CPU 1212C with full communication stack
This 6ES7212-1HE31-0XB0 is the Siemens SIMATIC S7-1200 CPU 1212C, a compact controller that runs programs in FBD, LAD, or SCL. It draws power from a 24 V DC supply rated for 20.4 V to 28.8 V, staying within safe margins for industrial 24 V rails. The CPU integrates 1 Mbyte work memory, enough for moderate machine logic and small data blocks. Digital and analog I/O maps to 1 024 byte each. Forcing is supported, allowing output override during commissioning without altering the program.
Mounting and environmental limits
Dimensions are 90 mm wide, 100 mm high, 75 mm deep — fits standard DIN-rail enclosures with adequate side clearance for airflow. The ambient temperature range spans -40 °C to 70 °C, allowing installation in unheated cabinets or near process heat, provided derating guidelines for adjacent modules are observed. A typical backup time of 480 hours retains the program and volatile tags during power loss, suiting batch processes where overnight shutdowns are routine. The real-time clock and memory bits hold without external battery packs.
Approvals and compliance footprint
Carries cULus, CE, FM, UL, and CSA marks, clearing most North American and European machinery directives. The CE mark indicates compliance with EMC and low-voltage requirements; FM approval covers hazardous-location installations up to Class I Div 2. PROFIBUS and MODBUS (TCP/IP and RTU) are native, along with UDP and AS-Interface master capability. The CPU can act as both Modbus client and server, simplifying integration with older field devices without a separate gateway.