The Siemens 3RK1207-1BQ40-0AA3 is an AS-Interface compact module in the K60 form factor, designed as an analog input slave for field-mounted current measurement. It provides two analog inputs accepting 4-20 mA or ±20 mA signals from 2-, 3-, or 4-conductor sensors, with a 16-bit A/D converter for the measurement path. The module is powered from the AS-Interface bus (26.5-31.6 V per the AS-i specification) and additionally requires an auxiliary supply Uaux at 24-30 V for sensor excitation. Maximum current draw from the AS-i profile conductors is 160 mA at 30 V; the auxiliary supply can deliver up to 500 mA to the sensors. The IP67 rating means the sealed housing withstands washdown environments and dust ingress — suitable for direct mounting on conveyors, packaging lines, or machine frames where the module lives alongside the sensors rather than in a control cabinet.
Sensor connections use M12 screw-type terminals (4-conductor wiring), with channels 1 and 2 active. The I/O configuration code is 7, and the ID code is 3 — these must match the AS-i master's configuration database.
Configuration and diagnostics
The input variable (current) is parameterizable, and a configurable smoothing function is available for noisy signals. The measuring/output range is adjustable between 4-20 mA and ±20 mA, set via the AS-i master or configuration tool. Diagnostic LEDs on the module face: green for AS-Interface communication, green for auxiliary power Uaux present, and red for a fault condition. Profile 7.3 defines the data exchange format with the master.