Various CPUs with graduated levels of performance are available for SIMATIC S7-300. Compact CPUs can be used in addition to the standard CPUs.
Technology CPUs and fail-safe CPUs are also available.

The following standard CPUs are available

• CPU 312 for small plants
• CPU 314 for plants with additional requirements on the program scope and the instruction processing speed
• CPU 315-2 DP for plants with medium to high requirements on the program scope and distributed configuration using PROFIBUS DP
• CPU 315-2 PN/DP for plants with medium to high requirements on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO; these can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET
• CPU 317-2 DP for plants with high requirements on the program scope and distributed configuration using PROFIBUS DP
• CPU 317-2 PN/DP for plants with high requirements on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO; these can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET
• CPU 319-3 PN/DP for plants with very high requirements on the program scope and networking as well as distributed configuration using PROFIBUS DP and PROFINET IO; these can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET
  

The following compact CPUs are available:

• CPU 312C, the compact CPU with integrated digital inputs/outputs and integrated counting function
• CPU 313C, the compact CPU with integrated digital and analog inputs and outputs
• CPU 313C-2 PtP, the compact CPU with integrated digital inputs/outputs, second serial port and integrated counting function
• CPU 313C-2 DP, the compact CPU with integrated digital inputs/outputs, PROFIBUS-DP port and integrated counting function
• CPU 314C-2 PtP, the compact CPU with integrated digital and analog inputs/outputs, second serial port and integrated counting and positioning functions
• CPU 314C-2 DP, the compact CPU with integrated digital and analog inputs/outputs, PROFIBUS-DP port and integrated counting and positioning functions
• CPU 314C-2 PN/DP, the compact CPU with integrated digital and analog inputs/outputs and the integrated counting and positioning functions;
  with the option of a distributed topology via PROFIBUS DP and PROFINET IO;
  can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET
  

The following technology CPUs are available:

• CPU 315T-3 PN/DP for plants with medium/high requirements in terms of program scope and distributed setup using PROFIBUS DP and PROFINET IO, which also require regulated motion control of up to 8 axes.
• CPU 317T-3 PN/DP for plants with high demands on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO, which also require regulated motion control of up to 32 axes.
• CPU 317TF-3 PN/DP for plants with high demands on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO, which require safety functions and also regulated motion control of up to 32 axes.

The following failsafe CPUs are available:

• CPU 315F-2 DP for failsafe plants with medium to high requirements on the program scope and distributed configuration using PROFIBUS DP
• CPU 315F-2 PN/DP for failsafe plants with medium to high requirements on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO; these can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET
• CPU 317F-2 DP for failsafe plants with high requirements on the program scope and distributed configuration using PROFIBUS DP
• CPU 317F-2 PN/DP for failsafe plants with high requirements on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO; these can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET
• CPU 319F-3 PN/DP for fail-safe plants with very high requirements on the program scope and distributed configuration using PROFIBUS DP and PROFINET IO; these can be implemented as distributed intelligence in Component Based Automation (CBA) on PROFINET