The Siemens 3RK2200-0DQ20-0AA3 is a K45 compact digital input module for field deployment — 8 PNP inputs, zero outputs, housed in a 45 mm wide IP67 enclosure. It takes a 16.5 to 30 V sensor supply and communicates via a front double-addressing socket that assigns two AS-Interface addresses to the module. Each input is wired through standard M12 sockets (PIN 4 = data input 1, PIN 2 = data input 2) using 2- or 3-wire PNP sensors. The module needs two consecutive AS-i addresses — the first socket pair maps to address 1, the second pair to address 2.
The 200 mA total current limit covers all eight inputs plus the sensor supply L+ pin. At 40 °C ambient, that's the hard ceiling — each input draws at least 6 mA in the high state, so worst-case eight active inputs pull 48 mA, leaving 152 mA for external sensor loads. Watch the sum if you're powering prox sensors through the module. IP67 means the module body and M12 sockets tolerate washdown and dust — it mounts directly on the machine frame, not inside a panel. Standard rail mounting or wall mounting via the K45 mounting plate. The input switching threshold is 10 V minimum for a high signal. With a 16.5 V minimum supply, that leaves 6.5 V of margin for cable drop — fine for runs up to maybe 30 m with 0.75 mm² cable, but check voltage at the sensor if you're pushing longer distances.
Dimensions are 45 mm wide × 80 mm high × 30 mm deep. The M12 sockets face outward, so plan for gland-plate clearance on the cable exit side. Modules ship without the mounting plate — order the K45 mounting plate separately if you're not using DIN rail. Grounding uses PIN 5 on each M12 socket, daisy-chained through a flat tab sleeve (2.8 × 0.8 mm form A). Keep the ground chain continuous and short to maintain EMC performance in the field.