The central processing units of the SIMATIC S7-1200 are designed as Compact CPUs with integrated I/Os. Their modular design can be used to increase the configuration limits or to adapt the controller to new tasks: through mounting a Signal Board on the CPU or adding separate signal modules.
Signal modules can be connected to the right of the CPU to further extend the digital or analog IO capacity. CPU 1212C accepts up to two, CPU 1214C, CPU 1215C and CPU 1217C both accept up to eight signal modules.
Signal boards can be added to the CPU to increase the number of digital or analog inputs and outputs, RS485 communication, and battery board to the controller for your application requirements without increasing the controller's footprint.