IO-Link

When to Use Hygienic Design vs. Washdown

Guest Contributor: Christine Rühling, Balluff

Both washdown and hygienic design are common terms used in the food and beverage industry, and are increasingly being used in the packaging industry. These terms are used in different scenarios and easily confused with each other. What exactly are the differences between them, and in what applications are each used?

Why are hygienic design and washdown needed?

The consumer, and more specifically, the health of the consumer is the core concern of the food and beverage industry. Contaminated food can pose a danger to life and limb. A product recall damages the image of a company, costs a lot of money and as a worst case scenario can lead to the complete closing of the company. To prevent such scenarios, a producers primary objective is to make sure that the food is safe and risk-free for the consumer.image 1
In food manufacturing and packaging plants, a differentiation is made between the food area (in direct contact with the product), the spray area (product-related) and the non-food area. The requirements of the machine components are different depending on which area they are in.

The Food Area

In the food area the food is unpacked, or partially unpacked, and particularly susceptible to contamination. All components and parts that may come in contact with the food must not adversely affect this, e.g. in terms of taste and tolerability.
The following needs to be considered to avoid contamination:

  • Hygiene in production
  • Use of food contact materials
  • Food-grade equipment in Hygienic Design

These requirements result in the need for components that follow the hygienic design rules. If the component supplier fulfills these rules, the machine manufacturer can use the components and the producer can use the machines without hesitation.

Hygienic Design

Many component suppliers offer different solutions for hygienic design and each supplier interprets the design differently. So what does hygienic design mean? What must be included and which certifications are the right ones?

  • The material used must be FoodContact Material (FCM). This means that the material is non-corrosive, non-absorbent and non-contaminating, disinfectable, pasteurisable and sterilizable.
  • Seals must be present to prevent the ingress of microorganisms.
  • The risk of part loss must be minimized.
  • Smooth surfaces with a radius of < 0.8 μm are permitted.
  • There must be no defects, folds, breaks, cracks, crevices, injection-molded seams, or joints, even with material transitions.
  • There must be no holes or depressions and no corners of 90°.
  • The minimum radius should be 3 mm.

Supporting institutions and related certifications

There are different institutions which confirm and verify the fulfillment of these rules. They also support the companies during the development process.
image2
EHEDG – The European Hygienic Engineering and Design Group offers machine builders and component suppliers the possibility to evaluate and certify their products according to Hygienic Design requirements.
image33A – 3-A Sanitary Standards, Inc. (3-A SSI) is an independent, non-profit corporation in the U.S. for the purpose of improving hygiene design in the food, beverage and pharmaceutical industries. The 3-A guidelines are intended for the design, manufacture and cleaning of the daily food           accessories used in handling, manufacturing and packaging of edible products with high hygiene requirements.
image4FDA – The Food and Drug Administration is a federal agency of the United States Department of Health and Human Services, one of the United States federal executive departments. Among other things, the FDA is responsible for food safety.

What does a hygienic design product look like?

Below is an example of a hygienic design product.

 

  • Stainless steel housing VA 1.4404
  • Laser marking
  • Protection class IP69K (IEC 60529)
  • Active surface made of PEEK
  • EHEDG conform
  • FDA conform

Since the product contacting area is associated with high costs for the plant manufacturer and the operator, it’s beneficial to keep it as small as possible.

The Spray Area

In the spray area, there are different requirements than in the food area.
Depending on the type of food that is processed, a further distinction is made between dry and wet areas.

image6
Areas in the food and beverage production

Here we are talking about the washdown area. Washdown capable areas are designed for the special environmental conditions and the corresponding cleaning processes.

Washdown

Components which fulfill washdown requirements usually have the following features:

  • Cleaning agent/corrosion resistant materials (often even food compliant, but this is not a must)
  • High protection class (usually IP 67 and IP 69K)
  • Resistant to cleaning agents
image7
Photoelectric sensor for washdown requirements

Ecolab and Diversey are two well-known companies whose cleaning agents are used for appropriate tests:
Ecolab Inc. and Diversey Inc. are US based manufacturers of cleaning agents for the food and beverage industry. Both companies offer certification of equipment’s resistance to cleaning agents. These certificates are not prescribed by law and are frequently used in the segments as proof of stability.
The washdown component must also be easy and safe to clean. However, unlike the hygienic design, fixing holes, edges and threads are permitted here.

For basic information on IP69K see also this previous blog post.
To learn more about solutions for washdown and hygienic design click here.

cropped-cmafh-logo-with-tagline-caps.pngCMA/Flodyne/Hydradyne is an authorized  Balluff distributor in Illinois, Wisconsin, Iowa and Northern Indiana.

In addition to distribution, we design and fabricate complete engineered systems, including hydraulic power units, electrical control panels, pneumatic panels & aluminum framing. Our advanced components and system solutions are found in a wide variety of industrial applications such as wind energy, solar energy, process control and more.

 

The Emergence of Device-level Safety Communications in Manufacturing

Guest Contributor: Tom Knauer, Balluff

Manufacturing is rapidly changing, driven by trends such as low volume/high mix, shorter life cycles, changing labor dynamics and other global factors. One way industry is responding to these trends is by changing the way humans and machines safely work together, enabled by updated standards and new technologies including safety communications.

In the past, safety systems utilized hard-wired connections, often resulting in long cable runs, large wire bundles, difficult troubleshooting and inflexible designs. The more recent shift to safety networks addresses these issues and allows fast, secure and reliable communications between the various components in a safety control system. Another benefit of these communications systems is that they are key elements in implementing the Industrial Internet of Things (IIoT) and Industry 4.0 solutions.

Within a typical factory, there are three or more communications levels, including an Enterprise level (Ethernet), a Control level (Ethernet based industrial protocol) and a Device/sensor level (various technologies). The popularity of control and device level industrial communications for standard control systems has led to strong demand for similar safety communications solutions.

Safety architectures based on the most popular control level protocols are now common and often reside on the same physical media, thereby simplifying wiring and control schemes. The table, below, includes a list of the most common safety control level protocols with their Ethernet-based industrial “parent” protocols and the governing organizations:

Ethernet Based Safety Protocol Ethernet Based Control Protocol Governing Organization
CIP Safety Ethernet IP Open DeviceNet Vendor Association (ODVA)
PROFISafe PROFINET PROFIBUS and PROFINET International (PI)
Fail Safe over EtherCAT (FSoE) EtherCAT EtherCAT Technology Group
CC-Link IE Safety CC-Link IE CC-Link Partner Association
openSAFETY Ethernet POWERLINK Ethernet POWERLINK Standardization Group (EPSG)

 

These Ethernet-based safety protocols are high speed, can carry fairly large amounts of information and are excellent for exchanging data between higher level devices such as safety PLCs, drives, CNCs, HMIs, motion controllers, remote safety I/O and advanced safety devices. Ethernet is familiar to most customers, and these protocols are open and supported by many vendors and device suppliers – customers can create systems utilizing products from multiple suppliers. One drawback, however, is that devices compatible with one protocol are not compatible with other protocols, requiring vendors to offer multiple communication connection options for their devices. Other drawbacks include the high cost to connect, the need to use one IP address per connected device and strong influence by a single supplier over some protocols.

Device level safety protocols are fairly new and less common, and realize many of the same benefits as the Ethernet-based safety protocols while addressing some of the drawbacks. As with Ethernet protocols, a wide variety of safety devices can be connected (often from a range of suppliers), wiring and troubleshooting are simplified, and more data can be gathered than with hard wiring. The disadvantages are that they are usually slower, carry much less data and cover shorter distances than Ethernet protocols. On the other hand, device connections are physically smaller, much less expensive and do not use up IP addresses, allowing the integration into small, low cost devices including E-stops, safety switches, inductive safety sensors and simple safety light curtains.

Device level Safety Protocol Device level Standard Protocol Open or Proprietary Governing Organization
Safety Over IO-Link/IO-Link Safety* IO-Link Semi-open/Open Balluff/IO-Link Consortium
AS-Interface Safety at Work (ASISafe) AS-Interface (AS-I) Open AS-International
Flexi Loop Proprietary Sick GmbH
GuardLink Proprietary Rockwell Automation

* Safety Over IO-Link is the first implementation of safety and IO-Link. The specification for IO-Link Safety was released recently and devices are not yet available.

The awareness of, and the need for, device level safety communications will increase with the desire to more tightly integrate safety and standard sensors into control systems. This will be driven by the need to:

  • Reduce and simplify wiring
  • Add flexibility to scale up, down or change solutions
  • Improve troubleshooting
  • Mix of best-in-class components from a variety of suppliers to optimize solutions
  • Gather and distribute IIoT data upwards to higher level systems

Many users are realizing that neither an Ethernet-based safety protocol, nor a device level safety protocol can meet all their needs, especially if they are trying to implement a cost-effective, comprehensive safety solution which can also support their IIoT needs. This is where a safety communications master (or bridge) comes in – it can connect a device level safety protocol to a control level safety protocol, allowing low cost sensor connection and data gathering at the device level, and transmission of this data to the higher-level communications and control system.

An example of this architecture is Safety Over IO-Link on PROFISafe/PROFINET. Devices such as safety light curtains, E-stops and safety switches are connected to a “Safety Hub” which has implemented the Safety Over IO-Link protocol. This hub communicates via a “black channel” over a PROFINET/IO-Link Master to a PROFISafe PLC. The safety device connections are very simple and inexpensive (off the shelf cables & standard M12 connectors), and the more expensive (and more capable) Ethernet (PROFINET/PROFISafe) connections are only made where they are needed: at the masters, PLCs and other control level devices. And an added benefit is that standard and safety sensors can both connect through the PROFINET/IO-Link Master, simplifying the device level architecture.

Safety

Combining device level and control level protocols helps users optimize their safety communications solutions, balancing cost, data and speed requirements, and allows IIoT data to be gathered and distributed upwards to control and MES systems.

cropped-cmafh-logo-with-tagline-caps.pngCMA/Flodyne/Hydradyne is an authorized  Balluff distributor in Illinois, Wisconsin, Iowa and Northern Indiana.

In addition to distribution, we design and fabricate complete engineered systems, including hydraulic power units, electrical control panels, pneumatic panels & aluminum framing. Our advanced components and system solutions are found in a wide variety of industrial applications such as wind energy, solar energy, process control and more.

Non-Contact Transmission of Power & Data on Transfer Rails & Grippers

Guest contributor, Stefanie Roedl, Balluff

For press shops utilizing transfer rail systems, fixed sensor connections regularly cause frustration. Cables and contacts are often subject to heavy strain. Cables can wear out and break, damaged pins or mechanical collisions can cause hours of machine downtime, and the replacement of large multi-pin connectors comes at a high cost.

Inductive couplers offer an ideal solution: By using these non-contact, wear-free products you can eliminate pin connections and simplify job changeovers on the press. Inductive couplers transfer signals and power contact-free over an air gap. The quick-disconnect units are easy to use and require no maintenance, enabling you to meet new demands quickly. Mechanical wear is a thing of the past. This increases system availability, reduces cycle time and enhances the flexibility of workflow processes.

Inductive coupling example

Replace pin connections for transfer rails

Typically, two pin-based connectors connect the transfer rail to the transfer system on the press. The connections are on both the feed and exit sides of the rail to the control. If there is any misalignment of the connections, damage regularly occurs. By replacing the connectors with pin-free inductive couplers, the connections are simplified and repair work is minimized. Additionally you don’t have open pins exposed to the environment (dust, water, oil) that can also cause nuisances in the connection process.

Replace pin connections for grippers

To connect the transfer rail on each gripper, normally a pin-based connector is used. As the grippers are changed on each tooling change, the connectors become worn and damaged with regularity. By replacing the pin connector with non-contact inductive couplers, the two sensor signals are maintained but the maintenance of these connections is reduced dramatically. An additional “in-zone signal” verifies that the gripper is installed and connected. This provides assurance during operation.

Inductive couplers offer IO-Link functionality

Inductive coupling with IO-Link technology adds more benefits besides replacing the pin coupling. It allows users to transfer up to 32 bytes of data in addition to power for actuation or sensors. If you connect IO-Link enabled I/O hubs or valve connectors to the remote side, you can also store identification data on the IO-Link hub or valve. When the connection is established, the controller can request the identification data from the tool to ensure that the system is utilizing the correct tool for the upcoming process.

With pin based coupling you needed up to 4-5 seconds to first engage the tool and to mate the two ends of the pin couplers and then request the identification. With inductive couplers, the base only needs to be brought closer to the remote so that you quickly couple and identify the tool before engaging the tool — this takes less than a second. Additionally the base and remote do not need to be well aligned to couple. Misalignment up to 15-20 degrees of angular offset or 2-4 mm of axial offset still provides functionality.

The benefits at a glance

  • Power and signals transfer with pin-less connectivity
  • Reduced downtime due to rail or gripper repair
  • Know that the gripper is present and powered with in-zone signal
  • Inform the controller that the rail has power and connectivity to the sensors

To decide the right coupler for your next application visit www.balluff.com.

cropped-cmafh-logo-with-tagline-caps.png

CMA/Flodyne/Hydradyne is an authorized  Balluff distributor in Illinois, Wisconsin, Iowa and Northern Indiana.

In addition to distribution, we design and fabricate complete engineered systems, including hydraulic power units, electrical control panels, pneumatic panels & aluminum framing. Our advanced components and system solutions are found in a wide variety of industrial applications such as wind energy, solar energy, process control and more.

Collaborative Automation…It’s Not Just for Robots

Guest Contributor: Tom Rosenberg, Balluff

Manufacturing is made up of hundreds of discrete operations. Some are repetitive, while others are more diverse. Repetitive tasks are ideal for automation while diverse tasks require more flexibility. And while automation can be extremely flexible, that comes with a high initial investment costs and significant deployment time. The alternative? People!

Humans have the unrivaled ability to adapt to a diverse and flexible manufacturing environment. They can be productive relatively quickly with proper guidance without high initial cost investments.

But as we all know, “to err is human” and this is one of the biggest issues with manual operations. People need a little guidance from time to time. Collaboration is not just for robots; It’s for complete automation systems as well.

Collaborative automation is most important at the point-of-use, where humans are performing critical operations. Some of those common operations include:

  • Manual assembly for low volume or highly flexible operations
  • Delivery of raw materials to the point-of-use
  • Kit assembly for down-stream operation
  • Machine setup and change-over
  • Machine maintenance and calibration

All of these functions can be done error-free and with little training by simply guiding people within their current work envelope, also referred to as their point-of-use. This type of a lean function provides hands-free guidance in the form of indication devices connected directly to your automation system allowing workers to stay focused on the task at hand instead of looking elsewhere for instructions.

With the technology of IO-Link, smart indication devices can now show much more information to all the people involved in specific manufacturing tasks. Automation has an immediate and direct connection to the people that are so vital.

For example, in a manually-fed weld-cell, the smart indicators are capable of not only signaling that the part is loaded correctly, but also whether the part is out of alignment (shown here by the red indicator) or that something wrong with one of the automation components such as a stuck pneumatic clamp.

Figure 1A manually-fed weld-cell with smart indicators is capable of not only signaling that the part is loaded correctly, but also if the part is out of alignment (shown by the red indicator) or that there is something wrong with one of the automation components such as a stuck pneumatic clamp.

Even better, with IIoT technology, trends can be analyzed to determine if the fixture/tool could be optimized for production or to identify common failure points. This all leads to tighter collaboration with operations, maintenance personnel and production supervisors.

A traditional kitting station, sometimes referred to as a supermarket, is another ideal application for smart indicators. Not only can they guide a single operator to the intended part to pull, they can guide multiple operators at the same time.  Also, smart indicators can inform of incorrect pulls, potential bin options (a physically closure bin), directional information, and inventory levels. And again, with IIoT technology, trends can be analyzed to determine proper layout, individual personnel performance and system throughput. The automation system collaborates with operations, forklift drivers and production supervisors.

Regal_v06_01_V3A traditional kitting station, sometimes referred to as a supermarket, with smart indicators to guide operators to the intended part to pull.

So, take a look and see what a collaborative automation system utilizing smart indicators can do for your manual operations. You might be surprised.

Safely Switch Off Cylinders While Transmitting Field Data

Guest contributor: Matthias Wolfer, Balluff

 

Is it possible to safely switch off cylinders while simultaneously transmitting field data and set up the system in accordance with standards? Yes!

In order to rule out a safety-critical fault between adjacent printed circuit board tracks/contact points (short circuit) according to DIN EN ISO 13849, clearance and creepage distances must be considered. One way to eliminate faults is to provide galvanic isolation by not interconnecting safety-relevant circuits/segments. This means  charge carriers from one segment cannot switch over to the other, and the separation makes it possible to connect the safety world with automation — with IO-Link. Safely switching off actuators and simultaneously collecting sensor signals reliably via IO-Link is possible with just one module. To further benefit from IO-Link and ensure safety at the same time, Balluff’s I/O module is galvanically isolated with a sensor and an actuator segment. The two circuits of the segments are not interconnected, and the actuator segment can be safely switched off without affecting the sensors. Important sensor data can still be monitoring and communicated.

The topological structure and the application of this safety function is shown in this figure as an example:

2D-SAGT-Betriebsanleitung_v2

  1. A PLC is connected to an IO-Link master module via a fieldbus system.
  2. The IO-Link master is the interface to all I/O modules (IO-Link sensor/actuator hubs) or other devices, such as IO-Link sensors. The IO-Link communication takes place via a standardized M12 connector.|
  3. Binary switching elements can be connected to the galvanically isolated sensor/actuator hub (BNI IOL-355). The four connection ports on the left correspond to the sensor segment and the four ports on the right correspond to the actuator segment. Communication of the states is done via IO-Link.
  4. The power supply for both segments takes place via a 7/8″ connection, whereby attention must be paid to potential separated routing of the sensor and actuator circuits. Both the power supply unit itself and the wiring to the IO-Link device with the two segments must also ensure external galvanic isolation. This is made possible by separating the lines with a splitter.
  5. An external safety device is required to safely interrupt the supply voltage of the actuator segment (four ports simultaneously). Thus, the module can implement safety functions up to SIL2 according to EN62061/PLd and ISO 13849.

For example, this can happen through the use of a safety relay, whereby the power supply is safely disconnected after actuation of peripheral safety devices (such as emergency stops and door switches). At the same time, the sensor segment remains active and can provide important information from the field devices.

The module can handle up to eight digital inputs and outputs. If the IO-Link connection is interrupted, the outputs assume predefined states that are retained until the IO-Link connection is restored. Once the connection is restored, this unique state of the machine can be used to continue production directly without a reference run.

An application example for the interaction of sensors and actuators in a safety environment is the pneumatic clamping device of a workpiece holder. The position feedback of the cylinders is collected by the sensor segment, while at the same time the actuator segment can be switched off safely via its separately switchable safety circuit. If the sensor side is not required for application-related reasons, galvanically isolated IO-Link modules are also available with only actuator segments (BNI IOL 252/256). An isolated shutdown can protect up to two safety areas separately.

cropped-cmafh-logo-with-tagline-caps.pngCMA/Flodyne/Hydradyne is an authorized  Balluff distributor in Illinois, Wisconsin, Iowa and Northern Indiana.

In addition to distribution, we design and fabricate complete engineered systems, including hydraulic power units, electrical control panels, pneumatic panels & aluminum framing. Our advanced components and system solutions are found in a wide variety of industrial applications such as wind energy, solar energy, process control and more.

What Exactly is Safety Over IO-Link?

Automation Pyramid.png

This integrated safety concept is the logical continuation of the IO-Link philosophy. It is the only globally available technology to build on the proven IO-Link standards and profisafe. This means it uses the essential IO-Link benefits such as simple data transport and information exchange, high flexibility and universal applicability for safety signals as well. Safety over IO-Link combines automation and safety and represents efficient safety concepts in one system. Best of all, the functionality of the overall system remains unchanged. Safety is provided nearly as an add-on.

In the center of this safety concept is the new safety hub, which is connected to an available port on an IO-Link master. The safety components are connected to it using M12 standard cable. The safety profisafe signals are then tunneled to the controller through an IO-Link master. This has the advantage of allowing existing infrastructure to still be used without any changes. Parameters are configured centrally through the user interface of the controller.

Safety Hub

The safety hub has four 2-channel safe inputs for collecting safety signals, two safe outputs for turning off safety actuators, and two multi-channel ports for connecting things like safety interlocks which require both input and output signals to be processed simultaneously. The system is TÜV- and PNO-certified and can be used up to PLe/SIL 3. Safety components from all manufacturers can be connected to the safe I/O module.

Like IO-Link in general, Safety over IO-Link is characterized by simple system construction, time-and cost-saving wiring using M12 connectors, reduction in control cabinet volume and leaner system concepts. Virtually any network topology can be simply scaled with Safety over IO-Link, whereby the relative share of automation and safety can be varied as desired. Safety over IO-Link also means unlimited flexibility. Thanks to varying port configuration and simple configuration systems, it can be changed even at the last minute. All of this helps reduce costs. Additional savings come from the simple duplication of (PLC-) projects, prewiring of machine segments and short downtimes made possible by ease of component replacement.

Development of IO-Link, number of sold nodes.png

To learn more about Safety over IO-Link, visit www.balluff.com

cropped-cmafh-logo-with-tagline-caps.pngCMA/Flodyne/Hydradyne is an authorized  Balluff distributor in Illinois, Wisconsin, Iowa and Northern Indiana.

In addition to distribution, we design and fabricate complete engineered systems, including hydraulic power units, electrical control panels, pneumatic panels & aluminum framing. Our advanced components and system solutions are found in a wide variety of industrial applications such as wind energy, solar energy, process control and more.

Hydraulics with IO-Link: Reduced effort, high value

Guest contributor: Theobald Herrmann, Bosch Rexroth

In almost all industries, machine users require increased flexibility for production means for small batches and continuous diagnostics of all actuators and sensors to increase availability. In addition to this, there is quickly increasing horizontal and vertical connection of machinery and systems for Industry 4.0 applications. The open standard IEC 61131-9, IO-Link, fulfills these requirements at low connection costs and energy consumption. Flexibility of hydraulics is increased by transmission of parameter changes in running operation. Provision of diagnostics information offers numerous opportunities to extend the concepts of predictive maintenance to increase availability of the systems. The manufacturer-independent IO-Link can be integrated easily and quickly in any industrial automation application.

Standardized wiring and electronic name plate support commissioning and increase availability

• Open standard for bi-directional point-to-point connections in parallel to field bus
• Easy connection with standard cables and M12 connectors
• No additional engineering tool necessary, possible configuration via control system.
• Data for predictive maintenance and quick device replacement
 Industry 4.0-compatible hydraulic components for vertical flow of information

Introduction: Limits of serial field bus communication

The introduction of field bus technology in the 1980s was the starting point for horizontal connection of decentralized actuators within machinery. Serial wiring lead to a considerable reduction in cabling and opened new possibilities for modularization in mechanical engineering. Field buses as well as most current real-time Ethernet protocols are manufacturer-specific, proprietary systems. The protocols have been developed by control system manufacturers and focus on communication between own electric control systems and selected peripherals. For actuators, sensors and other third-party equipment, either their manufacturers or system integrators are required to provide suitable interfaces in hardware and software for the respective field bus. This is very complex as device profiles and software have to be created in the respective PLC for every individual field bus and control system of each manufacturer.

Possibilities for hydraulic connection

Integration of hydraulics in modern automation systems can be realized in different ways. Numerous existing machine concepts apply on-board electronics for control of hydraulic valves. Exchange of digital information is restricted and only possible if the respective device is connected to a superior control system via individual wiring. This state-of-the-art in technology increasingly no longer meets the requirements of end users.

The alternative are valves with integrated field bus connection. These, however, require extensive wiring as well as integration into the control system and the respective field bus protocol by means of dedicated software. Both requires considerable effort that is too high particularly for price-sensitive applications.

Thanks to IO-Link, machine manufacturer and system integrators are enabled to integrate for example proportional hydraulic series valves and sensors into digital communication structures with very little engineering effort. With its simple communication structure, IO-Link has low hardware requirements. Additionally, the standardized M12 connection technology enables simple and cost-efficient connection of hydraulic valves in the field. This way, previously “deaf-mute” components with analog control are transformed in communicating and flexible actuators and sensors.

IO-Link: Manufacturer-independent and compatible with all field bus protocols

The manufacturer-independent IO-Link according to IEC 61131-9 standardizes connection technology for actuators, sensors and other equipment and provides a digital communication protocol for data exchange between control systems and devices regardless of the field bus. Field bus technology is not replaced but extended. Parallel communication enables machine manufacturers use of IO-Link with all protocols and integration of IO-Link-compatible devices into various concepts without additional effort.

IO-Link is currently already supported by around 130 device manufacturers and companies in the field of technology. Around 40 manufacturers offer IO-Link Masters and the standard is supported by nine manufacturers of control systems with central Masters and respective engineering tools. IO-Link devices are in the product range of almost sixty manufacturers of sensors, actuators and other peripherals. Rexroth, for example, now also offers hydraulic proportional valves and pressure sensors with respective technology. Function and performance of these proportional valves are identical to series valves. However, they also offer all options for bi-directional communication via IO-Link. This way, the hydraulics can be integrated seamlessly into connected structures. Parameters can be changed and operating states changed by the control system during running operation.

IO-Link system set-up

A full IO-Link system consists of one centralized or decentralized IO-Link Master, one or more IO-Link devices as well as unshielded 3 or 5-conductor standard cables with M12 connectors. Project planning and parameterization of the IO-Link Master can be realized in the control system hardware or an optional engineering tool. The point-to-point connections between IO devices and the automation system are established by the Master. It serves as the interface to the superior control system.

bild01_offenestandards_en

IO-Link Masters are offered by around 50 manufacturers for connection of one IO device per port. The selection includes options for the IP20 control cabinet as well as decentralized modules with protection class IP65/67 for installation at machinery. Particularly in large-scale systems, cabling is considerably reduced.

For decentralized IO-Link Masters, the user organization of IO-Link has defined M12 plug-in connectors with three or five conductors. The 5-pole version “Class B” port is used for devices with increased current consumption like hydraulic valves. The 3-pole version “Class A” port provides an energy supply of up to 200 mA which is sufficient for most sensors. In contrast to analog controls, unshielded cables are sufficient for fault-free communication over a cable length of up to 20 meters. IO-Link standardizes connection technology for all actuators and sensors and eliminates numerous sources of errors during the installation of systems. Otherwise complicated and expensive cable dimensioning with individual wiring and shielding is no longer required. In addition, the logistic effort is reduced thanks to application of uniform M12 cables for sensors and actuators.

Rapid commissioning per software

Every IO-Link device features an electronic device description, referred to as IO Device Description (IODD). It provides standardized important information:

• Device data
• Text description
• Identification, process and diagnosis data
• Communication properties
• Device parameters with value range and default value.
• Image of the device
• Logo of the manufacturer

The IODD set-up is identical for all devices of all manufacturers. The IODD enables automatic recognition of the device by the IO-Link Master for immediate parameterization. Also automatically, device descriptions are included in the system documentation.

For project integration of the IO-Link Master in overall automation, commissioning personnel use the engineering tools of the respective PLC manufacturer. The IO-Link Master is selected from the device portfolio and added to overall automation. Depending on the control system manufacturer, all blocks for communication are available in a library for free.

bild02_io_link_en

Via IO-Link to Industry 4.0

IO-Link enables access to device data either directly from the control system or remotely via networks from any location. Particularly important for future-oriented concepts: Already today, IO-Link offers type and instance data of Industry 4.0 devices according to the definition of the German “Plattform Industrie 4.0” initiative.

This way, also hydraulic actuators meet all conditions for future requirements of Industry 4.0 applications. Additionally, this approach is well-suited for subsequent connection of existing machinery and systems with low effort. Users replace installed proportional valves and sensors by interchangeable options with IO-Link connection for direct communication with actuators and sensors.

Diagnosis functions for increased availability

The diagnosis functions of IO-Link devices enable new maintenance concepts and considerably reduce repair times. Now possible call-up of device information in parallel to the process forms the basis for condition-oriented and predictive maintenance concepts. In this respect, proportional valves report whether they are functional as well as errors like under or overvoltage. In addition, the valve and sensor status is displayed for transparent error analysis. An integrated operating hour indicator enables calculation of the residual life-cycle for maintenance and decision-making on further use of the valve.

In case of faults, IO-Link accelerates diagnosis thanks to remote access for maintenance specialists to identify the type and location of any errors. Precise localization without personal presence at the system alone considerably reduces reaction times. If necessary, the maintenance technician opens the IODD file of the respective device in the control system. Other than before, components do not need to be disassembled to decipher hardly readable labels and manufacturers and types no longer need to be looked for in system documentations. Thanks to the electronic name plate, all this information can now be accessed with just one mouse click to initiate the respective order without delay.

IO-Link follows the plug & play principle. Replaced devices are recognized by the IO-Link Master according to their IODD file and the respective parameters are automatically transferred without any actions in the software. This way, even less experienced technicians are enabled to replace components without problems to considerably reduce system downtimes.

Summary

The open IO-Link standard establishes continuous communication with sensors and actuators irrespective of the used field bus. Now, even hydraulic proportional valves can be intelligently, easily and cost-effectively integrated in bi-directional digital communication. This simplifies commissioning in hardware and software and enables flexible adjustment of hydraulic valves for varying production processes. Increased requirements for flexible machinery and systems are now complied with. Extended diagnosis information enables condition-oriented and predictive maintenance concepts and standstill and maintenance times are reduced. This increases the availability of machinery. In addition, IO-Link enables future-proof integration of hydraulic valves into connected structures as Industry 4.0 components with all their related features.

Why hydraulics and IO-Link? Click here

Learn more about Rexroth and IO-Link

cropped-cmafh-logo-with-tagline-caps.pngCMA/Flodyne/Hydradyne is an authorized Bosch Rexroth distributor in Illinois, Wisconsin, Iowa and Northern Indiana.

In addition to distribution, we design and fabricate complete engineered systems, including hydraulic power units, electrical control panels, pneumatic panels & aluminum framing. Our advanced components and system solutions are found in a wide variety of industrial applications such as wind energy, solar energy, process control and more.