. The switching contact is mechanical, meaning the power path uses a conventional electromechanical contactor, not a semiconductor output. The minimum operating frequency is 1 cycle per hour, which is a design constraint for applications requiring infrequent reversals.