Sensors and actuators are connected by means of generally available 5-pin M12 connectors, 8-pin M12 connectors, 3-pin M8 connectors, and 12-pin M23 connectors.

For the digital input modules and digital output modules, the following connection variants are available in combination with IO connection modules:

• CM IO 4x M12; can be used with an 8-channel digital input module, 4- or 8-channel digital output module, 8-channel digital hybrid module 4 DI/4 DO, and analog modules
• CM IO 4x M12 P (plastic version); can be used with an 8-channel digital input module, 4- or 8-channel digital output module, and 8-channel digital hybrid module 4 DI/4 DO
• CM IO 4x M12, inverse; can be used with a 4-channel digital output module
• CM IO 8x M12; can be used with an 8-channel digital input module, 8-channel digital output module, and 8-channel digital hybrid module 4 DI/4 DO
• CM IO 8x M12 P (plastic version); can be used with an 8-channel digital input module, 8-channel digital output module, and 8-channel digital hybrid module 4 DI/4 DO
• CM IO 8x M12 D; can be used with a 16-channel digital input module and 8-channel digital hybrid module 4 DIO/4 DO
• CM IO 8x M8; can be used with an 8-channel digital input module, 4- or 8-channel digital output module, and 8-channel digital hybrid module 4 DI/4 DO
• CM IO 2x M12 (plastic version); can be used with an 8-channel digital input module, 4- or 8-channel standard digital output module, and 8-channel digital hybrid module 4 DI/4 DO
• CM IO 1x M23 (plastic version); can be used with an 8-channel digital input module, 4- or 8-channel standard digital output module, and 8-channel digital hybrid module 4 DI/4 DO