The Siemens 3RK1322-1ES02-1AA0 is a reversing starter — an electromechanical motor starter that combines a contactor, overload relay, and reversing function in a single IP65-rated enclosure. It's designed to start, stop, and reverse three-phase motors in applications where space is tight and the environment demands washdown or dust protection. The bimetal overload relay provides motor protection against sustained overcurrent. It communicates over AS-Interface (AS-i), the flat-cable fieldbus common in distributed I/O and motor control centers. Power and data share the same yellow AS-i cable, which simplifies wiring in a multi-drop topology. No PROFIBUS or PROFINET onboard — this is strictly an AS-i node.
AC-3 covers starting and plugging of squirrel-cage motors — the inrush is higher than the running current, and this contactor is sized for that duty cycle. If your motor nameplate exceeds 4 A FLA at 400 V, step up to the next frame. It's suitable for washdown environments, not submersion. Two digital inputs are built in, each via an M12 socket. They are not parameterizable — they're fixed-function inputs for start/stop or limit-switch signals. No digital outputs on this variant.
Integration notes
The enclosure measures 190 mm deep, 120 mm wide, and 270 mm high. It's not a DIN-rail mount — it's a standalone IP65 enclosure intended for wall or machine mounting. The main energy infeed and load-side outgoing feeder use sockets per ISO 23570, so the mating connectors must be ordered separately if not already in hand. Supply voltage is 24 V DC nominal (20.4 to 28.8 V range, max 31.6 V). The AS-i cable provides both power and communication via the cutting/clamping method — no separate control wiring needed for the bus. A front addressing socket allows configuration without opening the enclosure.