What it is and what it does
The Siemens 3RK1322-0JS02-1AA4 is an AS-interface compact reversing starter in the SIRIUS family — a fully integrated motor-starting and reversing unit rated for 0.25 kW at 400 V in AC-3 duty (switching motor loads under full load). The setting range spans 0.7 to 1 A, using a bimetal overload relay for motor protection. Short-circuit protection is built in via integrated circuit-breakers, and the electromechanical switching contacts handle the reversing function without an external contactor pair. The enclosure carries an IP65 rating, meaning the housing and all connections are sealed against dust ingress and low-pressure water jets — suited for washdown zones, outdoor conveyor sections, or food-and-beverage lines where a panel-mounted starter would require a separate enclosure. It communicates directly on the AS-Interface network (the protocol is listed as supported), and includes a motor brake output rated at 500 V DC / 1 A, plus two integrated inputs for local sensors or pushbuttons. The main current circuit connects via tab terminals, common for quick-connect field wiring in distributed installations.
Key ratings and what they mean for fit
The AC-3 rating of 0.25 kW at 400 V is the headline motor-switching capability — it covers small three-phase induction motors up to that power. The setting range of 0.7 to 1 A means the bimetal overload is adjustable within that window; if your motor's full-load current falls outside that band, this starter will not provide proper overload protection. The maximum short-circuit breaking capacity (Icu) at 400 V is 50,000 A — meaning the integrated short-circuit protection can safely interrupt a fault current up to that level without external fusing or a separate breaker upstream, provided the supply-side SCCR is coordinated. This is a high interrupting rating for a compact starter, typical of the SIRIUS design. Dimensions are 270 mm high, 120 mm wide, and 190 mm deep. The 120 mm width matches the standard SIRIUS compact starter footprint; it will fit the same mounting pattern as other SIRIUS reversing starters of this class. The IP65 enclosure means it mounts directly on the machine frame or a wall bracket — no separate panel enclosure needed.
Integration notes
The AS-Interface connection carries both power and communication on the same two-wire yellow flat cable, so no separate control wiring is needed for the network. The two integrated inputs can be used for local start/stop or sensor feedback, reducing the need for a remote I/O block. The brake output (500 V DC / 1 A) is available for holding brakes on vertical-axis motors. Operating ambient temperature range is -25 to +55 °C, which covers most indoor and outdoor installations in temperate climates. Above that, derating may apply — the datasheet should be consulted for thermal performance at the upper end.