The Siemens 3RK1322-0AS12-0AA1 is an AS-Interface compact starter from the SIRIUS family — a fully enclosed, solid-state electronic DOL (direct-on-line) starter in an IP65-rated housing. It integrates motor protection, switching, and AS-i bus communication into one field-mounted unit, eliminating the need for a separate control cabinet for small motor branches. The solid-state design means no mechanical contacts to wear, and the motor protection is electronic (not a bimetal relay), so it tracks true motor heating rather than just current magnitude. The setting range of 0.6 to 2.18 A covers small motors from 0.18 kW up to 0.8 kW at 400 V AC-3 duty — typical for pumps, fans, conveyors, and small agitators on automated lines. The tab terminals for the main circuit and the AS-i bus connection keep field wiring straightforward.
The headline rating is the AC-3 motor power: 0.8 kW at 400 V. That is the maximum three-phase induction motor this starter can switch under full-load starting conditions. The minimum setting of 0.18 kW means it can also protect a very small motor without needing an external current transformer. The short-circuit breaking capacity (Icu) is 100 000 A at 400 V. That is exceptionally high for a compact starter — it means this unit can be installed downstream of a high-capacity distribution board without needing a separate current-limiting fuse upstream, provided the prospective fault current does not exceed 100 kA. The required short-circuit protection is a fuse (the design assumes a fuse upstream, not a MCCB). The integrated brake output (24 V DC, 3 A) is for externally supplied brakes — common on small crane, hoist, or vertical-conveyor motors where the brake must release before the motor starts and engage when power is removed. The brake contact is driven from the same AS-i command, so no separate brake control relay is needed. Two integrated inputs (sensors or pushbuttons) can be wired directly to the starter, reducing the need for separate AS-i I/O modules at the motor location.
Integration notes
The housing dimensions are 190 mm deep, 120 mm wide, 270 mm high. It mounts via the IP65 enclosure's own fixing points — not a DIN rail — so panel cut-outs or machine-frame brackets need to accommodate that footprint. The tab terminals for the main circuit accept standard fork or ring terminals; the AS-i connection uses the standard yellow flat cable piercing technique or an M12 connector variant. AS-Interface protocol is the only fieldbus on this variant (no PROFIBUS DP). The bus communication is built in, so no external gateway is required for AS-i master connectivity. The two integrated inputs can be configured as 24 V DC sensors or dry-contact pushbuttons, reducing field wiring to the motor location.