Is IO-Link with Single Pair Ethernet the Future?

20 meters.

That is the maximum distance between an IO-Link master port and an IO-Link device using a standard prox cable.  Can this length be extended?  Sure, there are IO-Link repeaters you can use   to lengthen the distance, but is there an advantage and is it worth the headache?

I hope you like doing some math, because the maximum distance is based on the baud rate of the IO-Link device, the current consumption of the IO-Link device and finally the cross section of the conductors in the cabling.  Now throw all that into a formula and you can determine the maximum distance you can achieve.  Once that is calculated, are you done? No.  Longer cables and repeaters add latency to the IO-Link data transfer, so you may need to slow down the IO-Link master’s port cycle time due to the delay.

Luckily, there is a better and easier solution than repeaters and the sacrifice of the data update rate — Single Pair Ethernet (SPE).

SPE is being discussed in all the major communication special interest groups, so it makes sense that its being discussed within the IO-Link Consortium.  Why?  A couple of key factors: cable lengths and updated speeds.  By using SPE, we gain the Ethernet cable length advantage. So, instead of being limited to 20 meters, your IO-Link cabling could stretch to 100 meters!  Imagine the opportunities that opens in industrial applications.  It is possible that even longer runs will be achievable.  With 10 Mbit/s speed, to start, the update rate between IO-Link devices and the IO-Link master could be less than 0.1 millisecond.

Latency has been the Achilles heal in using IO-Link in high-speed applications, but this could eliminate that argument. It will still be IO-Link, the point-to-point communication protocol (master-to-device), but the delivery method would change. Using SPE would require new versions of IO-Links masters, with either all SPE ports or a combination of SPE and standard IO-Link ports. The cabling would also change from our standard prox cables to hybrid cables, containing a single twist Ethernet pair with two additional conductors for 24 volts DC.  We may even see some single channel converts, that convert standard IO-Link to SPE and vice versa.

There likely would have been pushback if this was discussed just five or ten years ago, but today, with new technology being released regularly, I doubt we see much resistance. We consumers are ready for this. We are already asking for the benefits of SPE and IO-Link SPE may be able to provide those advantages.

For more information, visit www.balluff.com.

Improve OEE, Save Costs with Condition Monitoring Data

When it comes to IIOT (Industrial Internet of Things) and the fourth industrial revolution, data has become exponentially more important to the way we automate machines and processes within a production plant. There are many different types of data, with the most common being process data. Depending on the device or sensor, process data may be as simple as the status of discrete inputs or outputs but can be as complex as the data coming from radio frequency identification (RFID) data carriers (tags). Nevertheless, process data has been there since the beginning of the third industrial revolution and the beginning of the use of programmable logic controllers for machine or process control.

With new advances in technology, sensors used for machine control are becoming smarter, smaller, more capable, and more affordable. This enables manufacturers of those devices to include additional data essential for IIOT and Industry 4.0 applications. The latest type of data manufacturers are outputting from their devices is known as condition monitoring data.

Today, smart devices can replace an entire system by having all of the hardware necessary to collect and process data, thus outputting relative information directly to the PLC or machine controller needed to monitor the condition of assets without the use of specialized hardware and software, and eliminating the need for costly service contracts and being tied to one specific vendor.

A photo-electric laser distance sensor with condition monitoring has the capability to provide more than distance measurements, including vibration detection. Vibration can be associated with loose mechanical mounting of the sensor or possible mechanical issues with the machine that the sensor is mounted. That same laser distance sensor can also provide you with inclination angle measurement to help with the installation of the sensor or help detect when there’s a problem, such as when someone or something bumps the sensor out of alignment. What about ambient data, such as humidity? This could help detect or monitor for moisture ingress. Ambient pressure? It can be used to monitor the performance of fans or the condition of the filter elements on electrical enclosures.

Having access to condition monitoring data can help OEMs improve sensing capabilities of their machines, differentiating themselves from their competition. It can also help end users by providing them with real time monitoring of their assets; improving overall equipment efficiency and better predicting  and, thereby, eliminating unscheduled and costly machine downtime. These are just a few examples of the possibilities, and as market needs change, manufacturers of these devices can adapt to the market needs with new and improved functions, all thanks to smart device architecture.

Integrating smart devices to your control architecture

The most robust, cost effective, and reliable way of collecting this data is via the IO-Link communication protocol; the first internationally accepted open, vendor neutral, industrial bi-directional communications protocol that complies with IEC61131-9 standards. From there, this information can be directly passed to your machine controller, such as PLC, via fieldbus communication protocols, such as EtherNET/Ip, ProfiNET or EtherCAT, and to your SCADA / GUI applications via OPC/UA or JSON. There are also instances where wireless communications are used for special applications where devices are placed in hard to reach places using Bluetooth or WLAN.

In the fast paced ever changing world of industrial automation, condition monitoring data collection is increasingly more important. This data can be used in predictive maintenance measures to prevent costly and unscheduled downtime by monitoring vibration, inclination, and ambient data to help you stay ahead of the game.

Use IODD Files with IO-Link for Faster, Easier Parameterization

Using IO-Link allows you to get as much data as possible from only three wires. IO-Link communicates four types of data: device data, event data, value status, and process data. Value status data and process data are constantly sent together at a known rate that is documented in each device’s manual and/or data sheet. Device and event data stores your device parameters and allow for the ultimate flexibility of IO-Link devices. Since the IO Device Description (IODD) files contain each device’s full set of parameters, using them saves you from the need to regularly refer to the manual.

Commissioning IO-Link devices

When first using an IO-Link device, the standard process data will be displayed. To maximize the functionality of the device, parameters can be accessed and, in some cases, changed.  The available parameters for any IO-Link device are located in at least two places: the device’s manual and the device’s IODD file.  The manual will display the required hexadecimal-based index and sub-index addresses to point your controller’s logic, which will allow the user to change/monitor parameters of the device during operation.  This is great for utilizing one or two parameters.

However, some devices require a large number of parameter adjustments to optimize each device per application.  Using IODD files to commission devices can be faster and make it easier to select and change parameters, because all available parameters are included in the XML based file.  Certain masters and controllers have the ability to store these IODD files, further improving the integration process.  Once the IODD files are stored and the device is plugged into an IO-Link port, you can choose, change, and monitor every parameter possible.

Where can I find IODD files?

The IO-Link consortium requires all IO-Link device manufacturers to produce and post the files to the IODD finder located on io-link.com.  Most IO-Link device manufacturers also provide a link to the IODD file on the product’s web page as well as the IO-Link.com site.

Industry 4.0: What It Is and How It Improves Manufacturing

Industry 4.0 is a common buzzword that is thrown around along with IIoT and Process visualization but what does that mean and how is it integrated into a manufacturing process? Industry 4.0 refers to the fourth industrial revolution. The first dealing with mechanization and the use of steam and water power, the second referring to mass production using assembly lines and electrical power, and the third referring to automated production and the use of computers and robots. Industry 4.0 takes us a step beyond that to smart factories that include automation and machine learning. Again, buzzwords that can be hard to visualize.

A commonplace example of this would be self-driving cars. They are autonomous because they don’t need a person operating them and they take, in real time, information about their surroundings and use that to determine a course of action. But how can this type of technology affect a manufacturing process?

Industry 4.0 requires data to be analyzed. This is where IO-Link comes into play. With IO-Link, you are able to get information from a sensor more than than just an output signal when it detects a part. A photoelectric sensor is a good example of this. The basic way a photoelectric sensor works an output is given depending on the amount of light being received. If the sensor happens to be in a dirty/dusty environment, there could be dirt collecting on the lens or floating in the air which effects the amount of light being received. An IO-Link (smart) sensor can not only fire an output when detection occurs but can give information about the real time gain of the sensor (how much light is being received). If the gain drops below a certain amount because of dirt on the lens or in the air, it can send another signal to the controller indicating the change in gain.

Now that we have more data, what are we going to do with it?

We now have all of this data coming from different parts of the machine, but where does it go and what do we do with it? This is where process visualization comes into play. We are able to take real time data from a machine and upload it to a database or system that we can monitor outside of the plant floor. We can know if a machine is running properly without having to physically see the machine. The information can also give us indications about when something might fail so preventative maintenance can take place and reduce downtime.

As more manufacturing processes are becoming automated, machines are becoming more and more complex. A machine might be needed to run 6-7 different lines rather than just 1 or 2 which can involve things like tool change or settings changes. Then, more checks need to be in place, so the right process is running for the right part. Industry 4.0 is how we are able to gather all this information and use it to increase efficiency and productivity.

Adding Smart Condition Monitoring Sensors to Your PLC Control Systems Delivers Data in Real Time

Condition monitoring of critical components on machines delivers enormous benefits to productivity in a plant.  Rather than have a motor, pump, or compressor unexpectedly fail and the machine be inoperable until a replacement part is installed, condition monitoring of those critical pieces on the machine can provide warning signs that something is about to go terribly wrong. Vibration measurements on rotating equipment can detect when there is imbalance or degrade on rolling bearing elements. Temperature measurements can detect when a component is getting overheated and should be cooled down. Other environmental detections such as humidity and ambient pressure can alert someone to investigate why humidity or pressure is building up on a component or in an area. These measurement points are normally taken by specific accelerometers, temperature probes, humidity and pressure sensors and then analyzed through high end instruments with special analysis software. Typically, these instruments and software are separate from the PLC controls system. This means that even when the data indicates a future potential issue, steps need to be taken separately to stop the machine from running.

Using smart condition monitoring sensors with IO-Link allows these measured variables and alarms to be available directly onto the PLC system in real time. Some condition monitoring sensors now even have microprocessors onboard that immediately analyze the measured variables. The sensor can be configured for the measurement limit thresholds of the device it’s monitoring so that the sensor can issue a warning or alarm through the IO-Link communications channel to the PLC once those thresholds have been hit. That way, when a warning condition presents itself, the PLC can react immediately to it, whether that means sending an alert on a HMI, or stopping the machine from running altogether until the alarmed component is fixed or replaced.

Having the condition monitoring sensor on IO-Link has many advantages. As an IEC61131-9 standard, IO-Link is an open standard and not proprietary to any manufacturer. The protocol itself is on the sensor/actuator level and fieldbus independent. IO-Link allows the condition monitoring sensor to connect to Ethernet/IP, Profinet & Profibus, CC-Link & CC-Link IE Field, EtherCAT and TCP/IP networks regardless of PLC. Using an IO-Link master gateway, multiple smart condition monitoring sensors and other IO-Link devices can be connected to the controls network as a single node.

The picture above shows two condition monitoring sensors connected to a single address on the fieldbus network. In this example, a single gateway allows up to eight IO-Link condition monitoring sensors to be connected.

Through IO-Link, the PLC’s standard acyclic channel can be used to setup the parameters of the measured alarm conditions to match the specific device the sensor is monitoring. The PLC’s standard cyclic communications can then be used to monitor the alarm status bits from the condition monitoring sensor.  When an alarm threshold gets hit, the alarm status bit goes high and the PLC can then react in real time to control the machine. This relieves the burden of analyzing the sensor’s condition monitoring data from the PLC as the sensor is doing the work.

 

IO-Link Simplifies Connectivity on Robotic End-Effectors

In my last two blogs, Rise of the Robots: IO-Link… and Realize Productivity Gains with Smart Robotic Tooling , I shared how implementing IO-Link and incorporating pneumatic and electric smart grippers can help maximize your use of robotics in your applications. In this blog, I will discuss how you can get more from your robots through expanded use of end-effectors in your applications.

As pneumatic air and vacuum systems have been an integral part of automation projects of the past, these systems can also benefit from gains in intelligence moving forward. Smart vacuum generators can provide feedback on the operation of the system; for example, if cups are starting to wear or fail, the smart devices can be used to provide estimates on remaining service life through predictive maintenance calculations. Key components like process sensors, variable regulators, pneumatic grippers, and pneumatic valve manifolds are available with IO-Link technology at a reasonable price. More importantly, these devices dramatically simplify integration, installation, and maintenance with built-in diagnostics and parameterization tools. By utilizing smart pneumatics, we substantially reduce wiring complexity in new installations and expedite downtime repairs.

Easier I/O and Connectivity on Robotic End-Effectors

Figure 1 – An industrial robot with IO-Link I/O hubs and valve manifold control on the EoAT.

However, most people avoid adding these types of smart technologies to end-effectors due to cable management issues or the effort to put high-flex Ethernet or many conductors into the robot dress pack. With IO-Link and its use of standard conductors for communication, integrators and machine builders have been able to install already available conductors in the arm or use lower-cost high-flex sensor cables to communicate with IO-Link smart devices on the end of arm tooling (EoAT).

Smart I/O hubs allow for standard sensors to be used with simplified wiring and on large tooling, valve manifolds can be mounted and controlled on the EoAT (Figure 1). If tool change is needed for the application, non-contact wireless connectivity can send power and signal across an airgap, increasing application capabilities and functionality.

Manufacturers big and small have gained impressive intelligence at the robot’s end-effector using IO-Link electric grippers, smart pneumatics and tooling enabled with IO-Link sensors. As you look to your next robotic automation project, consider how you could reduce integration efforts, improve part quality, enhance production flexibility, gain more process visibility, and increase application capabilities of EoAT. To realize all the benefits of an industrial robot system and earn productivity gains in machine tending, assembly and material handling applications, smart grippers, smart sensors, and smart tooling (enabled by IO-Link) are a necessary part of your next smart factory project.

Realize Productivity Gains with Smart Robotic Tooling

In my last blog post, I shared how implementing IO-Link can expand visibility into your robot implementations and secure a high ROI. In this blog, I will share how you can better capitalize on your robot utilization and gain productivity with pneumatic and electric smart grippers.

Using Pneumatic & Electric Smart Grippers

Figure 1 – Sensors used in grippers provide position and open/closed feedback of the jaw. Photo courtesy of Balluff Worldwide.

In traditional pneumatic gripper applications, sensors are often not utilized. Proper function is assumed, i.e., the jaw opened and closed properly based on the signal sent to the air valve. This can cause unnecessary collisions or process failures due to stuck/worn mechanical components, leaks in the pneumatic lines, or small variations in the process cycle. Adding sensors to the grippers (Figure 1), creates a closed loop and minimal discrete feedback, like open or closed jaw, is provided. With the addition of smart sensors, we can monitor exact gripper jaw position and provide application diagnostics improving the capabilities of the robot end-effector. And finally, gripper intelligence features are expanded even further with electric grippers, giving precise control over the motion profile of the tool and providing detailed condition data on the equipment.

Regularly for smart sensors and smart grippers, these commands and the data are handled via IO-Link communication, which allows for process data, parameter data, and event data to be shared with the PLC and monitored via the Industrial Internet of Things (IIoT) connections. By utilizing IO-Link, both electric and pneumatic grippers can be enabled with intelligence to improve robot implementations.

Part Quality, Inspection, Delicate Part Handling & Measurement

Some of the most common applications like bin-picking, part stacking, or blank de-stacking make assumptions about the part being handled. But the first assumption many people make is that the robot is holding a part. Without sensor verification that the part is in place, how can it be guaranteed that the process is running without defect? And a second assumption that the correct part was loaded into the machine by the operator can cause hundreds of part defects if continued without verification. It is vital that the right part is loaded into the equipment every time, and as many parts look very similar manual inspection isn’t always accurate.  A gripper is an excellent place to gauge and inspect parts as it is physically touching the part. This is done by utilizing an analog position measurement sensor to determine the distance change of the gripper jaw. In addition to this, the position measurement sensor also can provide feedback for tactile gripping applications when handling delicate or precise parts. By utilizing position sensing for inspection and handling of the part, we can improve part quality and reduce production defects.

Production Flexibility, Format Change & Part Identification

In addition to quality inspection, by measuring the part, we can identify the part and make automation changes on-the-fly based upon this information, creating much higher levels of flexibility and making it possible for in-process format change. With one piece of equipment and the utilization of smart sensors on pneumatic grippers or smart electric grippers, more product can be produced. With higher efficiencies manufacturers can realize significant productivity gains.

Figure 2 – GEH6060IL-03-B servo electric gripper with delicate or elastic parts. Photo courtesy of Zimmer Group US, Inc.

In my next blog, I will discuss how expanding the use of end-effectors adds flexibility and are now easier than ever to include in your robotic applications.

IO-Link Boosts Plant Productivity

In my previous blog, Using Data to Drive Plant Productivity, I categorized reasons for downtime in the plant and also discussed how data from devices and sensors could be useful in boosting productivity on the plant floor. In this blog, I will focus on where this data is and how to access it. I also touched on the topic of standardizing interfaces to help boost productivity – I will discuss this topic in my future blog.

Sensor technology has made significant progress in last two decades. The traditional transistor technology that my generation learned about is long gone. Almost every sensor now has at least one microchip and possibly even MEMs chips that allow the sensor to know an abundance of data about itself and the environment it which it resides. When we use these ultra-talented sensors only for simple signal communication, to understand presence/absence of objects, or to get measurements in traditional analog values (0-20mA, 0-10V, +5/-5V and so on), we are doing disservice to these sensors as well as keeping our machines from progressing and competing at higher levels. It is almost like choking the throat of the sensor and not letting it speak up.

To elaborate on my point, let’s take following two examples: First, a pressure sensor that is communicating 4-20mA signal to indicate pressure value. Now, that sensor can not only read pressure value but, more than likely, it can also register the ambient temperatures and vibrations. Although, the sensor is capable of understanding these other parameters, there is no way for it to communicate that information to the higher level controller. Due to this lack of ambient information, we may not be able to prevent some eminent failures. This is because of the choice of communication technology we selected – i.e. analog signal communication.

For the second example, let us take a simple photoeye sensor that only communicates presence/absence through discrete input and 0/1 signal. This photoeye also understands its environment and other more critical information that is directly related to its functionality, such as information about its photoelectric lens. The sensor is capable of measuring the intensity of re-emitted light, because based on that light intensity it is determining presence or absence of objects. If the lens becomes cloudy or the alignment of the reflector changes, it directly impacts the remitted light intensity and leads to sensor failure. Due to the choice of digital communication, there is no way for the sensor to inform the higher level control of this situation and the operator only learns of it when the failure happens.

If  a data communication technology, such as IO-Link, was used in these scenarios instead of signal communication, we could unleash these sensors to provide useful information about themselves as well as about their environment. If we collect this data or set alerts in the sensor for the upper/lower limits on this type of information, the maintenance teams would know in advance about the possible failures and prevent these failures to avoid eminent downtime.

Collecting this data at appropriate frequencies could help build a more relevant database and demonstrate patterns for the next generation of machine learning and predictive maintenance initiatives. This would be data driven continuous improvement to prevent failures and boost productivity.

The information collected from sensors and devices – so called smart devices – not only helps end users of automation to boost their plant’s productivity, but also helps machine builders to better understand their own machine usage and behaviors. Increased knowledge improves the designs for the next generation of machines.

If we utilized these smart sensors and devices at our change points in the machine, it would help fully or partially automate the product change-overs. With IO-Link as a technology, these sensors can be reconfigured and re-purposed for different applications without needing different sensors or manual tunings.

IO-Link technology has a built in feature called “automatic parameterization” that helps reduce plant down-time when sensors need replaced. This feature stores IO-Link devices’ configuration on the master port as well as all the configuration is also persistent in the sensor. Replacement is as simple as connecting the new sensor of the same type, and the IO-Link master downloads all the parameters and  replacement is complete.

Let’s recap:

  1. IO-Link unleashes a sensor’s potential to provide information about its condition as well as the ambient conditions, enabling condition monitoring, predictive maintenance and machine learning.
  2. IO-Link offers remote configuration of devices, enabling quick and automated change overs on the production line for different batches, reducing change over times and boosting plant productivity.
  3. IO-Link’s automatic parameterization feature simplifies device replacement, reducing unplanned down-time.

Hope this helps boost productivity of your plant!

Rise of the Robots: IO-Link Maximizes Utilization, Saves Time and Money

Manufacturers around the world are buying industrial robots at an incredible pace. In the April 2020 report from Tractia & Statista, “the global market for robots is expected to grow at a compound annual growth rate (CAGR) of around 26 percent to reach just under 210 billion US dollars by 2025.” But are we gaining everything we can to capitalize on this investment when the robots are applied? Robot utilization is a key metric for realizing return-on-investment (ROI). By adding smart devices on and around the robot, we can improve efficiencies, add flexibility, and expand visibility in our robot implementations. To maximize robot utilization and secure a real ROI there are key actions to follow beyond only enabling a robot; these are: embracing the open automation standard IO-Link, implementing smart grippers, and expanding end-effector application possibilities.

In this blog, I will discuss the benefits of implementing IO-Link. Future blog posts will concentrate on the other actions.

Why care about IO-Link?

First, a quick definition. IO-Link is an open standard (IEC 61131-9) that is more than ten years old and supported by close to 300 component suppliers in manufacturing, providing more than 70 automation technologies (figure 1). It works in a point-to-point architecture utilizing a central master with sub-devices that connect directly to the master, very similar to the way USB works in the PC environment. It was designed to be easy to integrate, simple to support, and fast to implement into manufacturing processes.

Figure 1 – The IO-Link consortium has close to 300 companies providing more than 70 automation technologies.

Using standard cordsets and 24Vdc power, IO-Link has been applied as a retrofit on current machines and designed into the newest robotic work cells. Available devices include pneumatic valve manifolds, grippers, smart sensors, I/O hubs, safety I/O, vacuum generators and more. Machine builders and equipment OEMs find that IO-Link saves them dramatically on engineering, building and the commissioning of new machines. Manufacturers find value in the flexibility and diagnostic capabilities of the devices, making it easier to troubleshoot problems and recover more quickly from downtime. With the ability to pre-program device parameters, troublesome complex-device setup can be automated, reducing new machine build times and reducing part replacement times during device failure on the production line.

Capture Data & Control Automation

Figure 2 – With IIoT-ready IO-Link sensors and masters, data can be captured without impacting the automation control.

The final point of value for robotic smart manufacturing is that IO-Link is set up to support applications for the Industrial Internet of Things (IIoT). IO-Link devices are IIoT ready, enabling Industry 4.0 projects and smart factory applications. This is important as predictive maintenance and big-data applications are only possible if we have the capabilities of collecting data from devices in, around and close to the production. As we look to gain more visibility into our processes, the ability to reach deep into your production systems will provide major new insights. By integrating IIoT-ready IO-Link devices into robotic automation applications, we can capture data for future analytics projects while not interrupting the control of the automation processes (figure 2).

Tire Manufacturing – IO-Link is on a Roll

Everyone working in the mobility industry knows that the tire manufacturing process is divided up into five areas throughout a large manufacturing plant.

    1. Mixing
    2. Tire prep
    3. Tire build
    4. Curing and molds
    5. Final inspection

Naturally,  conveyors, material handling, and AGV processes throughout the whole plant.

All of these areas have opportunities for IO-Link components, and there are already some good success stories for some of these processes using IO-Link.

A major opportunity for IO-Link can be found in the curing press area. Typically, a manufacturing plant will have about 75 – 100 dual cavity curing presses, with larger plants having  even more. On these tire curing presses are many inputs and outputs in analog signals. These signals can be comprised of pressure switches, sensors, pneumatic, hydraulic, linear positioning, sensors in safety devices, thermo-couples and RTD, flow and much more.

IO-Link provides the opportunity to have all of those inputs, outputs and analog devices connected directly to an IO-Link master block and hub topography. This makes it not only easier to integrate all of those devices but allows you to easily integrate them into your PLC controls.

Machine builders in this space who have already integrated IO-Linked have discovered how much easier it is to lay out their machine designs, commission the machines, and decrease their costs on machine build time and installations.

Tire manufacturing plants will find that the visual diagnostics on the IO-Link masters and hubs, as well as alarms and bits in their HMIs, will quickly help them troubleshoot device problems. This decreases machine downtime and delivers predictive maintenance capabilities.

Recently a global tire manufacturer getting ready to design the curing presses for a new plant examined the benefits of installing IO-Link and revealed a cost savings of more than $10,000 per press. This opened their eyes to evaluating IO-Link technology even more.

Tire Manufacturing is a perfect environment to present IO-Link products. Many tire plants are looking to upgrade old machines and add new processes, ideal conditions for IO-Link. And all industries are interested in ways to stretch their budget.