Many of the sensors you use have IO-Link capability built in. But you might not know it, because they can still be used like standard sensors. For instance, all Pepperl+Fuchs IO-Link sensors boot up first in digital IO mode; they will only switch to IO-Link mode when an IO-Link master actively communicates with them.
The decision to equip almost all of our new sensors with IO-Link was a no-brainer for Pepperl+Fuchs—it adds little or no additional hardware cost while drastically increasing the functional capability of the sensors. And now with SmartBridge®, unlocking the full potential of your IO-Link sensor is easier than ever.
What is IO-Link?
Let’s start by talking about what it is not. It is not a network. It will not replace any of the known industrial networks like AS-Interface, Ethernet/IP, PROFINET, or EtherCAT. IO-Link actually works seamlessly with all of these networks.
IO-Link is a simple, flexible, and secure open communication technology that enables continuous communication at the sensor level. It opens up configuration, control, and diagnostic capabilities of sensors while minimizing the cost of project implementation, diagnostics, and downtime. And it uses the same digital lines that you normally use for your sensor outputs, which means that you don’t need new digital IO-Link cards for communication to your control system.
You could buy an IO-Link master to take full advantage of the sensors’ capability. The master could be built into a PLC IO rack or built into an industrial bus module—typically Ethernet—but PROFIBUS, DeviceNet, or AS-Interface are also possible. You don’t have to turn to one of these fancy IO-Link masters to use IO-Link, though. You could simply use SmartBridge.
What is SmartBridge®?
SmartBridge technology is a wireless interface that bridges the gap between the IO-Link sensor, the user, and the PLC. It is the middleman that will communicate IO-Link to the sensor, allowing you to configure the sensor’s parameters, view the output data, and troubleshoot a system. The digital data is still passed on to the PLC, so the industrial process can continue running without interruption.
Once you are happy with the performance of the sensor, the SmartBridge interface can either be left in place to continuously monitor the operation or removed and saved for the next IO-Link sensor. Because SmartBridge is often not left in place or only left in place in very hard-to-reach locations or mission-critical applications, an entire plant may only need two or three of these devices.
What information do you get from IO-Link and SmartBridge?
A normal sensor will have up to three digital outputs. These could be set points as a target moves in and out of the sensing window, but what is the distance? All IO-Link measurement sensors will transmit in the process IO-Link data distance information along with the set point data. This allows you to see if the set points are even in the correct location. If the set points are wrong, you can quickly and easily change them and then verify the correct operation of the sensor.
I already mentioned that you can easily change the set points, but you can do much more than this. You can completely configure how an output functions by changing the hysteresis to remove output jitter, adding an on-delay time to eliminate false trips caused by noise in the environment, and then configure the output state by making it an active high or active low signal. I have only mentioned four of the over 50 configurable parameters for an IO-Link sensor. Once the parameters are configured, you can lock them to make the sensor tamper proof or store them for later use in another sensor.
Have you ever gotten a call in the middle of the night or were told by second shift that a specific piece of equipment or sensor was acting up? Now you have a way to log the sensor use data and view it later. The SmartBridge hardware will log all changes in process data directly to a memory card.
Even frequently changing high-use sensors can store data for 20+ days without running out of room on a small 4 Gigabyte memory card. Once the SmartBridge is plugged into a PC using the Micro USB port, the data is simply copied to your local computer. A simple, free Excel sheet macro will extract the compact data set and give you complete visualization or your process. All data is time stamped so you can pinpoint the problem and get back to fixing it. We all know that if you can’t record and duplicate the problem then you can’t fix it. SmartBridge can help you do that.
Equipping the Plant of the Future
Just because you’re not using IO-Link doesn’t mean you shouldn’t. Consider specifying IO-Link as a requirement for all sensors in the future. This added functionality adds little cost to your installation but gives you a lot of configuration and diagnostic capabilities that you didn’t have before. If the sensor has IO-Link and you don’t use it, no problem—your control system won’t know the difference. It is better to future-proof your technology purchases and then utilize the technology as you need it in the future.