An IO-Link system consists of an IO-Link Master, IO-Link Devices and the cables that connect the IO-Link Devices to the IO-Link Master’s ports. The IO-Link Master establishes the connection between the IO-Link Devices and the automation system and maintains point-to-point connections to the IO-Link Devices. Figure 1 gives an example of a system architecture with IO-Link.
Figure 1 uses the following colour code: Green for Ethernet and Fieldbus connections, orange for IO-Link connections and black for non-IO-Link sensor/actuator connections. Note that IOLink Masters can be implemented at different levels of the hierarchy and be combined with different kinds of devices such as fieldbus masters, gateways, etc.