The Siemens 3RK1207-3CE00-2AA2 is a Slimline Compact I/O module for control-cabinet use, part of the AS-Interface SC22.5 family. It provides four analog inputs (16-bit A/D resolution) accepting Pt100 standard and climate range, Ni100, and 0...600 Ohm resistance measurements — no analog or digital outputs on this variant. The module is a standard AS-Interface slave with profile S-7.3.E, powered directly from the AS-Interface bus (18...31.6 V operating voltage per AS-Interface specification). An external auxiliary feed (AUX POWER) of 20...30 V DC, compliant with IEC 60990 (PELV, protection class III), is required to supply the output circuits — a critical detail for panel wiring. Input variable and smoothing are both parameterizable, giving the integrator flexibility to tailor the analog channel response per sensor type without hardware changes.
The module measures 22.5 mm wide by 100 mm high by 120 mm deep. Fastening is via screw and snap-on mounting. IP20 rated, it is intended for dry, clean control-cabinet environments — not for washdown or outdoor deployment. The screw terminals accept solid conductors 1x (0.5...2.5 mm²) or 2x (0.5...1.5 mm²), and finely stranded wire with ferrule 1x (0.25...2.5 mm²) or 2x (0.25...1.0 mm²). Stranded wire without ferrule is not permitted. Shock resistance is rated at 15g / 11 ms for the module alone, or 10g / 11 ms with the device connector attached — worth noting if the panel is on a moving machine axis.