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Do your sensors tell you everything?
Since their introduction as an automation component presence and proximity sensors have been the eyes & ears of the control system. The component that is in direct contact with the process – and therefore exposed to potential damage.
The vast majority of sensors only provide a simple digital on/off output, nothing about their status, condition or performance.
Before the creation of IO-Link – a sensor level I/O standard – this information was unknown, and while more advance sensors using Ethernet/IP, Profinet or DeviceNet may have been able to provide status information your basic photoelectric or inductive sensor could not.
IO-Link is set to change all this and allow sensors to convey status and other information – all via the same wiring that the sensors have used previously – via a gateway back to the PLC or control system.
IO-Link in maintenance and repair
With IO-Link the last metre between the field level of automation and the sensor/actuator level becomes communication-capable. This means that in addition to the process variables, information about identification, parameters and the status of the device can also be sent.
This helps avoid replacement with the wrong device model and sensor parameters can be stored in the controller and automatically transferred when the unit is replaced.
IO-Link simplifies equipment replacement, reduces the level of training required, reduces maintenance costs through better diagnostics and prevents downtimes.

IO-Link reduces maintenance costs while increasing equipment uptime
IO-Link devices can provide information about their basic status. For example, the increasing contamination level of an optical sensor can be reported and maintenance requested. These self-diagnosis functions and the ability to convey information back to the control system enables greater levels of predictive maintenance, less preventative maintenance and uptimes are increased.
Upgrade existing equipment and designs with minimal cost
One of the biggest benefits of IO-Link technology is its use of existing wiring. It transmits the additional information via the 3-wire connection used by the sensor or actuator without affecting its basic operation.
This means IO-Link is invisible to the system unless a gateway is used to interface with this data, which allows IO-Link enabled sensors to be implemented into existing machines or designs with minimal re-work.
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So what does this mean to the industrial end user?
IO-Link technology has been rapidly gaining acceptance since its launch in 2009, with over 160 manufacturers now supporting the technology. IO-Link is an open-standard, and has been adopted as an international I/O standard (IEC 61131-9) allowing different brands of actuators and sensors on a machine all to communicate with the control system.
This high level of manufacturer support, openness and ability to retro-fit IO-Link to existing processes and designs means you should be demanding IO-Link support from machine build and integration partners now to ensure you can gain the operational benefits.
We’ve been expanding our IO-Link range and now have nearly 400 enabled products in stock, giving you the opportunity to design or upgrade machines with this game changing I/O technology.