Three Things to Know About IO-Link

IO-Link has become synonymous with the term “distributed modular I/O”. We know it is universal, smart, and easy, but what exactly is IO-Link? In a nutshell, by utilizing a standard sensor cable, the IO-Link slave device speaks point to point with an IO-Link master. The IO-Link master then combines the data with other IO-Link slave devices and communicates over an industrial network or backplane to the controller. In other words, it can be compared to a simple USB connection: for the most part, any USB device will work in any USB port, as long as the manufacturers of both devices have played by the rules when making the devices.

With that being said, here are three things to know about IO-Link:

  • Cable Length Cable Type and Length

Cable runs between master and slave can be up to 20 meters in length and typically utilize standard automation cables. Most cables, but not all, are M12 A-coded, unshielded, 3 or 4-conductor DC sensor cables.

  • Star ArchitectureStar Architecture

Since IO-Link utilizes a point-to-point serial communication, Star Topology is the only device architecture that can be constructed.

  • IO-Link PortsPort Class A vs Port Class B Devices

While most devices utilize IO-Link port Class A, output devices like valves are now being offered as IO-Link port Class B. Be sure to know if the master and/or slaves are Class A or Class B type ports. Most Balluff devices are IO-Link port Class A.

To learn more visit balluff.us/iolink

Is IO-Link only for Simplifying Sensor Integration?

PossibilitiesOn several occasions, I was asked what other applications IO-Link is suitable for? Is it only for sensor integration? Well the answer is no! There are several uses for IO-Link and we are just beginning to scratch the surface for what IO-Link can do. In this blog post I will cover at least 7 common uses for IO-Link including sensor integration.
IO-Link in essence provides tremendous flexibility. Each available IO-Link port offers the possibility to connect devices from hundreds of manufacturers to build a resilient distributed modular controls architecture — that is essentially independent of the fieldbus or network. IO-Link is the first standardized sensor/actuator communication protocol as defined in IEC61131-9.

USE-CASE #1: Simplify sensor integration
Multitudes of IO-Link sensors from 100+ manufacturers can be connected using the simple 3-wire M12 prox cables. No shielded cables are required. Additionally, using IO-Link provides a parameterization feature and anti-tampering abilities- on the same 3 wires. The sensor can be configured remotely through a PLC or the controller and all the configuration settings can be stored for re-application when the sensor is replaced. This way, on your dreaded night shift changing complex sensor is just plug-n-play. Recipe changes on the line are a breeze too. For example, if you have an IO-Link color sensor configured to detect a green color and for the next batch you want to start detecting red color- with IO-Link it is simply a matter of sending a parameter for the color sensor – instead of sending a maintenance person to change the settings on the sensor itself — saving valuable time on the line.
color sensors

USE-CASE #2: Simplify analog sensor connections
In one of my previous blogs, “Simplify your existing analog sensor connection”, I detailed how connecting an analog sensor with single or multi-channel analog-to-IO-Link (A/D) converters can eliminate expensive shielded cables and expensive analog cards in the controller rack and avoids all the hassle that comes with the analog sensors.

USE-CASE #3: Simplify RFID communication
IO-Link makes applications with RFID particularly intriguing because it takes all the complexity of the RFID systems out for simple applications such as access control, error-proofing, number plate tracking and so on. In an open port on IO-Link master device you can add read/write or read only RFID heads and start programming. A couple of things to note here is this IO-Link based RFID is geared for small data communication where the data is about 100-200 bytes. Of-course if you are getting into high volume data applications a dedicated RFID is preferred. The applications mentioned above are not data intensive and IO-Link RFID is a perfect solution for it.

USE-CASE #4: Simplify Valve Integration
valve manifoldTypically valve banks from major manufacturers come with a D-sub connection with 25 pins. These 25 wires are now required to be routed back to the controls cabinet, cut, stripped, labeled, crimped and then terminated. The other expensive option is to use a network node on the valve bank itself, which requires routing expensive network cable and power cable to the valve bank. Not to mention the added cost for the network node on the valve bank. Several manufacturers now offer IO-Link on the valve manifold itself simplifying connection to 4-wires and utilizing inexpensive M12 prox cables. If you still have the old D-sub connector, an IO-Link to 25-pin D-sub connectors may be a better solution to simplify the valve bank installation. This way, you can easily retrofit your valve bank to get the enhanced diagnostics with IO-Link without much cost. Using IO-Link valve connectors not only saves time on integration by avoiding the labor associated with wire routing, but it also offers a cost effective solution compared to a network node on the valve manifold. Now you can get multiple valve manifolds on the single network node (used by the IO-Link master) rather than providing a single node for each valve manifold in use.

USE-CASE #5 Simplify Process Visualization
Who would have thought IO-Link can add intelligence to a stack light or status indicator? Well, we did. Balluff introduced an IO-Link based fully programmable LED tower light system to disrupt the status indicator market. The LED tower light, or SmartLight, uses a 3-wire M12 prox cable and offers different modes of operations such as standard stack light mode with up to 5 segments of various color lights to show the status of the system, or as a run-light mode to display particular information about your process such as system is running but soon needs a mechanical or electrical maintenance and this is done by simply changing colors of a running segment or the background segment. Another mode of operation could be a level mode where you can show the progress of process or show the fork-lift operators that the station is running low on parts. Since the Smartlight uses LEDs to show the information, the colors, and the intensity of the light can be programmed. If that is not enough you can also add a buzzer that offers programmable chopped, beep or continuous sound. The Smartlight takes all of the complexity of the stack light and adds more features and functions to upgrade your plant floor.

USE-CASE #6: Non-contact connection of power and data exchange
Several times on assembly lines, a question is how to provide power to the moving pallets to energize the sensors and I/O required for the operation? When multi-pin connectors are used the biggest problem is that the pins break by constantly connecting or disconnecting. Utilizing an inductive coupling device that can enable transfer of power and IO-Link data across an air-gap simplifies the installation and eliminates the unplanned down-time. With IO-Link inductive couplers, up to 32 bytes of data and power can be transferred. Yes you can activate valves over the inductive couplers!  More on inductive coupling can be found on my other series of blogs “Simple Concepts for Complex Automation”

USE-CASE #7: Build flexible high density I/O architectures.
IO PointsHow many I/O points are you hosting today on a single network drop? The typical answer is 16 I/O points. What happens when you need one additional I/O point or the end-user demands 20% additional I/O points on the machine? Until now, you were adding more network or fieldbus nodes and maintaining them. With I/O hubs powered by IO-link on that same M12 4-wire cable, now each network node can host up to 480 I/O points if you use 16 port IO-Link masters. Typically most of our customers use 8-port IO-Link masters and they have the capacity to build up to 240 configurable I/O on a single network drop. Each port on the I/O hub hosts two channels of I/O points with each channel configurable as input or output, as normally open or normally closed. Additionally, you can get diagnostics down to each port about over-current or short-circuit. And the good thing is, each I/O hub can be about 20m away.

In a nutshell, IO-Link can be used for more than just simplifying sensor integration and can help significantly reduce your costs for building flexible resilient controls architectures. Still don’t believe it? Contact us and we can work through your particular architecture to see if IO-Link offers a viable option for you on your next project.

Learn more about our IO-Link solutions at www.balluff.com/io-link

The promise of the Industrial Internet of Things (IIoT)

Things to Avoid and Pursue

There is a long list of activities Control Engineers and Plant Managers avoid like the plague…

  • Modifying PLC code
  • Adding an HMI
  • Modifying HMI screens
  • Adding additional Indicators

On the other side, there is a list of activities they need to do to keep their plant on the forefront of lean manufacturing…

  • Providing real-time operational visibility
  • Adding new manufacturing/process functions
  • Adding/updating Error Proofing devices
  • Providing preventative and predictive maintenance information
Scaling up to IIoT with IO-Link and Balluff's Virtual IP Address Concept
Scaling up to IIoT with IO-Link and Balluff’s Virtual IP Address Concept

Fortunately, the IIoT can help you avoid what you want to avoid and do more of what you need to do. The promise of IIoT can be realized with an IO-Link Architecture featuring Balluff’s Virtual IP address concept. This scalable architecture allows the PLC to do its thing while an independent PC (the one on your desk for example) can access the IO devices directly to get at operational and process data not always available in the PLC.

Learn more at www.balluff.us/io-link.

How Do I Make My Analog Sensor Less Complex?

So, you have a (or many) analog sensor in your application or system and they could be 4-20mA signal or 0-10V or even -10- +10V signal strength. You probably know that installing these specialty sensors takes some effort. You need shielded cables for signal transmission, the sensor probably has some digital interface for set-point settings or configuration. In all, there are probably 6-8 at minimum terminations for this single sensor. Furthermore, these expensive cables need to be routed properly to ensure minimal electromagnetic interference (EMI) on the wire. To make matter more complex, when its time to diagnose problem with the sensor, it is always on the back of your mind that may be the cable is catching some interference and giving improper readings or errors.

shieldedCablesOn the other hand, the cost side also is little tricky. You have the state of the art sensor that requires expensive shielded cable and the expensive analog input card (which generally has 4 channels- even if you use single channel), plus some digital I/O to get this single sensor to communicate to your PLC/PAC or controller. You are absolutely right, that is why people are demanding to have this sensor directly on their network so that it eliminates all the expensive cables and cards and talks directly to the controller on express way– so to speak.

Recently, there has been an explosion of industrial communication networks and fieldbuses. To name a few: EtherNet/IP, DeviceNet, PROFINET, PROFIBUS, CC-Link, CC-Link IE, Powerlink, Sercos, and the list goes on. As a machine builder, you want to be open to any network of customer’s choice. So, if that is the case, having network node on the sensor itself would make that sensor more bulky and expensive than before — but not only that, now the manufacturers have to develop sensor connectivity to ALL the networks and maintain separate inventory of each type. As a machine builder, it does put lot more stress on you as well to maintain different Bills of Materials (BOMs) for different projects – most likely – different sourcing channels and so on.

NetworksSo far what we discussed are two extremes; the way of the past with shielded cables and analog cards, and a wishful future where all devices are on the network. There is a middle ground that bridges yesterday’s method and the wishful future without adding any burden on manufacturers of the sensors or even the machine builders. The solution is IO-Link. IO-Link is the first standard (IEC 61131-9) sensor actuator communication technology. There are over 100+ members in the consortium that produce wide variety of sensors that can communicate over IO-Link.

If a sensor has IO-Link communication, denoted by  io-linklogo, then you can connect a standard M12 prox cable — let me stress– UNSHIELDED, to connect the sensor to the IO-Link port on the IO-Link master device. That’s it! No need to terminate connections, or buy expensive hardware. The IO-Link master device typically has 4, 8 or 16 ports to connect various IO-Link devices including I/O hubs, RFID, Valve connectors and more. (see picture below)

DistModIO

All signal communication and configuration now occurs on standard 3 conductor cable that you are currently using for your discrete sensors. The IO-Link master in turn acts as a gateway to the network. So, the IO-Link master sits on the network or fieldbus and collects all the sensors or discrete I/O information from devices and sends it to the controller or the PLC of the customer choice.

When your customer demands a different network or the fieldbus, the only thing that changes in your question is the master that talks to a different protocol.

In my next blog we will discuss how you can eliminate shielded cables and expensive analog cards for your existing analog sensor. Let me give you a hint– again the solution is with IO-Link.

You can learn more about IO-Link at www.balluff.us.

When to use IO-Link RFID

IO-Link logoAt this point it is pretty clear that RFID is a fairly simple identification solution that involves a tag, antenna, and processor. The tag holds the information that is critical to the application. That information could be a very brief identifying number, sometimes called a license plate, and usually consists of 4 to 12 Bytes of data. Or, the application may require the tag to hold all the information about the product being manufactured such as build data, process data, or lineage data. In this case, there are tags with up to 128 Kilobytes of available storage. The scenarios above help to answer the question: “when do I use IO-Link RFID?”

Simply put, IO-Link makes life on the manufacturing floor much easier. It eliminates the mess in the cabinet, it is plug and play, it allows connection to any major controller, etc. etc. etc. So, why not just do away with everything not IO-Link and call it a day? For RFID there is 1 major question that needs to be answered to determine whether or not IO-Link is the right solution: How much data needs to be read from the tag?

IO-link specializes in transferring smaller amounts of data. When required to transfer large amounts the speed is greatly reduced. Here is a very simple way to look at it: IO-Link RFID comes in two different versions- 10Bytes or 32Bytes. The 10 Bytes or 32 Bytes refer to the size of the buffer or container that transfers the data. Imagine this as two semi-trucks carrying a load in a trailer (buffer). Of course, the 32 Byte trailer can carry a larger load (Data) than the 10Byte trailer. Therefore, we can conclude that the 10Byte trailer has to make more trips to carry larger amounts of data. More trips take more time therefore slowing down the process. If there are only 8Bytes of data that need to be read from the tag then the 10Byte version is fine, but if there are 28 bytes then it makes sense to us the 32 Byte version. However, as mentioned above there are applications where the tag may hold up to 8KB, 32KB, or even 128KB of data and IO-Link should not be considered. As a general rule IO-link should not be used to read anything over 96 Bytes due to speed being greatly reduced.

Need For Speed?

As a rule of thumb it takes about .2 seconds for IO-Link RFID readers to read 16Bytes of data and about .5 seconds to read 96Bytes. Reading anything above 96Bytes increases the read time dramatically. As a comparison, the latest and greatest Balluff RFID processor, the BIS V can read 256Bytes of data in about .2 seconds.

Ultimately, the amount of data that needs to be read from the tag and the time required to read that data should be the deciding factors of whether or not IO-Link RFID is right for the job or not.

To learn more about IO-Link visit www.balluff.us

Distributed Modular I/O Demo on Demand!

Everyone likes things on demand right?  Movies, TV shows, chocolate, you name it.  My good friend, John Harmon, has prepared a YouTube video so that you have at your fingertips an on-demand presentation on Distributed Modular I/O.  It is a great overview of the available functionality of Distributed Modular I/O and what kinds of control products that are available utilizing this technology.  I realize the video is seven and a half minutes, which is pretty long for a web video, but I think he does an excellent job of keeping your attention and demonstrating the value of this technology.  Grab a soda and your favorite chocolate bar, put your phone on silent, and hit play on this excellent presentation.

Continue reading “Distributed Modular I/O Demo on Demand!”

Valve Manifolds on Ethernet for Cheap!

Valve manifolds, or islands or banks, are used by many automation engineers in their machine design. They are a great way to easily implement a large number of pneumatic motion applications while keeping the air infrastructure minimal.  Recent demand in the market has driven manifold manufacturers to reluctantly embed network interfaces and remote I/O into their products.   Customers tell me while manufacturer’s expertise may lie with the pneumatic side of the product; there is usually less knowledge with-in their organizations to work on the Ethernet side of the product.

Continue reading “Valve Manifolds on Ethernet for Cheap!”