What this is and where it fits
The Siemens 6AG1211-1HE31-2XB0 is a SIPLUS variant of the S7-1200 CPU 1211C, built for applications needing a wider operating temperature range of -40°C to 70°C and a permissible 24 V DC supply from 20.4 V to 28.8 V. It runs standard TIA Portal projects using LAD, FBD, or SCL and communicates over PROFINET with integrated MODBUS TCP and UDP client/server capability.
Key ratings for the sourcing decision
Integrated memory is 1 Mbyte, with a backup time of 480 h (typical) to retain data on power loss. The process image size is 1 024 bytes each for inputs and outputs, which defines the maximum addressable I/O, not the physical count. Forcing of inputs and outputs is supported, and the voltage supply is isolated. In addition to PROFINET, the CPU supports MODBUS (RTU and TCP), UDP, PROFIBUS (as master via CM?), and AS-Interface via CM modules. The PROFINET interface has autocrossing and autonegotiation, and shielded cable runs up to 100 m twisted-pair. No PROFIsafe onboard – that requires an external F-module.
Physical dimensions
Dimensions are 90 mm wide, 100 mm high, and 75 mm deep – the same footprint as the standard S7-1200 CPU 1211C. Panel cutout and DIN rail clip are identical, so a swap from a standard model to this SIPLUS version requires no enclosure modification.