DigiKey-eMag-Exploring the Control Cabinet-Vol 21

We get technical

Exploring the Control Cabinet | Volume 21

Cabinet safety – A paramount

consideration in any industrial application The benefits of upgrading to stainless steel Saving time with tool-free wiring Surge protection in industrial control cabinets

we get technical

Cabinet safety – A paramount consideration in any industrial application Sponsored by Panduit The benefits of upgrading to stainless steel Sponsored by Hammond Saving time with tool-free wiring Sponsored by Phoenix Surge protection in industrial control cabinets Using a unified cybersecure platform to support comprehensive industry 4.0 connectivity How smart motor controls can maximize resilience and uptime Using temperature controllers and micro PLCs to speed small-scale automation projects How the simple DIN rail solves for modularity, flexibility, & convenience in industrial systems

4 8

12 16

20 28 34 42 48

How to quickly design and deploy IIoT-ready machines

Editor’s note Welcome to the DigiKey eMagazine Volume 21 – Exploring the Control Cabinet. In any industrial automation application, whether on the manufacturing floor or in an industrial kitchen, there is a control cabinet. This cabinet is vital to the operation of any automated process. Blending machine and process, the cabinet drives efficiency and precision. Opening the door to an industrial control cabinet is like stepping into the nerve center of modern industry. Inside, you'll find a meticulously organized array of devices, each playing a crucial role in the system's functionality. From the programmable logic controllers (PLCs) that act as the brain of the operation to the human-machine interfaces (HMIs) that provide real-time insights, every element is designed to work in harmony. Exploring the industrial control cabinet reveals the sophisticated balance between technology and engineering, showcasing the advancements that drive innovation in industrial settings. These advancements allow us to drive smarter machines, reduce waste, increase efficiency and productivity while maintaining a high level of accuracy and quality. In this magazine, we will dive into topics such as speed drives and frequency drives, DIN rail power, cybersecurity, de-energizing circuits, terminal blocks and industrial interconnect, thermal regulation, and more. We hope you find this collection of articles helpful and can spark new ideas to innovate more in the world of industrial automation.

Article Name

Cabinet safety – A paramount

consideration in any industrial application

In industrial environments, electrical cabinets remain one of the most dangerous points of contact for workers. Even when the power is shut off, residual voltage or partial disconnect switch failures can leave components energized. Each year, hundreds of arc flash events and electrical injuries occur because someone assumed the cabinet was safe to open. Workers must verify the absence of voltage before accessing electrical enclosures. However, traditional methods using handheld test instruments are complex and time-consuming. Even permanent tools like voltage indicators and test portals can fall short when it comes to confirming true de-energization. That’s where absence of voltage testers (AVTs) come in. These systems automate the verification process, giving workers a clear indication—without opening the enclosure—whether it is truly de-energized. This article explores the risks associated with conventional verification methods, and how Panduit’s VeriSafe AVT addresses their shortcomings. The problem with traditional methods Industrial workers rely on a variety of tools to assess electrical safety, but not all are designed— or approved—for verifying the

absence of voltage. Among the most commonly used are voltage indicators and test portals. While both offer some insight into the electrical status of equipment, they each carry limitations that can compromise safety when used for absence of voltage verification. Voltage indicators are simple, permanently mounted devices that illuminate when voltage is present, typically between 40V and 1000V. While they offer a quick visual warning, they are fundamentally limited when it comes to confirming de-energization. A non-illuminated indicator doesn’t necessarily mean the system is safe; LED or fuse failures, poor installation, or open circuits can all produce a false negative. Additionally, since these devices route line voltage directly to the enclosure door, they introduce a potential shock hazard when a worker is troubleshooting with the door open. OSHA has stated that voltage indicators should not be used to verify de-energization. Test portals offer another option. These devices allow technicians to connect a handheld tester to measure voltage without opening the cabinet. While helpful for troubleshooting, test portals are not well-suited to confirming a safe- to-open condition. They cannot verify that the internal leads are properly connected at the time of testing and are vulnerable to fusing issues. Either condition could show a zero-voltage reading when

voltage is actually present. Like indicators, test portals can also route hazardous voltage to the door, exposing workers to additional risk. Neither voltage indicators, nor test portals satisfy NFPA 70E’s requirements for absence of voltage verification. According to Article 120.5(7), proper verification must include testing each phase both phase-to-phase and phase-to- ground, using an adequately rated instrument. Exception 1 allows for permanently mounted test devices, but only if they meet strict criteria. Devices must be UL 1436 listed, test all phases, and perform self- verification using a known voltage source before and after testing. Both voltage indicators and test portals do not fulfil these conditions. While OSHA does not define detailed performance requirements

for voltage testing tools, it recognizes NFPA 70E as the

benchmark for electrical safety. By that standard, absence of voltage testers are the only permanently mounted device currently aligned with both best practices and regulatory expectations.

Introducing absence of voltage testers

Absence of Voltage Testers offer a streamlined, automated approach to verifying that electrical equipment is de-energized before access. Unlike voltage indicators

we get technical

Cabinet safety – A paramount consideration in any industrial application

or test portals, which either show the presence of voltage or allow indirect measurement, AVTs are dedicated safety devices built to verify that no voltage is present inside an enclosure. The core advantage of AVTs is that they automate a process that would otherwise require multiple steps and tools. At the push of a button, the system initiates an internal sequence: it checks that the tester itself is functioning, verifies that sensor leads are properly connected, tests each phase both phase-to-phase and

phase-to-ground, and uses a known voltage source before and after each test to verify the tester is functioning correctly. If all criteria are satisfied, a visual indication is provided to confirm that the absence of voltage has been verified. This automation reduces the chance of human error and eliminates the need to open the cabinet for initial testing. Industrial electrical manufacturer Panduit offers their VeriSafe Absence of Voltage Tester as one such solution. Once installed, it allows a qualified worker to initiate

the test sequence from outside the enclosure. By automating each verification step and providing a clear green-light indication when the system is de-energized, VeriSafe helps support safety without requiring handheld testers or direct exposure to conductors. The hardware behind Panduit’s VeriSafe AVT The VeriSafe AVT is designed around a modular architecture that separates operator interaction from high-voltage components,

Comparison of testing methods. (Image source: Panduit.)

helping reduce risk during electrical maintenance. The system is engineered for testing three- phase circuits up to 600V. At the center of the system is the indicator module, which mounts externally in a standard 30mm knockout and provides clear visual cues with red, yellow, and green LEDs to guide workers through each phase of testing. This interface removes the need to open the cabinet during initial verification, keeping personnel safely distanced from energized conductors. Inside the enclosure, the isolation module acts as a safeguard. It ensures that hazardous voltage remains contained, and includes output contacts for integration with alarms or other safety systems. Connecting the modules is a replaceable cable assembly with right-angle connectors, which save space. The sensor leads— two per phase—can be installed on either side of the disconnect and are kept physically separated to ensure accurate connection to the circuit under test. Each AVT system is tested to NEMA 4X, IP66, and IP67 standards, offering protection against dust, water, and corrosion. Versions rated for Class I, Division 2 and Zone 2 hazardous locations are available, making VeriSafe suitable for demanding industrial applications.

The system includes a long-life industrial battery that can be accessed from the front panel and is easily replaceable without tools. Additional features include built- in overcurrent protection, which eliminates the need for external fusing and prevents failure modes common in older testing approaches. Real-world case study: grounding failure A case study involving a 480V three-phase system highlights the difference that a fail-safe device can make. In this scenario, a disconnect switch had partially failed, leaving one phase live while the other two were open. Compounding the danger, the ground leads had not been properly terminated. To a worker preparing to access the panel, the system appeared de-energized. Standard test portals and voltage indicators gave false readings, showing no voltage across any phase. Had a worker relied solely on these tools, they would have opened the enclosure while one conductor remained energized, risking shock, arc flash, or equipment damage. Panduit’s VeriSafe AVT detected that the sensor leads were not properly grounded and halted the test sequence, indicating that the

installation could not be verified. This fail-safe response prevented a potentially dangerous incident, underscoring the value of automated absence of voltage verification. Conclusion Electrical cabinet safety begins well before a door is opened. Even with power shut off, residual voltage or equipment failures can leave components energized, posing serious risks to workers who assume the system is safe. Traditional tools like voltage indicators and test portals are not equipped to verify the absence of voltage. These methods can produce false negatives, fail to detect installation errors, and do not meet the standards outlined in NFPA 70E or UL 1436. Panduit’s VeriSafe AVT addresses this gap by automating the verification process and ensuring the test itself can be trusted. By detecting faults, performing self- checks, and isolating hazardous voltage, the system eliminates many of the failure modes associated with other testing methods—and helps set a higher standard for electrical safety.

To learn more, visit VeriSafe ATV.

we get technical

The benefits of upgrading to stainless steel

The electrical and control cabinets in industrial

steel maintains its structural integrity. The material protects control cabinets through its resistance to UV exposure and temperature fluctuations, ensuring long-term performance. Stainless steel grades and composition There are more than 150 grades of stainless steel, each with varying combinations of alloy elements. According to ASTM A941, stainless steel must have a minimum chromium content of 10.5% and a maximum carbon content of 1.20%. Additional elements, such as nickel and molybdenum, influence properties like corrosion resistance and tensile strength. Two of the most widely used stainless steel grades in industrial applications are 304 and 316: ■ 304 stainless steel (18% chromium and 8% nickel) is the most common. It offers standard corrosion resistance, strength, and ease of maintenance, making it suitable for general industrial use. ■ 316 stainless steel (16% chromium, 10% nickel, and molybdenum) is the second most popular in sales volume. It provides superior corrosion resistance to chlorides, acids, and alkalis. It is suitable for environments like food processing, medical

Material advantage of stainless steel

environments are constantly subjected to physical stress, humidity, water exposure, particulate matter, and corrosive chemicals. Despite protective coatings, the traditional enclosures degrade over time, compromising their ability to protect the internal electrical systems. This degradation has a significant impact—it reduces system reliability, increases the risk of electrical faults that may be hazardous to floor operators, and drives up the maintenance and replacement costs. In industries where exposure to harsh chemicals is unavoidable, it is crucial to select a more durable alternative. One such alternative is stainless steel. With its high resistance to corrosion, better mechanical strength, and reduced maintenance needs, stainless steel has become the material of choice for industrial enclosures. It delivers a robust solution needed for control cabinets in challenging conditions, where conventional options often fail to meet performance standards. This article explores the strategic reasons for upgrading to stainless steel enclosures, showcasing examples from Hammond Manufacturing.

Understanding the material advantages of stainless steel is crucial for selecting the right grade for a specific application. In comparison to carbon steel, stainless steel has additional alloying elements—chromium, molybdenum, and nickel—that improve its corrosion resistance. When exposed to oxidizing agents, such as saltwater or chemicals, chromium forms a protective layer of chromium oxide that shields the surface from further corrosion. One of the most practical advantages of stainless steel is its low maintenance. Traditional enclosures require periodic inspections, repainting, and replacement due to rusting. By contrast, stainless steel enclosures resist rust and chemical damage over extended periods, reducing operational downtime. The clean aesthetics of stainless steel make it an ideal choice for the food and beverage, pharmaceutical, and water treatment industries. Its smooth and non-porous structure allows for easy cleaning even in environments where frequent hosing or chemical washdowns are required. In outdoor or extreme temperature applications, such as rooftop HVAC units and remote utility stations, stainless

we get technical

The benefits of upgrading to stainless steel

equipment, coastal facilities, and locations with high salt concentrations and aggressive cleaning agents.

The latter is suitable for the harsh environments of the food and chemical industries. All the external hardware—hinges, latches, and pins—is made from stainless steel to prevent rust. Unlike spot-welded cabinets that allow water ingress through seam cracks, the EN4SDSS enclosures feature fully welded seams for enhanced structural integrity, protecting against water and dust. These enclosures offer design flexibility, with removable and interchangeable doors for ease of modification and reconfiguration. Also, the door alignment guide on 36” wide models prevent misalignment and assists in proper closure of the enclosures. In terms of protection ratings and standards, the EN4SDSS series complies with NEMA Type 3R, 4, 4X, 12, and 13, which indicate protection against wind, dust, rain, sleet, ice formation, and corrosion. The enclosure is also compliant with UL 508A Type 3R, 4, 4X, and 12, as well as CSA Type 3R, 4, 4X, and 12. These enclosures are available in a wide range of sizes, with widths from 12 inches (305 mm) to 72 inches (1829 mm), heights from 12 inches (305 mm) to 36 inches (914 mm), and depths from 6 inches (152 mm) to 12 inches (305 mm).

Additionally, Hammond Manufacturing offers the EJSS (Eclipse Junior Stainless Steel) series (Figure 2) as a stainless steel enclosure solution for wall- mount applications. They are designed for use in junction boxes and electrical wiring applications within compact installations.

Figure 1: Stainless steel enclosures from Hammond’s EN4SDSS series. Feature fully welded seams for structural integrity. (Image source: Hammond Manufacturing)

Figure 2: Stainless steel enclosures from Hammond’s EJSS series. Made of natural stainless steel with a smooth brushed finish. (Image source: Hammond Manufacturing) These enclosures house components in high-moisture environments or corrosive conditions. Similar to the previously discussed Eclipse enclosures, the EJSS series also complies with the NEMA standards. In enclosures exceeding 4” x 4” dimensions, a galvanized steel inner panel is incorporated as standard. The panel provides a

Stainless steel enclosures The Hammond Manufacturing EN4SDSS series (Figure 1) is an example of a stainless steel wall-mount enclosure. It demonstrates advantages for rugged industrial environments. Available in 14-gauge for larger sizes and 16-gauge for smaller sizes, this series comes in 304 and 316L stainless steel grades.

must deliver long-term protection and reliability against extreme industrial conditions of humidity, temperature, dust, water, and other corrosive elements. Solutions offered by Hammond Manufacturing through the EN4SDSS and EJSS series address this need with better corrosion resistance and rugged construction. Making this strategic decision to upgrade to a stainless steel enclosure will reduce operational risks and extend the enclosure's life. This will lower the total cost of ownership even if the initial investment is higher.

For industries that demand performance, hygiene, and

practical mounting surface for internal electrical components, including DIN rails and terminal blocks. The design features a welded mounting bracket integrated into the back of the enclosure, providing ease of installation on walls and panels. Conclusion As industrial operations become increasingly complex, there is a growing need for robust equipment enclosures to support the electrical and electronic control systems. The enclosures

durability, stainless steel is more than an option, but a necessity.

we get technical

Saving time with tool-free wiring

Shown in the closed position, a Push-X terminal block features a contact spring that engages when a conductor presses against its release surface. (Image courtesy: Phoenix Contact.)

After years in the field, few things test an electrician’s patience like a stubborn terminal block. You’re crammed into a control cabinet, fumbling with a screwdriver while trying not to overtighten a screw that may already be on its last thread. Strip the wire just a bit too long and you’re dealing with exposed copper. Do it too short and you risk a poor contact.

These frustrations aren’t new. Traditional screw-type terminal blocks have long been the industry standard, but their limitations are well known. Mechanical stress and vibration can cause wires to loosen over time, even if the connection felt solid when installed. Screws introduce another layer of risk: overtightening can damage conductors, while under-

tightening leaves room for dangerous arcing or overheating. Inconsistent insulation stripping only compounds the problem. With loose connections generating heat, insulation can degrade over time, increasing the likelihood of fire hazards. Installation itself can be a chore. Every wire demands a tool, and reaching terminal screws within confined spaces can seriously challenge an electrician’s

dexterity. For high-density applications, the difficulty isn’t just in connecting wires—it’s about managing space and routing in an environment that may already feel like a game of electrical Tetris. Electrical components manufacturer Phoenix Contact’s Push-X terminal blocks offer a smart alternative to the headaches of screw-type terminals. Designed for tool-free installation, Push-X enables direct wiring of all conductor types—including stranded styles—without the need for ferrules. That means installers can leave the screwdriver behind and rely on a single tool: a wire stripper. Once stripped, the conductor is simply inserted into the terminal. This approach not only speeds up installation but also reduces the variability introduced by torque tools, while offering a more reliable connection in tight or complex spaces. A closer look at the Push-X design At the core of Push-X technology is a pre-tensioned contact spring that activates as soon as a conductor is inserted. With a simple, tool-free motion, the wire taps the release surface inside the clamping chamber, triggering the spring to snap closed and lock the wire into place. This mechanism works regardless of wire type—whether it’s rigid, stranded, or flexible, with or without ferrule.

In many ways, Push-X solves the most common frustrations associated with screw-type terminal blocks. For starters, the contact spring applies a consistent, factory-calibrated force to each wire, completely removing the guesswork involved in tightening screws. This ensures repeatable, high- quality connections regardless of the installer’s hand strength or angle of approach—important in panels where space constraints make ideal positioning nearly impossible. There’s no risk of crushing a conductor with too much torque or leaving it vulnerable to vibration by keeping it too loose. Once engaged, the spring holds the conductor securely over time, even in high- vibration environments. Push-X is designed to accommodate small wires—down to 0.5 mm² (20 AWG) for rigid and 1.5 mm² (14 AWG) for flexible conductors—demonstrating the minimal force required to trigger the contact spring. Even fine-stranded wires trigger the mechanism easily, a major step forward from earlier push-in designs that required ferrules or extra force. Conductor release is just as simple. An orange pusher marked with an “X” pops up when a wire is inserted, signaling that the connection has been made. Pressing it down again both releases the wire and resets the spring, so the block is immediately ready for the next conductor.

Push-X also gives installers more flexibility in how they route and terminate wires within dense control cabinets. Because the terminal block opens automatically at the factory, users don’t need to preload the mechanism or pry it open themselves—wiring is a one-step process. The lateral entry design reduces the bending radius of conductors, which helps preserve wire markings and makes it easier to manage cable routing. These terminal blocks serve to close the gap in the PTV and PTPOWER lateral spring- cage terminals range. The XTV series is the first to incorporate Push-X technology, and its thoughtful features extend beyond the clamping mechanism itself. Available in 6, 10, and 16 mm² versions, the series supports conductor sizes up to 25 mm² (4 AWG) and includes feed- through blocks as well as 3- and 4-conductor variants. These multi-conductor models reduce the number of terminal blocks required on a DIN rail, freeing up panel space and simplifying wiring layouts. Color-coding and labeling further facilitate installation. Alongside the standard gray versions, the XTV series includes green-yellow protective conductor blocks to align with the color of protective earth cables. Each block is also labeled with a QR code, giving installers instant access to documentation, datasheets, and installation guides in multiple languages.

we get technical

Saving time with tool-free wiring

Push-X terminal blocks have also been tested extensively by Phoenix Contact. Despite the low insertion force required to engage the spring, the design resists accidental triggering. Drop tests and simulated shipping conditions confirm that the mechanism won’t prematurely activate from vibration or impact. The XTV series handles up to 76 A at 1000 V (IEC) and 75 A at 1000 V (UL). It is also compatible with Phoenix Contact’s broader CLIPLINE complete terminal block system, allowing integrators to use common accessories such as bridges and switching jumpers across multiple product lines. Applications of Push-X Technology Push-X terminal blocks are designed for a range of control and distribution tasks across industries. In factory and building automation, they help simplify dense wiring inside control panels and distribution boxes. The tool-free connection method is useful in settings where space is limited and installation times are tight, such as during equipment upgrades or panel retrofits. Process industries like water treatment and food production often involve environments with vibration or regular maintenance

In its factory setting, the pusher is depressed. The orange pusher pops up when the contact spring engages a conductor. (Image courtesy: Phoenix Contact.)

Push-X terminal blocks come in three sizes and are available in 2, 3, and 4-conductor variants. (Image courtesy: Phoenix Contact.)

schedules. Here, a secure, low-maintenance terminal

these advantages translate into meaningful time savings, fewer wiring mistakes and a lower risk of accidental electrocution. By rethinking a task that’s long been more tedious than it should be, Push-X makes wiring in the panel a little less frustrating, and a lot more efficient.

Conclusion For electricians used to wrestling with terminal screws within cramped enclosures, Push-X offers a welcome shift. Just strip the wire and push it in; no torque tools or second- guessing required. Push-X’s preloaded spring grips a wide range of wire types and sizes, whether you’re using ferrules or not. And when it’s time to make a change, a tap of the pusher releases the conductor and resets the terminal for the next job. When wiring dozens— or hundreds—of conductors,

connection can reduce the need for rework. Push-X also has a role in energy infrastructure— particularly in renewable systems and transportation—where field wiring conditions vary and consistent connections must hold up over time. From signal wiring in marshaling panels to power distribution in data centers and conductor management in automotive systems, Push-X supports faster wiring while keeping the process straightforward.

To learn more, visit Push-X Terminal Blocks.

we get technical

Article Name

Surge protection in industrial control cabinets By Abhishek Jadhav for DigiKey

Control cabinets serve as the powerhouse of any industrial facility, housing programmable logic controllers (PLCs), communication devices, sensors, variable frequency drives, and human-machine interface panels. As these components become more compact and complex, their susceptibility to damage from transient overvoltage increases. These transient overvoltages are short-duration (typically milliseconds), high-magnitude voltage peaks with fast-rising edges, capable of reaching up

to 6,000 volts even on a low- voltage consumer network. When a voltage surge exceeds the specific dielectric strength of the devices, it can affect the entire electrical system. It leads to short circuits, equipment damage, fire hazards, and even complete failure of facility operations. The primary causes for these transient overvoltages include lightning strikes, switching operations, and electrostatic discharge. Among these, lightning strikes are the most common source of power surges. Even

indirect effects of a lightning strike can induce a surge voltage. The electromagnetic field created by the lightning current generates resistive and inductive coupling, which can potentially cause severe equipment malfunctions or permanent damage. Industries must integrate surge protection devices and strategies to safeguard electrical and electronic equipment within control cabinets. These devices detect and divert impulse current and transient overvoltages away from sensitive systems, ensuring

that only the required power levels reach critical components. Such protection also helps prevent costly downtime and equipment replacement. This article explores the fundamentals of surge protection devices and design challenges, followed by examples from Littelfuse and Phoenix Contact.

How does surge protection work?

Surge protection devices (SPDs) operate in a high impedance state, functioning as an open circuit. In this state, they maintain electrical isolation between the active conductors and ground, ensuring no connected equipment is affected. However, during transient overvoltage, SPDs switch within nanoseconds to a low-impedance state. This closed-circuit condition allows them to divert excess current to ground, thereby limiting the surge voltage and discharging the associated surge current. Surge voltages can occur between active conductors (normal mode) or between active and protective conductors (common mode). To protect electrical components, SPDs are typically placed in parallel—either between phase conductors or between phase and ground potential—depending on the surge path, as shown in Figure 1.

Figure 1: Parallel installation of SPDs for both normal and common mode surge protection. (Image source: Phoenix Contact)

Nonlinear components inside an SPD This dynamic behavior of an SPD is enabled by the presence of at least one nonlinear component within its design. These components conduct electricity only when the voltage across them exceeds a defined threshold. Common types include metal oxide varistors (MOVs), avalanche breakdown diodes (ABDs), and gas discharge tubes (GDTs).

Among these, MOVs are the most widely used in AC power circuits. Their surge current rating depends on their cross-sectional area and composition. The larger the cross- sectional area, the higher the surge current rating of the device. MOVs are made of zinc oxide grains mixed with other additives. These grains form a network of semiconductor junctions at their boundaries, which act as diodes, allowing current to pass only during overvoltage events.

we get technical

Surge protection in industrial control cabinets

Under normal conditions, MOVs remain in a high-resistance state. When a surge occurs and the voltage crosses a threshold, their resistance drops, enabling them to shunt the surge current to ground. After the event, they automatically return to their high-resistance state. Design challenges with SPDs While SPDs are designed to absorb high-energy transients, repeated exposure to smaller overvoltages on the power distribution system can lead to premature aging and device failure. This occurs when the maximum continuous operating voltage (MCOV) rating is too close to the system’s nominal operating voltage, making the SPD vulnerable to routine voltage fluctuations. To resolve this issue, it is recommended that the MCOV of the device be at least 115% of the nominal system voltage, ensuring the device is unaffected by normal voltage variations in the power distribution system. In some cases, the current magnitude exceeds several hundred thousand amperes. To evaluate the performance of an SPD, the primary benchmark is the nominal discharge current rating, which demonstrates the device's ability to withstand repetitive current surges without damage or degradation.

■ Type 3 devices: Placed close to the load, offering localized protection for sensitive electronics. Littelfuse offers the SPDN-A series of SPDs that are intended for installation at the sub-distribution board downstream from the main panels to protect the branch circuits and connected equipment. For example, the SPDN-A480- 3D (Figure 2), has a nominal voltage of 480 V and is capable of continuously withstanding up to 550 V without degradation. The device features line-to-neutral, line-to-ground, and neutral-to- ground protection, along with the ability to suppress electromagnetic and radio frequency interference. This SPD is designed using multiple

Examples of industrial surge protection devices Surge protection in an industrial setting involves a strategic approach with different types of SPDs installed at various points in the electrical distribution system to reduce surge energy. According to UL 1449, SPDs are classified by installation location: ■ Type 1 devices: Installed very close to the service disconnect. They are designed for the line side of the main overcurrent protective device but can also be used on the load side. ■ Type 2 devices: Located downstream of the service disconnect, protecting against residual surges from external events.

MOVs in a layered structure, enabling a compact design.

Figure 2. Littelfuse’s SPDN-A480-3D surge protection device with an MCOV rating of 550 V in a 3-phase delta configuration (Image source: Littelfuse).

Figure 3. The Phoenix Contact 2907916 PLT-SEC Series Type 3 surge protection device with a nominal voltage rating of 24 V AC/DC (Image source: Phoenix Contact).

Figure 3 shows the Phoenix Contact 2907916 PLT-SEC Series Type 3 SPD that can be placed near sensitive electrical components, such as programmable logic controllers (PLCs) or control units. It is suitable for final-stage protection against residual surges that pass through upstream protection. Additionally, it includes a DIN rail-mounted base and a plug-in protection module and is rated for 24 V AC/DC low-voltage, single-phase circuits. Its remote signaling contact ratings are 250 VAC / 125 VDC, 0.5 A for remote alerts or panel indicators.

Conclusion As industrial control systems become increasingly complex, integration of surge protection devices has become essential. By clamping transient overvoltages, SPDs protect the electronic and electrical components housed within control cabinets. Selecting the correct SPD is vital for meeting the specific requirements of an industrial facility. Key factors in this selection process include the MCOV and the nominal discharge current. A layered protection strategy, utilizing UL Type 2 and Type 3 devices, is crucial for enhancing the resilience of industrial operations.

Sources: https://library.e.abb.com/public/ d2318d61b512403288bf9c438daaf 9d1/1TXH000565C0201_Global_gui de_to_surge_protection_EN_BR.pdf https://www.perle. com/downloads/surge- protectors/5131327_tt_basics_ surge_protection_en.pdf https://www.nemasurge.org/how- spd-s-work/#modes

we get technical

Using a unified cybersecure platform to support comprehensive

industry 4.0 connectivity

By Jeff Shepard Contributed By DigiKey's North American Editors

A unified and cybersecure Industry 4.0 deployment requires multiple levels of connectivity. The first level of connectivity starts on the factory floor with the control of individual devices, including machines and robots, sensors, and traceability solutions. The second level of connectivity extends to mid- level automation with human-machine interfaces (HMIs) and machine-to- machine communication. The highest level of connectivity links with the company’s information technology (IT) and operations technology (OT) systems to coordinate overall logistics and maximize efficiency and productivity. Satisfying diverse connectivity needs requires an automation platform that supports multiple open protocols like EtherCAT, Safety over EtherCAT (also called FailSafe over EtherCAT or FSoE), EtherNet Industrial Protocol (EtherNet/IP), common industrial protocol (CIP) Safety, and IO-Link for connecting machines, machine controls, sensors, vision systems, safety devices, and HMIs. The Open Platform Communications Unified Architecture (OPC UA) protocol is needed to support data consolidation, sharing, and secure visibility across the enterprise. Finally, a software platform is required that integrates configuration, programming, simulation, and monitoring with an intuitive interface, allowing engineers to manage process control, motion, safety, vision, and robotics in one system.

we get technical

Using a unified cybersecure platform to support comprehensive industry 4.0 connectivity

Figure 1: Levels of connectivity used in Industry 4.0 automation systems from IO-Link on the factory floor to MQTT and OPC UA reaching higher-level enterprise systems and the cloud. (Image source: Omron Automation)

This article first presents a diagram of the levels of connectivity in Industry 4.0

factory automation networks, and how OPC UA links the factory to higher-level enterprise networks and the cloud using Message Queuing Telemetry Transport (MQTT) and other standard protocols. It closes with a look at how Omron’s Sysmac Studio software ties it together.

Safety, sensors, and servos At the automation network level closest to the factory floor, sensors, safety controllers, motor drives, and servos are found and have specific connectivity requirements. IO-Link supports intelligent sensing, and EtherCAT links the various motion, I/O, safety, and vision subsystems into a real- time machine network.

automation systems (Figure 1). It then uses product examples from Omron Automation to move through the various levels of automation from IO-Link and intelligent sensing to EtherCAT for vision systems and real-time machine control, EtherNet/IP for

standardized and reused efficiently using program organization units (POUs) defined in IEC 61131 for design and operation. AI-based vision Artificial intelligence (AI) based automated vision systems can boost productivity across a wide array of Industry 4.0 applications like robot guidance, code reading and verification, color inspection, counting, defect identification, optical character recognition (OCR), and optical character verification (OCV), and presence/absence detection. Developing and deploying AI-based vision systems can be a complex and time-consuming activity. Omron’s FH series includes the hardware and software needed to implement various AI-based vision applications quickly. For example, the model FH- 2050 can support two cameras. Additionally, like other models in the FH series, it boasts a wide range of connectivity options, including EtherCAT, EtherNet/IP, Ethernet TCP/IP, PROFINET, serial RS-232C, and universal serial bus (USB), enabling it to fit into many locations in Industry 4.0 factories seamlessly. In the case of mass customization, a hallmark of Industry 4.0 production lines, automated visual inspection can be challenging to implement.

Until recently, experienced human inspectors were required to identify product defects. Today, AI has reached a level of capability where it can recognize object features and defects, ranging from blemishes to scratches, as well as human inspectors. In addition, AI can include machine learning to support continuous improvement and adaptation to new requirements. Servos Servos and drives are an integral part of Industry 4.0 factories. Omron’s 1S servo technology supports units from 50 W to 15 kW. For example, model R88D- 1SN15H-ECT is a 1.5 kW servo drive rated for 200 to 240 Vac single and three-phase input power. It’s compatible with the R88M-1L1K530T-BS2 servo, rated for 1.5 kW and 3,000 revolutions per minute (rpm) with 4.77 Newton- meters (Nm) of torque. Like all 1S servos, this unit features: ■ High-resolution multi-turn 23-bit encoder ■ Direct motor brake control with an embedded relay

I/O units It takes a wide range of I/O units to support the diversity of sensors in Industry 4.0 factories. Omron’s Sysmac NX I/O Units include over 120 models and support a wide range of protocols, including IO- Link for connecting to sensors and EtherCAT and EtherNet/IP for linking with motion, safety, vision, and other controllers. These I/O units also support FSoE and CIP Safety protocols. Safety controllers Safety is a crucial consideration when working with factory automation. Omron offers the NX Integrated Safety Controllers that support robust safety systems that meet PLe according to EN 13849-1 and SIL3 according to IEC 61508, including FSoE connectivity. In addition, EtherNet/IP coupler units like the NX-EIC202 can link NX Integrated Safety Controllers with an EtherNet/IP multivendor network, the NX-series I/O Units, and other safety units. The safety CPU can control up to 128 safety I/O units. The safety units can be used with any combination of standard NX I/O units. Further increasing deployment speed and flexibility, safety programs can be

■ Built-in safety functions

■ Hardwired safe torque off that meets PLe according to EN ISO 13849-1 and SIL3 according to IEC 61508

we get technical

Using a unified cybersecure platform to support comprehensive industry 4.0 connectivity

■ FSoE safe torque off that meets PLd according to EN ISO 13849-1 and SIL2 according to IEC 61508

EtherCAT control network support and EtherNet/IP connectivity for linking to factory automation controllers. They have slots for two option boards providing expanded connectivity, including serial communications and analog I/Os. These controllers fully conform with IEC 61131-3 programming standards to simplify and speed commissioning. Omron’s NX1P is an essential all-in-one controller that can manage advanced motion, vision, safety I/O, networking, and IoT connectivity. For more complex machine control applications that can benefit from up to 254 CIP safety connections, up to 62 axes of motion, 256 EtherCAT nodes, 1 Gbps EtherNet/IP ports, and OPC UA, network designers can turn to the Sysmac NX502 controllers. Advanced machine control The NX502 controllers are suited for use at the EtherCAT and EtherNet/ IP network levels, and they include MQTT, OPC UA, and structured query language (SQL) capability for connecting to the company’s IT and OT systems and the cloud. NX502 controllers have slots for up to four EtherNet/IP (EIP) expansion cards with data Transfer rates up to 1 Gigabit per second (Gbps). Each EIP card creates a

Machine controllers Machine controllers like the NX1P2 series from Omron can fulfill two functions. They can be used to directly control various servos and other machines on the EtherCAT level of real-time machine control, and they can provide a link up to the EtherNet/ IP factory automation level. These controllers support integrated sequence and motion control and connect to up to eight controlled axes using EtherCAT (Figure 2). They also feature

Both the hardwired and FSoE safe torque off meet EN61800- 5-2(STO). A hardwired solution can bring the line to a standstill by cutting main power. FSoE supports more nuanced responses and can send a Safe Operating Stop command, only slowing the motors in the affected area. FSoE can also send a Safe Stop command, stopping the motors when needed.

Figure 2: NX1P controllers can use EtherCAT connectivity to support up to eight axes of motion, like eight 1S AC servo drives. (Image source: Omron Automation)

subnet, increasing the number of machines that can be controlled and segmenting the machine-level network from the database network and the factory-level network. Network segmentation also reduced cyber-attack risk by limiting access to the different subnets. These controllers sit at the apex of the network architecture and support a variety of control, information, and safety functions, including (Figure 3):

■ Control

■ Up to 32 axes of motion with 250 μs cycle time

■ Servo control with up to 64 axes

Figure 3: NX502 controllers (center) can combine all the functions needed to implement Industry 4.0 automation networks. (Image source: Omron Automation)

■ 80 MB program storage

■ 260 MB variable storage

■ Information

■ Up to 10 x 1 Gbps EtherNet/ IP ports for high‐speed, high‐ capacity communications with expansion unit

Human-machine interface The NA series advanced programmable terminal/HMI provides operators and network engineers reliable and convenient access to Sysmac automation devices and networks. These wide- screen terminals have two Ethernet ports supporting simultaneous access to a control device and maintenance activities. They are programmable, making it simple to implement custom user interfaces.

■ OPC UA provides secure connectivity for manufacturing execution systems (MES) and enterprise resource planning (ERP) systems ■ SQL functionality supports fast and reliable direct access to databases and communication of production data ■ MQTT supports direct connection to the cloud and secure data collection

■ Safety

■ Up to 8 CIP Safety networks for network modularization and safety control across production lines ■ Up to 254 FSoE connections for high speed and high- reliability safety in large production lines

we get technical

Using a unified cybersecure platform to support comprehensive industry 4.0 connectivity

These HMIs are available in sizes of 7”, 9”, 12”, and 15” to fit a wide range of application needs. The 12” and 15” models have 1,280 x 800 pixels, while the 7” and 9” models have 800 x 480 pixels. Operators wearing gloves can use their resistive touch screen, which can be made waterproof if needed. The function keys can be programmed to simplify user interactions (Figure 4). Cybersecure software Sysmac Studio includes comprehensive and cybersecure software tools for designing, verifying, and operating industrial networks. It enables network designers to integrate logic, motion and drives, robotics, safety, visualization, sensing, and information technologies. Some key capabilities during design and verification include (Figure 5):

Figure 4: These programmable HMIs feature two Ethernet ports and can be made waterproof. (Image source: Omron Automation)

Figure 5: Sysmac Studio software provides comprehensive support for designing, verifying, and operating Industry 4.0 automation networks. (Image source: Omron Automation)

■ Automatic programming based on truth tables with input, output, and stop conditions of safety devices ■ User-defined function block (FB) to support help files to describe input and output conditions and program functionality; can have different security levels to protect them from unauthorized changes ■ Offline simulation performed on a separate computer without connecting actual hardware ■ Online functional testing of integrated safety functions; test results can be output as a report Sysmac Studio software also supports ongoing operations and maintenance. Downtime is minimized using an SD memory card containing logging settings and safety data logging. This data enables network technicians to efficiently determine the cause of an unexpected system stoppage and take appropriate preventative and corrective measures. The safety unit restores an automatic configuration restart to reduce maintenance: ■ Restore programs and settings are stored on an SD card in the safety unit. When a safety controller unit is replaced, the stored programs and settings can be quickly copied to the new unit.

■ When a safety I/O unit is replaced, automatic configuration restart

automatically downloads the setting data into the new unit.

Conclusion Sysmac automation devices and software from Omron support the complete connectivity needs for Industry 4.0 factory automation networks. Their capabilities extend from IO- Link for connecting to sensors and EtherCAT and EtherNet/IP for linking with motion, safety, vision, and other controllers. They include support for FSoE and CIP Safety protocols. Powerful controllers and software that use OPC UA, SQL, and MQTT are available to link the factory network to the company’s IT and OT systems as well as the cloud.

we get technical

How smart motor controls can maximize resilience and uptime

By Jeff Shepard Contributed By DigiKey's North American Editors

Smart motor controls are needed that can maximize resilience and uptime of machinery in the next generation of Industry 4.0 manufacturing, metals and basic materials processing, mineral extraction and mining, and critical infrastructure like drinking water and wastewater plants.

The motor controls in these applications must be able to control and protect motors

between 75 horsepower (HP) and 700 HP. Comprehensive protection, including overload protection, ground fault protection, and phase imbalance protection, is needed to support resilient operation. They should also include self- diagnostics for contact wear and coil over/under voltage detection with visible indicators to support predictive maintenance and have modular designs for faster servicing to maximize uptime. Compliance with National Electrical Code (NEC), UL, and International Electrotechnical Commission (IEC) short circuit current rating (SCCR) is needed to ensure electrical equipment can withstand high currents without damage and that it’s safe. These motor controls must also comply with IEC 60947-4- 1, which covers the safety of electromechanical contactors and starters, including motor protective switching devices

Figure 1: SCCR calculations begin with individual component ratings (yellow boxes), move up to determine the SCCR of branch circuits (red dashed box), and then consider the SCCR needs of the completed control panel (grey rectangle). (Image source: Schneider Electric)

(MPSD), instantaneous-only motor protective switching devices (IMPSD), and actuators of contactor relays. This article begins with an overview of SCCR requirements. It then takes a deep dive into a recently developed family of smart motor controls from Schneider Electric, including modular contactors and overload relays detailing the operation of the protective functions and how self-diagnostics is implemented. It looks at how those overload relays meet the requirements of IEC 60947-4-1 and presents how the modular design speeds

preventative maintenance. It closes by looking at how two contactors can be used to assemble a reversing assembly, enabling bidirectional control of AC motors. The SCCR is an essential characteristic when specifying a control panel that contributes to overall dependability. It’s used when sizing power components like contractors and conductors. IEC 60947-4-1 details three phases for calculating the SCCR (Figure 1): 1. Identify the SCCR of each protection and/or control component and each block and element in the distribution system.

we get technical

Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56