What it is and what drives the fit
The Siemens 3RK1322-1HS02-0AA3 is an AS-interface compact starter — a self-contained direct-on-line motor starter in an IP65 enclosure rated for washdown environments. It integrates the contactor, bimetal overload relay, short-circuit protection coordination, and AS-i bus communication into one package that mounts directly on the machine frame, not inside a control cabinet. The headline rating is 3 kW at AC-3 duty at 400 V, with an adjustable setting range of 5.5 to 8 A. That 3 kW figure at 400 V AC-3 is the motor-switching rating — it governs what induction motor this starter can handle under full-load starting. The bimetal overload element provides thermal protection matched to the motor's heating curve, not an electronic trip curve. The IP65 rating means the entire assembly — contactor, overload, bus node, and connections — is protected against dust ingress and low-pressure water jets from any direction. This is the spec that lets you mount it on a conveyor frame, a packaging machine, or a pump skid without a separate enclosure. The 9-pole motor and power connections use tab terminals (fast-on connectors), not screw terminals, which speeds field wiring but requires matching tab receptacles.
Bus integration and auxiliary functions
AS-interface protocol is onboard — no external gateway or bus coupler needed for AS-i line integration. The starter communicates directly with the AS-i master, reporting motor status and overload trips over the yellow AS-i flat cable. Two integrated digital inputs are available for local sensors (e.g., limit switches or proximity sensors), which are read via the same AS-i connection without additional I/O modules. A motor brake output is integrated, rated for 400 V AC. This saves an external contactor and wiring when the application uses a mechanical brake — typical for vertical-axis conveyors or hoists where the brake must engage when the motor is de-energized. The brake output is switched by the same AS-i command that controls the starter, so brake timing is coordinated in the bus logic. Short-circuit protection is designed for coordination with upstream circuit-breakers, not fuses. The maximum short-circuit breaking capacity (Icu) at 400 V is 50,000 A — this is the fault current the device can safely interrupt without catastrophic failure. For a machine-mounted starter, this high SCCR rating means it can be fed from a distribution panel with substantial available fault current without needing a current-limiting fuse ahead of it.
Lifecycle and sourcing reality
The part carries the SIRIUS brand and is designed to DIN EN 61346-2 equipment marking (function code Q for motor starter). Compliance documentation (CE, RoHS, REACH) is standard with Siemens industrial products from this series. No UL listing is explicitly stated in the available data, so verify UL acceptance for North American installations if required.
Deployment context
The IP65 enclosure and AS-i bus integration make this starter suited for distributed motor control on conveyors, packaging lines, material handling systems, and food-and-beverage equipment where the starter must live on the machine, not in a panel. The 5.5 to 8 A setting range covers small three-phase motors in the 2.2 to 3 kW range at 400 V. Ambient temperature range of -25 to +55 °C covers most industrial floor environments without derating.