What Interoperability Means for the Internet of Things

By Nathan Rockershousen, Technical Writer

The Internet of Things (IoT) is reliant upon connection, making communication one of the most rudimentary functions of internet-enabled technology. Interoperability opens up endless opportunities for IoT devices as it ensures that devices will be able to communicate with each other and store data in a central location. The IoT will be able to fulfil its promises of convenience and functionality if multiple devices can be controlled simultaneously while being able to communicate and transfer data with each other.

A majority of the companies that are manufacturing IoT technology are trying to create platforms and devices that will be accepted as the “industry leading solution.” However, this culture within the IoT industry has led to a large assortment of devices that have to be controlled as separate entities and from different apps. The fact of the matter is that consumers simply don’t want to have 50 different devices, each with their own app, that operate independently of each other. The growth of the industry will be limited until manufacturers begin to collaborate in developing devices that will work together within the same network.

Manufacturers clearly understand that interoperability is a necessity for the IoT to continue to grow. So why hasn’t a standardized control system been created? The answer is simple: money and brand recognition. Each company wants to be the one that develops the ultimate “hub” for controlling IoT technology as it will come with a major payout. This isn’t necessarily a bad thing; it just means it will take more time to reach seamless interoperability than it would if there were more collaborative efforts. That being said, there are still some open-source initiatives to create interoperability that have shown signs of promise such as Qualcomm’s AllSeen Alliance.

When it comes to the individual corporations that are trying to create hubs for controlling smart technology, it appears that Apple is on the verge of creating total interoperability for HomeKit products. The upgraded Apple operating system, iOS10, has transformed the way HomeKit is used with its addition of the Home app. This app allows for any HomeKit device to be controlled from a central location. This means that instead of going to an app for each manufacturer, all devices can be controlled in the hub Apple has integrated within their new operating system. Companies like Google and Microsoft have also created similar smart home platforms, but they don’t quite offer this level of interoperability and don’t seem to have as much traction in the consumer world. These developments in HomeKit are great strides in achieving interoperability within the IoT.

Even though HomeKit has achieved a previously unseen level of interoperability, it still isn’t quite what consumers want in terms of creating a smart home that is completely connected. This is because HomeKit products are the only products that can communicate and operate within this network, thus limiting the device integration to Apple approved devices. This isn’t a bad thing for Apple because many other tech giants are trying to create this same level of interoperability for their respective smart home platforms. At this point in time, this segregated version of interoperability is the best consumers will get until these large corporations put their differences aside.

The current trends within the IoT industry are unlikely to change anytime soon due to the fact that smart home technology is still in the late stages of its infancy. As technology becomes more advanced and more efficient, consumers will begin to demand networks that are more connected, with devices that are able to communicate and operate in harmony. The interoperability provided in Apple HomeKit is a significant advancement from previous systems and is an innovative solution at this point in time. It will be interesting to see if large IoT businesses will be willing to work together in an effort to create a centralized hub that can control and communicate with any type of smart device.

2016 Entrepreneurial Excellence Awards honorees

Mike Justice, President and Founder of Grid Connect, was recently honored with the IMG_0868Lifetime Achievement Award by the Daily Herald Business Ledger.

Mike Justice is a serial entrepreneur, industrial networking expert, and has successfully built and sold several technology ventures.

In 2003, Justice started Grid Connect inviting many employees from a previous company in which he was involved to join his new venture.

Grid Connect is a rapidly growing manufacturer and distributor of networking products and wireless sensors with more than $13 million in sales worldwide.

Culture and professional growth are two of Justice’s key elements at Grid Connect. Every Wednesday employees are treated to free lunches, complimentary massages on Thursdays and frequent table tennis matches at lunchtime.

Grid Connect has been named as a “Best Place to Work in Illinois” for the last two years and named a “Top 10 Small Business to Work for in Illinois.”

Justice is also locally involved with Naperville North High School’s Robotics Team, where he helps develop and sponsor young engineers.

Read more about the other nominees, here: http://www.dailyherald.com/article/20161010/business/161019928/

IPv6 and The Internet of Things

By Nathan Rockershousen, Technical Writer

A majority of the tech industry has come to accept that the Internet of Things (IoT) will increase in size by the year 2020, enabling around 30 billion internet-connected devices. Internet Protocol Version 4 (IPv4) was the first internet protocol to be released for public use. When it was released, it only allocated enough address spaces to accommodate for just over 4 billion devices, which is clearly not even close to enough space at this point in time. Internet Protocol Version 6 (IPv6), which is the most recent internet protocol, is the perfect solution for the IoT as it extends the number of address spaces to roughly 340 undecillion.

The IPv6 can essentially provide every person on Earth with around 4,000 usable IP addresses, which is more than enough space to sustain the expected IoT growth. Due to the limited size of the IPv4, implementing IPv6 as the new standard for internet connectivity is inevitable. When IPv4 began to run out of address space, Network Address Translation (NAT) was developed to enable different devices to share the same public IP address. At the time, this was a very innovative solution that compensated for the unexpected expansion of the internet. However, many devices that are being developed today utilize an IPv6 address space. Even though converting any IPv4 addresses to IPv6 may be cumbersome, it is only a matter of time before IPv6 is universally accepted, rendering IPv4 infrastructures completely useless.

What does this have to do with the IoT? The most important thing to consider is that upgrading from IPv4 to IPv6 will require end-to-end encryption and a stronger authentication process. This is because using NAT creates a middleman in the device communication, removing the ability to have more secure machine to machine (M2M) communication. IoT devices are heavily reliant upon robust and secure communication as the data collected by device sensors can include sensitive information. IPv6 will enable safe M2M communication and allow for the IoT to continue to expand at its expected, exponential rate. There can still be some security risks with IPv6, but it is a significant advancement in comparison to IPv4.

Security aside, IPv6 could be the solution for multi-protocol interoperability between different devices. This is due to the fact that it includes a very large address space, allowing for the internet to be extended to any device. IPv6 utilizes auto-configuration, which is used to establish a link-local address. It can then use its Neighbor Discovery Protocol (NDP) to check if the address is unused and unique before it saves it. This is a major upgrade for the IoT because IPv6 completes its address conflict detection before actually using the address itself, which IPv4 did not do.

When it comes to things such as mobility and scalability, IPv6 is well equipped to handle the plethora of IoT devices that will soon be creating networks within homes and cities. This upgraded internet protocol brings more functionality and more security than IPv4 could offer, while ensure every device will have a unique IP address. As the IoT world continues to expand at such a rapid pace, its dependency on IPv6 is an unavoidable step in creating seamless device interoperability and communication.

The Internet of Things and Bluetooth

By Nathan Rockershousen, Technical Writer

Despite its name, the Internet of Things (IoT) is not constricted to purely internet-based connectivity. In fact, Bluetooth Low Energy (BLE) solutions are increasing the functionality of IoT devices more successfully than via the internet, creating a more reliable framework for further connectivity. BLE technology will enhance and optimize the overarching operability of smart home devices by creating faster communication speeds and extending signal range.

Even though using the internet to connect devices works very well, it can have inconsistencies in its connection and shorten the battery life of various devices. These issues can be resolved through the use of BLE technology. Using BLE in IoT technology will allow devices to operate for extended periods of time on small power sources. In a readwrite article, it was stated that the new updates to Bluetooth technology made it possible for a coin-cell battery to last for several months, or even several years. Implementing Bluetooth technology within different IoT devices will help make managing a smart home a very energy efficient process.

The improved functionality of the IoT with the use of BLE goes far beyond simply saving power. BLE has the ability to extend the range of connection between devices by nearly four times that of a Wi-Fi network. This makes it a more reliable method for connecting numerous smart devices throughout a home environment. Not only is there a further range, but the communication speeds are revamped and much more capable to fulfill the demands of the always on and always communicating IoT devices.

Smart devices will be able to take full advantage of increased communication speeds and range due to the fact that BLE utilizes mesh networking. This is a network topology that allows for each device to be fully connected to each other within a network, allowing each node to assist in data distribution. The consumer benefit of mesh networking is explained by NXP; “Applications for Bluetooth mesh networks include those found in most every consumer’s home: door locks, lights, HVAC systems, and white goods (washers, dryers, refrigerators, and so on).” A mesh network is reliable for maintaining a smart home environment because individual devices can still communicate if one device runs out of power or is disconnected.

An increasing amount of manufacturers are beginning to integrate Bluetooth technology within their IoT technology. BLE will improve the overall functionality of the IoT and aid in establishing much more sturdy networks that will sustain the operation of numerous devices. This will help consumers create more efficient and powerful smart home environments.

Humble Beginnings of the IoT

The Internet of Things (IoT), that has been portrayed as an impending revolution, is not a new concept, but is the culmination from many years of connecting objects through computer networks. Kevin Ashton didn’t coin the phrase we use today until 1999 (while referring to RFID tags in supply chains), but the idea that he was employing came about earlier in the 90s when machine-to-machine (M2M) industrial solutions offered closed networks for device communication. Although these types of connections are not new to the tech world, they have only recently gained more ground in potential applicability.

This past October, the Internet Society put out an IoT overview and marked a number of key trends that have sparked the recent interest and excitement regarding connected devices. The pervasiveness of cheap connectivity has dramatically increased over the past few years, which is visible in one way because of the ubiquity of home Wi-Fi networks. In addition, the widespread adoption of IP-based networking creates an avenue for interoperability between devices.

Advances in circuit development and its miniaturization have also drastically changed the way we think about connectivity. The smart phones that many of us have in our pockets possess the processing power which surpasses some of the supercomputers of the 90s. Implementing internet connectivity into a device is drastically more advanced compared to when Kevin Aston first praised the possibilities of RFID and can be accomplished in much more diverse applications.

Finally, the most recent developments in data analytics and cloud computing have boosted the excitement to the point it’s at today: with hundreds of articles postulating the potential use-cases and applicability of the IoT. These movements really allow for the data sharing capabilities that enables a product to be “smart” and establish the support system for powerful third-party developers.

While it is exciting to visualize what the IoT will look like when it finally arrives, it’s helpful to look back a little and see how far we’ve come already. The integration of the internet into our daily lives has been an ongoing process for many years, and a lot of the benefits of these trends are soon to become a reality.

For more information, check out the Internet Societies’ overview: http://bit.ly/1XO2YGf

IoT: Converging IT and OT

By Nathan Rockershousen, Technical Writer

The continuously expanding network of internet-enabled smart technology is transforming the current framework that constitutes the Internet of Things (IoT). Historically, Information Technology (IT) and Operational Technology (OT) have been two completely separate and distinct domains. The importance of physical equipment for monitoring and detecting change in industrial processes through OT has never been truly connected with the processes of electronic data exchange found in IT. However, the integration of wireless sensors into IoT technology is altering the infrastructure of traditional industrial processes. The convergence of IT and OT is an inevitable and necessary step in unleashing the true power of large-scale connectivity via the IoT.

The vast assortment of physical objects being connected to the internet provides manufacturers with the ability to collect and analyze data instantaneously. These networks of devices generate a plethora of data, allowing for the creation of intelligent and immediate solutions. This process is where the lines begin to blur regarding the various IT and OT processes. Traditionally OT infrastructure would require those in charge of operating and maintaining a device to physically process its data in the field. The wide-spread acceptance of gathering data via the internet has enabled workers to access any needed operational data, allowing for analysis and monitoring without having to waste more human resources.

The rapid and continuous growth of the IoT is making the integration of IT and OT environments an inevitable repercussion of increased connectivity between internet-enabled devices. The fundamental technology (software, platforms, etc.) behind OT systems are adapting to operate on a similar level to IT systems. The inherent similarities between modern OT and IT will make it easier to manage an integrated system as opposed to two separate entities. Gartner, which is an IT research company, stated “A shared set of standards and platforms across IT and OT will reduce costs in many areas of software management, and reduced risks come from reducing malware intrusion and internal errors” (Gartner). Efficiency within a company will see an exponential increase with the convergence of IT and OT.

Improving efficiency is only one of the many benefits of implementing an integration system between IT and OT systems. The convergence between these two fields will provide businesses with more information to make smarter decisions in terms of business processes. The integration of IT and OT will enable further analysis of products through data, which will lead to performance improvements that can increase the satisfaction of consumers. Being able to coordinate efforts between IT and OT within an organization is a cost-efficient method in reducing missteps in decision-making.

Top suburban entrepreneurs honored at Business Ledger event

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Last night was dedicated to risk taking and overcoming failure as 19 local entrepreneurs were honored during the 17th Annual Entrepreneurial Excellence Awards, hosted by the Business Ledger and its sponsoring partners. Mike Justice, founder, president, and CEO of Grid Connect was honored with the Lifetime Achievement Award.

Read more about some of the top entrepreneurs in the Chicago suburbs here: http://www.dailyherald.com/article/20160915/business/160919140/

 

 

 

Simplifying IoT: Connecting, Commissioning, and Controlling with Near Field Communication (NFC)

By Nathan Rockershousen, Technical Writer

The Internet of Things (IoT) is in the process of transforming the way we live our lives by improving the quality of life with technological advancements in efficiency and safety. Consumers will be among the biggest beneficiaries as the home environment is one of the main platforms for the advancement of smart ecosystems. The habits of individual consumers will be detected by devices within smart home ecosystems and then that information will be used to optimize the environment. The connectivity of the IoT will enable the seamless communication among devices. Near Field Communication (NFC) can be used to help developers utilize internet-enabled devices in an effort to maximize the benefits of the IoT in daily life.

It is evident that NFC will be beneficial for smart home devices as nearly 40 billion connected devices are expected to be in use by 2020. NFC provides a simply solution for connecting IoT devices to a network. Any device that is lacking a quality user interface (UI) can be given user-friendly controls with a single tap via NFC. In addition to its ease of use, other benefits include explicit interaction through close proximity interactions, read and write capabilities, and communication with devices that are powered down. NFC is a low cost and low energy solution that will enhance the IoT experience.

Setting up networks of IoT devices clearly has several benefits, but enabling a connected smart home does pose some challenges. A pressing challenge is the difficulty of adding and removing devices within a network. The ability to manage devices can often be difficult when dealing with headless devices that don’t have a built-in UIs. There isn’t really a single way to setup various devices within a smart home environment as users are typically required to follow manufacturer-specific commissioning methods. NFC can be used to resolve these issues and improve the overall user experience.

There are many other challenges that are facing the IoT. However, NFC can offer solutions to some of the following concerns:

Commissioning Devices: As mentioned before, there isn’t a standard protocol in terms of the commissioning process for IoT devices. Users are confronted with too many different methods for adding devices to a network, especially when there are no UIs available. NFC uses a single tap, or proximity to commission a device, thus creating a standardized mechanism for adding devices to a network.

NFC-Based Wi-Fi/Bluetooth Pairing: Most IoT devices connect to a network via Wi-Fi or Bluetooth within a smart home environment, making it more important than ever that they operate with comparable efficiency. In terms of Bluetooth, the NFC Forum and Bluetooth SIG have collaborated to speed up the Bluetooth pairing process. This means that the very slow and time consuming process of device discovery and paring will be eliminated by using the NFC tap to enable an instant and secure connection. The NFC Forum also has been working with the Wi-Fi Alliance to make it easier to connect to wireless networks. Once the user taps the NFC device to the NFC tag for their Wi-Fi network, the device will configure itself and instantly connect without the user having to find the network name (SSID) or manually enter a password.

Headless Device Commissioning: Devices that don’t have a UI don’t have an easy way to add them to a network. Tapping these headless devices against an NFC tag with the networking key built-in will remove the headache of commissioning these devices. NFC is used to establish a secure and quick connection and then can erase the network key from the tag to protect it from being accessed by an unauthorized person.

Controlling a Device with No User Interface: There are a variety of smart devices such as light bulbs, environmental sensors, in-wall outlets, and more, that don’t include an integrated visual display. Even though Wi-Fi and Bluetooth can provide some IoT interactivity, there are still several issues when setting up and configuring devices. NFC offers a very simple and secure method for controlling IoT devices that don’t include a UI. Input interactions (network provisioning and configuration) and output interactions (reporting information and diagnostics) are enabled via NFC.

Access Control for the Smart Home: Environments such as condominiums and high-end apartments have multiple families living in them, which usually requires a massive amount of mechanical keys in order for everyone to enter their homes. Mechanical keys are expensive, time consuming to distribute, and can easily be copied. NFC offers a solution by giving property managers the ability to give tenants a smart card or mobile application to access their homes. Keys can be sent to friends and family members with no cost, and a record will be kept of who enters and exits the home. NFC technology will provide a secure, cost effective, and flexible rekeying solution for property managers.

Many of the current problems facing the IoT in terms of user-friendliness and accessibility will be resolved with NFC. The implementation of NFC can unlock the true power of a large assortment of IoT devices within a smart home ecosystem. NFC technology can enhance the user experience in a secure and flexible manner at a very affordable price. The potential impact that NFC will have on the IoT is widely recognized within the NFC Forum and the IoT SIG.

How Time-Sensitive Networking Enables the IIoT

The world’s first time-sensitive networking (TSN) testbed is being developed in a collaborative effort to change network infrastructure so that it will enhance the Industrial Internet of Things (IIoT). As this develops, it is essential that Industry 4.0. Machine designers, builders, and users have reliable and secure access to smart edge devices. This will force the current, standard network technologies to transform in an effort to meet the requirements of the next generation of industrial systems.

The testbed itself was designed to assist in creating a new wave of innovative technologies, products, applications, and services for the industrial internet market. The Industrial Internet Consortium (IIC), comprised of the corporations developing the testbed, are attempting to create a TSN in an “ecosystem of manufacturing applications,” which is based off of new Ethernet IEEE 802 standards. The goal of the testbed is to provide insight on the security of a TSN as well as highlight its real-time capabilities through the use of standard and converged Ethernet.

In order for TSNs to be taken seriously, it will be crucial that there are sufficient security measures utilized in order to protect the safety of IIoT users. It is essential that the TSN security is integrated as a layered system, meaning security is implemented throughout the network, because simply adding security as an additional feature at the end of development (air-gap security) leaves the network vulnerable as it is only a perimeter-based measure of defense. One beneficial aspect of time-sensitive networking is its ability to determine the exact instance data was sent and when it is supposed to arrive; if anyone intercepts packets of data it will be easy to tell. That being said, TSNs require a central management aspect that have the power to alter entire networks, which could be a challenge in terms of developing security.

The use of deterministic Ethernet will alter the various safety systems for TSNs by allowing messages to be scheduled from safety applications in order to provide high availability for safety systems. The real-time, synchronous mechanisms of the deterministic Ethernet will enable the connection of more devices and more machines, creating a powerful and integrated IIoT. Mike Justice, president of Grid Connect, believes that its use as a control network has the potential to replace other existing networks such as Profibus and DeviceNet.

As the real-time capabilities of deterministic Ethernet continue to develop, there will be several applications that will benefit from the use of a TSN. Machine-to-machine communication would improve as it needs to operate with low latency and high synchronization. Safety-based communications could access data more efficiently as it is currently mostly done through hardwiring. General motion and robot controls would improve as accessing data through standard communication could be done with ease. Essentially any latency-sensitive application would be much improved through the use of a TSN.

Another interesting application of a TSN can be observed through cloud and edge computing as they provide an infrastructure that will improve the functionality IoT technology. The use of deterministic Ethernet through TSNs could theoretically allow for machine control to be executed within a cloud environment, but there isn’t much room for error regarding latency in communication. Even though consumer and industrial applications of cloud-based machine control have different demands in terms of real-time dependency and data consumption, they are still in the foreseeable future if network stability can be established. Private, local clouds have had success in controlling machines, but large public clouds are more concerning with problems such as technical issues, data confidentiality, and security.

Time-sensitive networking is a feasible option for advancing the IIoT as long as it delivers on its promises of speed and security. It will be a major improvement to converge from information technology (IT) to operational technology (OT) in regards to the security and integration of cloud services. Justice states that “The controls industry is conservative and will follow the IT market in a few years after security issues are well-addressed.” The ability of TSNs to connect machines to the cloud and create real-time data messaging and analytics will improve the overall functionality of the IIoT.

 

Read more at: https://www.controldesign.com/articles/2016/how-time-sensitive-networking-enables-the-iiot/?start=4

PROFIBUS Troubleshooting Tool Demonstration

Hardware Setup (0:00):

This is a brief tutorial on how to operate the Procentec PROFIBUS Troubleshooting Toolkit Ultra Plus. For this tutorial, the PROFIBUS Troubleshooting Toolkit Ultra Plus is used. The PROFIBUS Training Kit will also be utilized; this is used for our troubleshooting and maintenance training using the ProfiTrace tools. In the PROFIBUS Training Kit, there is a PLC in the bottom of the case as well as five devices in the inner lid of the case. The last thing we will use is a Windows PC that is running ProfiTrace software.

Inside the tool kit, there is a ProfiCore Ultra, which is the black hardware module. This is the only piece of hardware needed. There are a couple of cables included to help interface this hardware to a PROFIBUS network. The tool kit also comes with a tap cable that connects to the ProfiCore Ultra. In addition to this, there is a USB cable that connects from the other side of the ProfiCore Ultra into a PC or laptop. The last thing included in the training kit is a user’s manual that explains how to use the software.

In order to connect the ProfiCore Ultra to a PROFIBUS instillation, attach the tap cable to the ProfiCore Ultra. Then take the USB cable and plug it into the other side of the ProfiCore Ultra, which will then be plugged into a PC or laptop. Once this is set up, simply take the tap connector and put it on the back of an existing connector on the instillation. In our example, the existing connector is a piggyback (PG) connector attached to the cable coming out of the PLC. Attach the ProfiCore Ultra to the back of that connector. In this case, we want to make sure that the terminating resistor is in the off position.

 

Software Setup (1:50):

At this point, the ProfiCore Ultra should be connected to the training kit and the ProfiTrace 2 software is ready to launch. On the computer being used, go to “Programs,” then select “ProfiTrace V2.7,” which is the latest version. Once the options within this folder are available, select “ProfiTrace V2.7” again. Do NOT select the one that says “ProfiTrace V2.7 for COMbricks,” it is for a different product. The blue start screen for ProfiTrace 2 will launch once it is clicked and it will then automatically redirect to the main screen for ProfiTrace. Across the top of the screen, there will be the typical drop down menu that is in most Windows applications. The buttons and screens specific to ProfiTrace can be found directly underneath this.

ProfiTrace has several optional components in the software. However, every package includes the main “ProfiTrace” page. Across the top of the screen the different optional components can be found. Another included component is the tab called “Network Manager.” “ScopeWare” and “Bar Graph” are sold as a single license together. Other optional components include “Topology Scan” and “ProfiCaptain.” The PROFIBUS Troubleshooting Toolkit Ultra Plus being used for this tutorial does not include ProfiCaptain, so it will not be covered in this walk-through.
Using ProfiTrace Software (3:28):

For now, stay on the main ProfiTrace page that is included in every kit that Grid Connect sells. To begin, click on the button that says “Init ProfiCore Ultra.” It will begin to initialize the ProfiCore Ultra, essentially it is checking the firmware that is loaded in the Ultra to make sure it is the latest firmware. Then it will begin to check the baudrate of the instillation. Once this is complete, there will be five boxes within the main matrix (grid) on the screen. These boxes will be green with a blue number in the center. There will also be a box with a white background and the number “2” in red. The matrix is what is known as the live list, which shows the addresses that are available in PROFIBUS. This means that we have PROFIBUS address 0 (Row 0, Column 0), located in the top left corner of the matrix, all the way down to PROFIBUS address 126 (Row 120, Column 6), located in the bottom right of the matrix. This is the maximum number of addresses available, according to the PROFIBUS specification.

Anywhere ProfiTrace is listening to the bus or anywhere it senses a device communicating, it will put it in the box that represents whatever address it is communicating from. In this case we have the five slave devices (located in the lid of the training kit) that were mentioned earlier in this tutorial. It is also important to note that the red “2” represents the master or PLC. The devices that are marked with the green box means that they are in normal data exchange with the master. Basically the master is writing outputs and reading inputs in a cyclical fashion to these devices and they are all in data exchange. This is a live list, meaning the things we see on the screen are the things actually happening right now.

To see how this works, we can simply turn off one of the devices in the training kit. We have small on/off switches to make this easy. Once the device is off, there will be a blinking red light in the top left corner of the device’s address box. The phrase “Phoenix Contact” will then appear on the screen when the box turns from green to yellow. The yellow color means that the device was on the bus communicating, but then it suddenly stopped, which makes sense because we turned the power off. Essentially the device is no longer communicating with the master, which ProfiTrace senses when it changes the background to yellow. Clicking on “Phoenix Contact” within the box will provide information in the section on the left of the screen titled, “Info Panel.” This is next to the live list, which is indicated with a heart image, that includes the matrix we worked with moments ago.

In terms of the error that occurred, the red blinking light in the top left corner of the box indicated that the device was sending a diagnostic message. Essentially what happened was that the Phoenix I/O block that we have in our training kit has some capacitive power that remains if it loses power. This allows it to last just long enough so that it can tell the PLC that it has lost power. In the Info Panel, it will say something that says “low voltage sensor supply US 1.” Basically it noted that it lost power, so it raised a diagnostic flag. In its messages, the master saw the diagnostic flag and asked for the diagnostic message. Then the device didn’t have enough power to keep living, so it dropped off the bus. This is what created what we now see before us.

Why did the Phoenix Contact suddenly appear? ProfiTrace is listening to the bus. Every device manufacturer assigns something that is called an “ident number” for each one of their types of devices. An ident number is just a way to identify each device of a particular type. An example would be a Siemens ET200S, each one of these devices has the same ident number. Each manufacturer creates a file called a GSD file, which contains all information about the device, how many words of input and output it has, information about what types of diagnostic messages it supports, information about the manufacturers, and so on. When a diagnostic message is generated, the ident number is included during that time. Once ProfiTrace sees the ident number, it will go look in its folder of GSD files to see if it has one that matches that ident number. Then it can know what device that was that just got its power turned off. When we plugged it in, the devices were all in data exchange when ProfiTrace started, so there wasn’t an ident number. ProfiTrace didn’t know anything except the address the devices were transmitting their messages to and from. It could not tell us that at that point it was a Phoenix Contact, it could only tell us it was a Phoenix Contact when it saw the ident number.

So now that we know this information, we can switch the device back on and simultaneously see the device turn green again. At the bottom of the screen, there is an isolated green box, which is a special device in our training kit from Acme corporation. Essentially it is a device that Procentec created for training purposes. For our troubleshooting classes, it is a way to let students discover that this device has power that follows another device when it powers off. It had a little power glitch from the other device. During that time, we saw the ident number for our fake device (Acme device) and were able to look up the GSD file and so on.

If we turn off any other device there will be similar results as the color changes from green to yellow. The Siemens works exactly the same as the Phoenix Contact. When we turn off the Brad device, the color will change yellow. However, there is no diagnostic at the beginning so this device is unidentifiable; this is because the device doesn’t have capacitive power. When it is turned back on and it starts back up as part of the initialization process, it provides its ident number, allowing the user to know what it was when it came back on the bus. The last device on the network we are using is the Turck. This device does have a little capacitive power and was able to send the diagnostic message before it totally lost power.

Now we can see the five devices in green with the device names in blue. As stated previously, if the names are clicked individually, the information about them can be accessed in the Info Panel.

Accesses GSD Files (11:00):

The next important thing to cover is the fact that there is a place where the GSD files are saved. In the “Settings” menu at the top of the screen, go to “Preferences.” At the bottom of the “General” tab in preferences, there is a section labeled “GSD directory locations.” This will provide the directory where the user can say where their GSD files are. This allows the user to add their own files. Let’s say that the user owned Step 7 software. They could use those GSD files to point ProfiTrace to their directory. Another option is to use the standard directory that is under the ProfiTrace software in “Program Files,” which is part of the Windows C-Drive.
Checking Device Statistics (11:40):

When looking at the live list on the main screen, the user is able to see real time updates of what is going on. If the user had just walked up to the instillation and saw that all of the devices are green, they would assume that there is nothing wrong with the instillation. In reality, they would be seeing a real time representation of what is going on right now. The user has no idea what happened five minutes ago, or even an hour ago by looking at the live list screen. Fortunately, ProfiTrace includes a statistics function. There are little tabs across the top of the matrix that change what is shown in the main window. For this tutorial, we have been in the live list tab. For this purpose, move over to the tab that is titled “Station statistics view” and click on it.

From this new tab, the user can see something called “Syncs” that is going on. The syncs statistics are measured. The boxes show how many times each of the devices took a sync message. Sync messages are sent out by the master whenever a device drops off of the bus and it is trying to bring it back. This is essentially an “are you there” message. Every time the master is attempting to talk to a device that is missing, it would just send a sync message instead of its usual write outputs and read inputs. Basically the device says “are you there?” When the device gets power back or is returned to the bus, it will answer and the master will put it back into data exchange on the next cycle. If there are sync messages, it lets the user know if there have been problems on their network because it means that a device has been missing. The Phoenix Contact that was turned off at address 15 in our demonstration was off for quite a bit longer than the other devices. In the few minutes it was off, it recorded 68,000 sync messages, which is substantially larger than the others.

At the top of the matrix, there is a drop down menu that is titled “selected statistic.” A variety of different statistics, including syncs, can be accessed from this menu. Let’s take a look at the “station lost” statistic, which is a little simpler than the sync statistic. This statistic simply shows the user how many times the device dropped off of the bus. There are about 20 statistical variants that are recorded by ProfiTrace. As long as it is plugged in and active, it will be recording these statistics so the user can look at things such as the slowest/fastest data exchange interval, I/O size, diagnostic messages requested by the master, and lots of other great stats. However, the main ones are at the top of the drop down list.
Messages (14:45):

Another thing that can be done with ProfiTrace is to look at the messages that are being sent on the bus. To access these messages, click on the “Messages” tab that is above the matrix. This will be in line with the live list and statistic tabs that we have previously used. The next think to do is click on “Start message recording,” which means that ProfiTrace is going to start recording the messages that are on the bus. One thing to notice is the blue line advancing across the bottom of the window. This is representative of the memory filling up with the messages that are being recorded. It fills up relatively quickly, so it won’t be long before the blue line reaches the end and it will stop recording messages. The user has the option to set the program to record to the last amount of messages rotating out of the buffer so they can see the latest messages. However, that may not be very useful if the user actually had a problem. This is because the messages that were going on at the time of the problem will be long gone by the time the user looks at the messages tab. For the purpose of this tutorial, click the message recording button again to turn it off.

We advise people to set up what is called a record trigger. There is a button just to the left of the start message recording button we referenced earlier. We can then go to the record trigger button and click on the “Enabled” box in the setup page. After this we can click on “Re-trigger,” which means if this event that we are triggering on happens again, it will record messages again. Then we can say for example, “let’s record 15 messages before the trigger, and 15 messages after the trigger.” This information can be entered on the setup trigger page directly below the enabled and re-trigger options. After all of this information is entered, click on the button on the right side of this menu that says “setup trigger.” In this case, let’s just say when the station goes lost, we want to record. Click “okay” to return to the initial trigger page, then click “okay” once more to return to the main window. Now we can click the start message recording button as we did earlier. This will clear out the buffer as it is waiting for a trigger event to happen.

To show what would happen in that event, we will power off the Phoenix device again. In a matter of seconds there will now be 15 messages before and after the event. The event being the one that is marked in the red text with the word “lost” after the last repeat message. When a device drops off of the bus, there is a bus parameter in PROFIBUS that says how many times the user would like to send a message if a device fails to respond, which is called a retry. Normally, it is defaulted to one, but we usually recommend a number a little bit higher than that. In our version, it is set to five. It really depends on the user’s PLC program, how fast it has to run, and things of that nature. If repeats are set to greater than one, it can help avoid some nuisance problems in PROFIBUS. In this case, it is set to five so the master sent the message five times after the Phoenix dropped off of the bus and on the fifth time the master said “okay you are lost.” The master would then start to send a sync message to that device on the next cycle.

If we were to cause another event, we could turn off the Siemens. If we scroll down in the message file, we can see the sync message from the device in address fifteen that was turned off. The messages are repeated to our Acme device, then the message is sent to the Siemens. There were actually three events in our situation because the Acme device follows the Siemens. In the column labeled “Service,” the user can see that the data exchange going on with the device. In the column labeled “Addr,” the user can see who sent the message and who received it. In this case, there is a message from address 2 (master) to the device in address 36. On the right in the column labeled “Data,” the 6A in hex is the data that was sent. It comes back as a bunch of zeros which is represented with the 36 coming back to the 2. Essentially it shows the write outputs followed by the read inputs all the way down the column. If everything is working fine it would do this over and over again for all five devices. In this case, we have lost one, so now it is sending a sync to that Siemens every time it’s his turn to respond in the cycle. Messages can essentially help the user figure out what is going on within their network.
ScopeWare (19:30):

Most problems in PROFIBUS are caused by physical layer problems. This essentially means there are cabling issues such as terminating resistors, shielding, rounding, and EMC. Things like this can cause problems with the high speed data communication cable, which is the PROFIBUS cable. One of the important tools in this program is called “ScopeWare,” which can be accessed on the upper left corner of the screen directly to the right of the ProfiTrace tab.

There is really no good way to tell what is going on in a network without an oscilloscope. A majority of the problems previously mentioned can be seen as symptoms in ProfiTrace or messages being dropped (repeat messages, stations being lost and coming back). The user won’t be able to really find the source of the problem, if it is a physical layer issue, without an oscilloscope. When the user is on the ScopeWare tab, they will be able to see the live running scope in the scope screen. Underneath this screen there will be the familiar live list that was in the ProfiTrace tab with the scope running directly above it. A great feature is that any device in the live list can be clicked on, and it will trigger a message from that device, which will then be shown in the scope window. Every message that’s leaving the device is being triggered on and being shown on the screen. There will be a little movement or jittering within the scope window, which is due to the fact that the timing is slightly different on each cycle, but it is pretty much the same messages because of the way the PLC is programmed. They are the same bits going back and forth every time, so that’s why it looks relatively steady.

If a problem were to be introduced, such as turning off a terminating resistor, we would see what is called a reflection in the bits. This will appear in the form of small ripples at the end of the bits on the screen. It is representative of the energy that is being reflected back from the far end of the bus whenever the device sends a message. So when the device sends a message, bits are bouncing back from the other end of the bus and coming back, it shows up in the device’s bits now. Everything should still be green in the live list. The PROFIBUS is pretty good technology so it is robust and able to handle a missing terminator, but we are using a pretty small network as it is just the training kit. On a larger network or with more cable, it might be causing problems. What we look for in the scope is if the reflections go towards the zero-volt line (horizontal line in the center of the scope window). The other yellow horizontal lines represent different bits. If one of the reflections were to get close enough to zero, the device’s UARTs will test these bits they check four times per bit to see if the sample is a one or a zero. When the reflection gets close to zero, if any one of those samples is off, it will cause a bit error and there will start to be problems on the bus.

In our example, the reflection is not harmful, but we would like to figure out what it is and how to get rid of it. A cool feature is accessed when the “freeze” button is clicked, which is found above the scope window. Right above the freeze button, there are options to change the time scale, which is essentially just zooming in or out on any one of the bits. We can zoom in on a bit to further analyze it. From here we can turn on “cursors” which is located directly to the right of freeze. When this is clicked, cursors will pop up on the scope window. When looking at a zero bit, drag the bottom cursor and line it up with the straightest part of the bit where the reflection dampens out (typically on the right side). Then we want to adjust the vertical cursors so that they are lined up with any point at which the yellow line crosses the horizontal cursor we just laid down. It is difficult to be completely exact, but it’s possible to get very close. In the panel on the left side of the screen, the distance is read out in meters away from the device we are looking at. This means that the problem is 4.6 meters away (in our example) from whatever device being examined. In this case we are looking at address 15, which is the Phoenix Contact. This shows us that the problem is not at the Phoenix device but it is 4.6 meters of cable away.

When doing troubleshooting on a PROFIBUS network, the bus-fault light goes on when there is a problem. What happens in most places is people will run down to the device that has the red LED and start changing things. They’ll change the connector, the cable, the car, and so on, and no matter what they do, the red LED will stay lit. This is because the device that has the LED on is not the problem, but it is suffering from the problem. In this case, the problem is on the other end of the bus, but those reflections, by the time they get to the device on the other end, are so bad that the device is no longer able to communicate with the master. This device is basically just putting on its bus-fault light and telling us “I can’t talk anymore, there is too much noise on this bus,” but of course it’s not really telling us this. This issue can be determined using the ScopeWare. This is another fantastic part of ProfiTrace that really allows the user to nail down where any problems in the network may be. We will now turn the terminating resistor back on, unfreeze the scope, and zoom back out. It should look similar to how it was when we first opened up ScopeWare.

Bar Graph (26:55):

The next thing we will take a look at is the “Bar graph” tab, which is directly to the right of the ScopeWare one. The bar graph is measuring the amplitude of the signal coming from each device. On the graph, there is the signal and address on the far left in which the ProfiCore Ultra is connected to in order for it to be the strongest. Devices further away have a little bit less strength in signal. When we were looking at ScopeWare, we were really measuring the top of the one bit to the bottom of the zero bit. If we were to look at our address 15 in ScopeWare, we would see that the top of the one bit is at about 3V and the bottom of the zero bit is about 2.5V, so there is roughly 5.5V. When we go back to the bar graph and look at address 15 this number will be represented. This is important because it was mentioned earlier that if there are reflections they cause problems when they get close to zero. So we’ve drawn a small, red horizontal line drawn through the bar graph at 2.5V. Basically that’s 1.25V on either side of 0.

Going back to ScopeWare again, we’ve drawn a red line that represents a signal that might be 1.25V on either side of zero. Remember the reflection that was observed when the terminating resistor was turned off. If the signal level for this device were down that low, then that reflection would have caused bit-errors and all kinds of problems. The bar graph is a nice graphical way to monitor the signal level of all devices to see if there are any potential problems lurking. In our small network, everything is working well as they are well above the 2.5V line. If a bigger network is being used and things are starting to get down there, it might be wise to consider doing some things to boost voltage back up, which might be to add a repeater or shorten the cable lengths.
Topology (29:05):

The last part that is included in the troubleshooting kit Ultra Plus is the tab called “Topology,” which is located directly to the right of the bar graph tab. This can be used to calculate the topology, which is basically a drawing of the instillation. It tells the user who is connected to who in this daisy chain of PROFIBUS cables. When starting this up, it is important that the user selects where on the bus they are connected. In this case, we plugged the ProfiCore Ultra onto the PG connector on the PLC/master. So on the drop down menu, we would select master. There will also be a few warnings presented in the topology detection settings. The one that is really crucial to note is that this topology detection only works on 500 kbps and 1.5 Mbps. If the network being used is faster or slower than that then this tool will not work very well as it is a very difficult task to measure the topology. There has to be a pretty clean network in order to run this scan, but once it is complete, the results are very reliable. If there are reflections and noise on a network when a topology scan is running, it will get confused by those reflections because it is trying to measure the distance in much the way the ScopeWare did, but without a human helping. When we run the topology it will begin to calculate the distances between the devices. Again we are using a small training kit so there is not a lot of cable, maybe seven meters total. This will generate a map of the instillation. Then, a report can be generated using the report function. This allows the user to print all of this information out and save it for future reference. When there is a problem, the ScopeWare is used to determine the distance of the problem, then the diagram will help direct the user of where exactly to go.

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