In the early days of Ethernet, collisions on the network prevented its use in deterministic industrial applications. If two stations tried to transmit at the same time, a collision would result. The collision was detected and each station “backed off” a random time and tried again. This approach was fine for web browsing and email but prevented determinism. The advent of switched Ethernet networks did away will collisions allowing Ethernet to be applied in industrial automation where determinism was a must.

Did you know that IO-Link does away with the great variety of signals and interfaces on the sensor/actuator level once and for all? Naturally, sensors and actuators covering a wide range of complexity and characteristics were produced in the past, when there was no standard for an interface with communications capability. Today, IO-Link bundles up this variety and simplifies the last meter of the sensor-actuator level. The reason is that IO-Link needs nothing more than an M12 plug connection and a standard 3- or 5-wire sensor cable.

Did you know that IO-Link drastically reduces electrical installation costs? IO-Link results in significant cost savings even for classic binary sensors. For use as an installation system, IO-Link sensor hubs are available on the market that condense up to 16 binary sensors with one switching output or 8 sensors with two switching outputs (e.g. antivalent or Desina sensors) into a single serial IO-Link connection.

When a user decides on PROFINET, he has a choice of thousands of different products developed and available worldwide today, such as I/O devices, actuators, sensors, network and infrastructure components, and controllers. This variety gives the user maximum freedom to design his own plant and automation systems. The device manufacturer has access to a wide range of different hardware- and software-based basic technologies for optimal implementation of the PROFINET interface based on his requirements.

In part 3 of this series of tech tips, we’ll cover PROFINET application layer device diagnostics and alarms, data records, and additional features, which give us complete accessibility and control in the event of a diagnostic or issue with the network. We often refer to this as “diagnostics down to the wire.” The article explains this concept.