Motor protection meets smart system design.

Essential motor safeguarding capabilities into scalable, data‑driven control panel designs.

The AB 140ME Motor Protective Switching Device delivers more reliable branch‑circuit protection by combining disconnect capability, magnetic short‑circuit protection, electronic overload protection and manual switching for motor control. Built to safeguard motors from overload, phase loss, and short‑circuit conditions, the 140ME provides dependable protection while maintaining the high electrical performance required for demanding applications.

For manufacturers, the 140ME offers advantages in both performance and ease of use. By consolidating multiple protective and control functions into a single device, it reduces panel complexity and simplifies installation. Operators benefit from clear status indication and predictable trip behavior, making it easier to identify issues, restore operation quickly and maintain consistent uptime. Its compact footprint also helps panel builders optimize space without compromising accessibility or safety.

This device is a key component of Rockwell Automation’s Branch Motor Control & Protection portfolio, working alongside 100‑E Contactors, 140MT Motor Protection Circuit Breakers and E100 Electronic Overload Relays. Together, these devices create a unified motor control architecture that simplifies design, strengthens motor protection and improves coordination across in-panel architectures. This alignment helps deliver consistent performance and a smoother engineering experience from design through commissioning.

With the latest release of the EtherNet/IP In‑cabinet Solution, the 140ME becomes even more powerful. New connectivity through a 100‑E Contactor communication module brings real‑time diagnostics, device health insights and operational data directly onto the EtherNet/IP network. This integration allows manufacturers to monitor motor conditions, identify issues quickly and support predictive maintenance strategies, all while reducing wiring and simplifying panel design. The result is a smarter, more connected motor control ecosystem that scales effortlessly as operational needs evolve.

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@ROKAutomation @ROKAutoEMEA @AllenBradley #PAuto

Power surge protection.

 Voltage spikes are brief events that rarely last more than a few microseconds. In complex systems, however, even seemingly small events can have serious consequences. This is definitely true of industrial automation systems, in which many different devices need to work seamlessly together in order to maintain normal operations. Computers and communications equipment are essential components of many modern automation systems, and are particularly susceptible to power surges from voltage and current spikes because they typically have low dielectric strength. In these systems, serial device servers are key communications gateways that connect the broader Ethernet network with specific serial devices. A power surge that damages this vital communications link will bring the entire process to a halt.

A voltage spike is a momentary extreme burst of electricity in an electrical circuit. This energy spike may be short-lived, but could still be strong enough to seriously damage the electronics. Voltage spikes cause corresponding spikes in the current impulse.

There are many potential sources of power surges. Two of the most common are spikes from lightning and switching surges:

• Lightning: Lightning creates substantial electric discharge at the location it strikes. Lightning that directly strikes a building can clearly endanger its electrical system, but there are other ways for lightning strikes to cause a power surge. For example, when lightning strikes a power transmission line, the effects can cause an equally dangerous voltage spike miles away. Even in locations with infrequent lightning strikes, lightning poses a significant risk and its consequences must be mitigated.
• Switching Surge: There are many malfunctions in electrical equipment that can lead to power surges. Tripped circuit breakers, short circuits, or even power transitions can all create switching surges. These electrical irregularities may be man-made but can cause just as much damage as lightning. A large power substation that regularly cycles on and off generates enough switching surges to threaten sensitive electronic devices.

Gaps in Existing Power Surge Protection.
Industrial automation operators generally understand that power surges pose a serious threat to their systems and take steps to reduce this threat. Not only do power surges damage and destroy equipment, they cause costly interruptions. In the case of serial-to-Ethernet communications, irreplaceable historical data could be lost if the serial or Ethernet ports suffer a power surge.

For a serial device server, there are three major points of weakness that could be damaged by a power surge: the serial line, the Ethernet line, and the power line. Many serial device servers offer surge protection on the Ethernet and power lines to protect against this threat. However, most serial device servers leave the serial line unprotected. As a consequence, the serial line is often the vulnerable chink in a serial device server’s surge protection armor.

Surge Vulnerability in Substations.
Substation automation facilities are at particular risk for power surges because they are highly susceptible to both major sources of voltage spikes. As outdoor facilities, substations are more exposed to lightning strikes. As electric facilities that perform electric transformation and switching, switching surges are also a danger. At the same time, electric substations need reliable serial communications in order to perform essential tasks such as reading power meters. If surge damage occurs on a serial line, then any meter data on the associated line will be lost. This combination of increased risk profile and greater consequences means that robust products with industry-certified surge protection are a must for electric substations. 

 Full Spectrum Surge Protection.
Surge protection is not an option for vulnerable communications links. Effective and comprehensive surge protection reduces downtime and increases system stability by eliminating the most common cause of failure. IEC 61000-4-5 testing is imperative to verify that a device has sufficient surge protection to withstand voltage spikes. IEC 61000-4-5 Level 1 testing is intended for a device that operates in partly protected electrical environments, while IEC 61000-4-5 Level 2 and higher testing certifies that a device can operate in highly electrical environments.

Many manufacturers offer serial device servers with IEC 61000-4-5 rated surge protection on the power and Ethernet lines. However, the same level of integrated surge protection is rare for the serial line. In order to acquire serial line surge protection, device servers are often deployed with additional external surge protection devices. However, this retrofit adds complexity, increases space requirements, imposes additional maintenance costs, and complicates support cases. Industrial automation systems can be complicated enough as it is without an additional requirement to deploy, maintain, and support yet another device just to provide serial line surge protection.

Closing the Gaps in Surge Protection.

Moxa NPort A Series of serial device servers sets itself apart from other solutions with built-in IEC 61000-4-5 rated surge protection on the serial line in addition to Ethernet and power line surge protection. This provides a reliable, resilient serial device server solution in a convenient all-in-one package. With built-in serial line protection, it is no longer necessary to find, test, and deploy an external serial surge protection product. Surge immunity on the serial, Ethernet, and power lines grants the compact, IEC 61000-4-5 certified Nport A series reliability and full-spectrum protection against voltage spikes and electrical noise.

Moxa NPort A Series devices (pictured above right) are 1 to 4 port serial to Ethernet device servers for hazardous locations. They have enhanced surge protection for serial, LAN, and power, and 2 KV isolation for serial signals. They also have rugged screw-type terminal blocks for power and serial connectors, and are C1D2 and ATEX certified for harsh industrial environments.

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@Moxa_Europe @OConnellPR #PAuto #OT/IT #PowerSurge

Undisturbed power.

The MF 320 IEC inlet EMC filter available now from EMIS improves EMI immunity of electronic equipment while adding a safety isolating dual pole switch and dual fusing. 

Designed to supress any undesirable incoming disturbances present on power lines the MF 320 also reduces any system noise being reflected on to the mains supply.

The EMIS MF 320 meets the increasing demands of industrial, medical and ITE equipment to meet EMC regulations. Applications include Automation, Robotics, Motor drives, White Goods, Monitors, Clinical, Cosmetic and Patient Use medical equipment and Energy Meter Test Systems.

Key features include: • Input Voltage - 250/260 VAC @ 50, 60, 400Hz. • Power rating – available in 1A, 3A, 6A, 10A versions. • Operating temperature range - 25°C to +85°C. • Designed to meet – UL 60939-3, CSA 22.2 No. 8-13, IEC 60939-1&2. • Custom designed versions available.

EMIS aims to offer an end-to-end solution to meet industry’s ongoing EMI Challenges. Customers are supported by a very experienced consulting team, a fully equipped Pre-Compliance Lab and a huge safety certified standard product offering of over 2500 part numbers produced in their own very efficient plant.

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@proactivefleet #EMIS #PAuto #Electronics

Monitoring with surge protection.

Modularity, loop disconnect function, and fault monitoring for signal lines up to SIL 3 in accordance with IEC/EN 61508 - these features are combined in the new M-LB-4000 surge protection system from Pepperl+Fuchs. The devices limit induced transients from various causes on signal lines, for example, due to lightning or switching operations. The 2-channel modules support higher plant availability: Since the protective function is completely housed in the plug-in protection module, there is no need to for rewiring during the replacement.

The M-LB-4000 consists of a two-part surge protection and a two-part fault status monitoring system.

The protection module contains all protection components. It can be replaced without tools while the base module remains in operation. The device has a status indicator on the front panel. When pulling the protection module, the relevant signal circuit remains interconnected via the base module mounted on the DIN mounting rail. The disconnection process does not lead to any signal interruption, meaning that a protection module can be replaced without impairing plant operation.

It allows easy commissioning and servicing using a loop-disconnect function and uninterrupted protection module replacement during ongoing operation.

If the protection module is rotated by 180 degrees and plugged in, the signal circuit will be broken via the integrated isolating function. This simplifies servicing work and loop checks and allows insulation tests to be performed during commissioning or repeated testing.

The two components of the fault status module monitor the status of multiple surge protection barriers. The kit consists of two parts; the optical emitter / receiver and the optical deflection unit. If a fault occurs in one of the barriers to be monitored, the optical signal is interrupted and the fault is identified. The fault status module provides an LED status indicator, enabling visual inspection of the surge protection to meet the normative requirements for regular testing. In addition, a status message output is available, so that the block in which the fault occurred can be identified. One fault status module can monitor up to 50 modules.

At 6 mm, the small width of the modules saves space in the switch cabinet. During retrofitting, existing common disconnect terminal blocks can be replaced regardless of space requirements.

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@PepperlFuchsUSA @mepaxIntPR #PAuto

Surge protection.

The introduction of several upgraded versions of Emerson's SolaHD™ surge protective devices and power filters gives users more ways to prevent damage to mission-critical electronics driving the Industrial Internet of Things (IIoT) within their facilities.

Each of the new SolaHD devices has been redesigned to provide protection against the full spectrum of voltage transients and surges that may impair operation of distribution and control panels, factory automation systems, PLCs, and other industrial and machine tool equipment. Offering simple and rugged designs with fewer points of failure, the surge protective devices and power filters combine the strongest aspects of SolaHD legacy designs with entirely new designs and features tailored to the needs of today’s processes. This was achieved through a transformation of the line that includes:

• The SolaHD STFE Elite filter combines SolaHD Tracking technology with UL Listed surge protection and the convenience of DIN mounting. It continuously tracks the input AC power line responding instantly into action upon detecting extraneous high frequency noise and high voltage transients caused by everyday events such as turning on machinery, motors, or equipment.
• To compliment the traditional STV100K (UL Type 2) metal only options, SolaHD is now offering a new smaller footprint tri-mount option, the SPD50K Surge Protective Device (UL Type 1) for branch panel and critical load applications. It can be installed via 3/4-inch NPT, DIN-Rail or bracket mount anywhere in an electrical distribution system for added design flexibility.
• In place of the discontinued STV200K surge protector, SolaHD has introduced a smaller version of its SPD200K that will now include an internal and rotary disconnect and event counter standard. It utilizes enhanced circuitry to better monitor the status of all protection modes, including neutral to ground.
• To replace the phased-out STV400K model, SolaHD has launched a new smaller version of its SPD300K that also includes an internal rotary disconnect and event counter standard. Both the SPD300K and SPD200K deliver continuous protection from damaging voltage transients and electrical noise commonly found at the service entrance or distribution panel.
• To support the water and wastewater processing industries, SolaHD has unveiled three surge protection devices or filters housed in either a NEMA 4X polycarbonate case, standalone housing or encapsulated in stainless steel pipe suitable for severe environments. The STCSLAC12036 replaces the SLAC12036LC control and signal surge, while the STCHSP121BT1RU takes the place of the HSP121BT1RU AC replacement module which can be used standalone in control applications, and the STCSS640362 supersedes the SS64036 surge suppressor.
• Finally, SolaHD has introduced 600V surge options for its SPD200K/300K and SPD50K surge protectors targeting the Canadian market applications.

Machine downtime is the single largest source of lost production, typically accounting for almost 5 percent of factory losses—although many manufacturers lose more. For example, when the cost of equipment replacement and parts, labor, maintenance, delays, sales, and production are added up, downtime can exceed $10,000 per hour. SolaHD surge protectors and power filters help maximize machinery efficiency, productivity, and longevity. Their engineering ideally compliments SolaHD's comprehensive line of power protection and power conversion solutions.

Surge protection.

The new M-LB-2000 system from Pepperl+Fuchs offers surge protection with nothing more than a loop disconnect function for easy maintenance and commissioning, making it ideal for use in applications that only require a minimal specification.

The M-LB-2000 can also be used as a superior alternative to terminal blocks with surge protection. The terminal blocks can be replaced by the 6.2 mm slim modules with no additional space required. The one-piece devices can be mounted on a standard DIN mounting rail, are approved for applications up to SIL 3, and are certified in accordance with ATEX and IECEx up to Zone 1. This makes the M-LB-2000 system the ideal complement to the M-LB-5000 surge protection system - the two-part system that offers diagnostic functions.

The M-LB-5000 with condition monitoring function has patented diagnostics and uses a special algorithm to detect different overload situations that can cause the surge protection functionality to wear out. This improves the availability of the protective function, and therefore the system as a whole, while minimizing maintenance costs. The traffic-light display on each protection module greatly reduces testing work, as the fault can very easily be assigned to a specific signal circuit.

This system also offers considerable advantages over other solutions when it comes to maintenance. For example, the base module on the DIN mounting rail stops the signal from being interrupted when the protection module is disconnected. A protection module can therefore be replaced without affecting plant operation. However, if the signal circuit needs to be intentionally interrupted - for isolation tests during commissioning, for example - the protection module can simply be rotated by 180 degrees and plugged in. In this case, the signal circuit is interrupted by an integrated isolating function.

@PepperlFuchs #PAuto 

Surge protection.

Harting has developed a protective circuit housed within a modular connector in order to protect common signals in the instrumentation and control area. This means that both digital and analogue circuits are securely protected.

Since these signals can be of different types, in addition to a modular combination for I&C signals with common reference potential (generally digital signals), Harting also offers a combination for differential signal transmission or for transmission without a common reference signal.

These signals are generally differential types such as bus interfaces up to 5 MHz or analogue signals such as 0/4-20 mA or 0/2-10 V. Both types – two-channel types for differential signals and four-channel types for signals with common reference potential – can transmit nominal 24 V DC and up to 0.5 A. The protection level is approximately 50 V, depending on the type.

Transients, which can disturb signal circuits and destroy electronic devices, are discharged to the ground via an appropriate spring element and the grounded Han-Modular® hinged frame. This ensures interference-free transmission of the signal.

When used correctly, the surge protection modules reduce the number of operating faults, increase the service life of the production line and ultimately increase plant uptime. Additional costs are avoided and the profitability of the production plant is maintained.

@HARTING_Group #PAuto 

Protecting I/O connectors from surges.

Modern highly automated production plants rely on industrial connectors for the supply of energy, the communication of data and, above all else, the reliable and efficient transmission of signals from measuring, control and regulation technology. Here, transmission quality depends on the performance of both the key interconnection devices for inputs and outputs in the central electrical control cabinet and the protective devices applied within signal circuits.

Catastrophic damage to electronic circuitry
as a result of voltage transient effects

Minimal downtimes for machines and plants are a decisive factor in maximising productivity and as a result directly affect a company’s operating profitability level. In particular, unpredictable failures such as those caused by voltage transients in control circuits can have a critical negative impact on plant operation. Even relatively small voltage peaks (i.e. anything higher than the maximum continuous operating voltage of the protected device) can cause catastrophic damage to some of the most up-to-date electronic components.

In order to avoid plant stoppages and the associated production disruption that could arise in such failure conditions, electrical control cabinet designers and builders normally integrate separate DIN-rail mounted surge arrester devices to offer in-line protection to the most sensitive circuits. These typically consist of multiple I/O sensors and switches which are generally installed in the control cabinet, each taking up around 6-12 mm of DIN rail mounting space. More significantly, they require time and wiring effort, and involve noteworthy extra cost.

To address this challenge, Harting has developed an interesting new approach that saves important internal control cabinet space and enables a potentially more cost-efficient higher density cabinet design. This solution moves the in-line surge protection circuitry out of the cabinet and integrates it directly into the I/O interlinked connector. This is achieved through an innovative new surge-protection module that has been added to the well-known Han-Modular® range of connector inserts. As a result, potential overvoltage transients are effectively stopped at the cabinet wall.

The Harting Han® Surge Protection module is available in two different versions to allow protection for both digital and analogue binary I/O sensor circuits: a “common mode” E-Type asymmetrical voltage type, for binary signals with common ground-like digital circuits and a “differential mode” symmetrical voltage version, for closed signals like analogue circuits. Both versions have integrated protective circuit designs, as developed by surge protection specialist partner Dehn + Soehne to ensure total fail-safe operation, independent of the cause of failure within the surge protection module.

The transients, which can interrupt signal circuits and destroy electronic devices, are discharged to ground within the connector via an innovative spring element that makes conductive contact with the Han-Modular® hinged frame, which holds the modules in position. For the correct discharging of the signals, it is essential that the frame is connected with the ground.

Typical applications for the “common mode” type include protecting digital I/O sensors such as inductive or ultrasonic proximity switches, often used in general factory automation production environments. The “differential mode” type is often used in industrial manufacturing sectors including chemical, pharmaceutical and food & beverage processing, as well as wind energy.

In conclusion, by integrating Harting Han® Surge Protection modules into panel mounted I/O connectors, it becomes possible to effect significant improvements in the cost-effective design flexibility of electrical control cabinets. Not only are potentially damaging transient voltage surges prevented in signal circuits, but if very high voltage transients such as lightning strikes occur, any possible EMI/RFI interference is prevented from being transmitted over internal cabinet wiring. This prevents the interference reaching the DIN rail-mounted surge arresters and possibly affecting sensitive internal electronic control circuits. The Harting Han® Surge Protection module is the first such smart module that can be integrated into a panel-mounted sensor circuit I/O connector, with its modular connector design also allowing for easy replacement at end-of-life.

 @HARTING  #PAuto 

Narrow surge protection!

With the Termitrab complete product range, Phoenix Contact now offers the narrowest surge protective devices on the market. They are suitable for measurement and control applications starting from an overall width of just 3.5 mm. This means that the protective devices can protect up to 572 signals against surge voltages on just one metre of DIN rail.

The integrated disconnect device ensures safe behaviour in the event of overload. It signals the status on each individual protective device mechanically without auxiliary power.

Optional remote signalling modules monitor the status of up to 40 neighbouring surge protective devices by means of a photoelectric barrier. Installation is simplified as a result: no additional wiring or programming is required for the protection modules.

Protective devices in a narrow design, products with protective plugs that can be tested, signalling, and optional remote signalling modules can be selected according to your specific requirements thanks to the tailor-made product range.

The surge protective devices are available with Push-in connection technology as well as screw connection. Versions are also available with innovative knife disconnection and for Ex applications.

@PhoenixContact  #PAuto 

Surge Protection.

Diagnostics and modularity with an installation width of just 6.2 mm: These features are combined in the new M-LB-5000 surge protection system from Pepperl+Fuchs. By offering these features, the single-channel modules support increased plant availability and optimize total operating costs.

The patented diagnostics of the M-LB-5000 with its intuitive and easy-to-read traffic-light display minimizes testing costs in accordance with EN 62305-3 and allows condition monitoring. The green light on the protection module indicates that there is full protection and sufficient operating reserve. The yellow LED indicates that the protection module has reached 90 % of its lifecycle, but the signal circuit is still protected. The protection module should be replaced when maintenance is next performed. If the indicator is red, the protection module is permanently damaged and protection has been lost. The protection module should be replaced immediately to prevent damage during the next overvoltage condition.

This setup ensures that the protection modules are always replaced at the ideal time. This improves the availability of the surge protection, and therefore of the system as a whole, and at the same time minimizes maintenance costs. The status of the protection modules can be integrated into the control level via the signaling contacts of the function modules and via the Power Rail.
The modular system allows easy commissioning and maintenance using a loop-disconnect function as well as uninterrupted protection module replacement during operation.

When you pull the protection module, the relevant signal circuit remains interconnected via the base module mounted on the DIN mounting rail. The disconnection process does not lead to any signal interruption, meaning that a protection module can be replaced without impairing plant operation.
If the protection module is plugged in at an angle of 180 degrees, the signal circuit will be broken via the integrated isolating function. This simplifies maintenance work as well as loop checks and allows insulation tests to be performed during commissioning or repeated testing.

At 6.2 mm, the small width of the protection modules saves space in the switch cabinet. Disconnect terminal blocks can be avoided: During retrofitting, existing common disconnect terminal blocks can be replaced regardless of space requirements.

@PepperlFuchs #PAuto

Surge suppressor Kit.

A surge suppressor kit is now available for use with Moore Industries’ field-installed instruments enclosed in our BH and SB housings. The kit is approved for use in Explosion Proof applications in the United States/Canada (sCSAus) and Australia/New Zealand (ANZEx).

The surge suppressor exceeds Severity Level 4 of IEC 61000-4-4, providing 3kA (8/20μsec) of surge protection stopping failures due to lightning, spikes and overvoltage surges while minimizing other electrical noise. This suppressor allows HART signals to pass through and therefore can be used to suppress or protect both analog and HART digital/analog signal lines.

This surge suppressor can be used with Moore Industries’ temperature and signal transmitters, signal isolators and signal converters and is easy to install and wire.

This is the latest addition to the family of surge suppressor solutions available from Moore Industries. Our other suppressors include:

·       DIN-Plug Surge Suppressor: Compatible with any Moore Industries DIN unit with a two-terminal header. This suppressor provides lightning-fast response time to stop failures due to lightning, spikes, and overvoltage surges while minimizing other electrical noise.

·       Data Line Rail-Mount Surge Suppressor: Designed to protect digital signals on your RS-422 and RS-485 communications lines. It is compatible with any top-hat or “G” type DIN-rail mounting style.

·       AC Wire-In Surge Suppressor: Provides sub-nanosecond protection for 220VAC process power lines and meets Severity Level 4 of IEC 61000-4-4 and 61000-4-5.

 @MII_Worldwide #Pauto #Ex

Protecting computers in harsh environments

B&B Electronics has expanded its family of industrial-grade USB port protectors with the small-form-factor, affordable USBSSP2 “USB Sentinel” USB 3.0 surge suppressor. Unlike typical non-portable or “pass-through-panel” USB surge protection devices, B&B Electronics’ USB Sentinel is compact (4.5 x 1.22 x 0.96 inches, 11.4 x 3.1 x 2.5 cm) and portable, connecting in-line between the computer and the peripheral device to protect it from the surges, spikes, and electrostatic discharge (ESD) that can occur when connecting computers to equipment in the field and factory. With a wide (0 to 80°C) operating temperature, advanced heavy industrial emissions standards and an EN61000-6-2 heavy industrial rating, the USB Sentinel is small enough to tuck into a pocket or a laptop bag, yet tough enough to stand up to repeated use in harsh environments.

The USB Sentinel is a passive device and provides fast, 20 microsecond clamping of surges -- up to 700 volts on the data lines and 1000 volts on the power lines -- without interfering with normal USB 3.0 connectivity. It is also backwards compatible with USB 2.0, providing a single USB surge suppression solution. The device is transparent to the operating system, host computer or hub, and it requires no drivers.

This suppressor is suitable for field service technicians, as well as fixed installations in industrial automation, instrumentation, security, kiosks, point-of-sale and laboratory market applications.

The USB Sentinel includes a USB 3.0 cable and carries a lifetime warranty.

• Datalink Communications is Distributor/Agent for B&B Electronics products in Ireland. (see B&B Representation in Ireland announced).

Surge protector eliminates threat of power crossover

The new SSP self-healing surge protector from MTL offers state of the art surge protection with the additional features of AC fault withstand capability and current limiting protection to our traditional and proven hybrid surge technology, adding yet another layer of protection.

The product is suitable for all general Process I/O applications and higher voltage signal applications for SCADA run over private wire networks and is designed to eliminate the most common cause of surge protection device failures (continuous overvoltage/over current conditions) whilst adding current limiting protection to the circuit.

The use of Surge Protection Devices on communication lines has increased significantly over the last number of years. However if the communication lines are subjected to induced AC power or AC power-cross, the surge protector can pose possible safety hazards. In these circumstances, the SSP surge protector will respond and draw AC current providing over current protection to the wiring, the load and the loop equipment.

The SSP’s self-healing capability incorporates circuitry to mitigate the hazards of induced AC or AC power-cross up to 240Vrms by stopping the flow of current in milli-seconds to prevent surge protector and wiring damage. Once the AC power is removed, the SSP will automatically begin normal operation.

The single loop design makes the SSP series resilient to sustained over-voltages caused by earth faults and power faults and is packaged in the well-known IOP/SLP enclosure giving a wider range of performance offering.

Surge protection devices preserve solar PV investment

Transient overvoltage protection without backup fuses safeguards quality and lifespan of vital solar energy components whilst maintaining continuity of production

Carlo Gavazzi has extended its solar energy portfolio with new surge protection devices that provide backup protection without internal fuses. The innovative DSF surge arrestors embody a special internal backup that ensures they remain safe at the end of varistor life, thus ensuring the safest transient overvoltage protection for combiner boxes in photovoltaic systems.

DSF surge arrestors comply with new and emerging standards for DC-side surge protection in PV systems, in particular the new French UTE C 61-740-51 and future EN 50539-11As norms.

In addition, they extend the Carlo Gavazzi product family, with three DSF models taking the maximum nominal voltage up to 1200V DC. Available in two- or three-pole configurations, the devices provide both differential and common-mode protection.

Innovative built-in technologies cater for both long-duration temporary overvoltage and instantaneous surges lasting microseconds. The former is addressed by a path combining a current limiter with varistor, whilst faster events are routed to a path with varistor and gas tube surge arrester.

Their innovative technology protects internal varistors from the leakage current that could damage and age them when the nominal DC voltage of the plant is temporary exceeded -  for example in  mornings when the solar panels are cold or in the case of wrong connections. When the varistor nears its end of life, DSF technology ensures the arrester is intrinsically safe with regard to short-circuit behaviour.

DSF arrestors are based on removable cartridges, which can be replaced without leaving the installation unprotected. Exhausted cartridges are indicated by a red optical window on the front panel and a voltage-free contact is provided for remote function monitoring.  Internal wiring and labelled terminals contribute further to quicker, simpler installation and maintenance.

The devices are provided ready-assembled for DIN-rail mounting and come with CE marks as well as UL1449 3rd Edition approval.

UPS system solution for an offshore platform

An Uninterruptible Power Supply is mandatory on oil rigs: for safety reasons, the signal lighting must be operational at all times. Tasked with designing a UPS solution for an offshore rig off the African coast, R. STAHL was faced with three challenges. The UPS system not only required protective measures against explosive atmospheres, but also had to be adapted to the great heat and maritime climate at the rig's location.

Explosion-protected UPS systems from R. STAHL ensure a fail-safe power supply on offshore platforms by means of a battery unit

Due to very high ambient temperatures, the explosion-protected enclosure was fitted with a heat sink and a fan

The Ex UPS guard ensures charger and battery monitoring which is explicitly required in Ex Zone 1

The distributor solution with a safe parallel feed, which ensures the continuous power supply for the lighting, is also suitable for hazardous areas

Complete blackouts or malfunctions in the mains power supply, such as frequency fluctuations or overvoltages caused by lightning strikes, must be safely bridged on oil rigs. Above all, functioning signal lights are not only essential for smooth operation on the rig, but also for the safety of all nearby ships and airplanes. Therefore, the position lights must not fail under any circumstances. The platform, which is situated off the African Atlantic coast and whose cavern is currently being used as a temporary store for natural gas, is usually supplied by means of a solar power plant. A battery-powered emergency grid was installed in parallel. In addition to the power supply unit, R. STAHL assembled further energy distribution components from its modular kit for UPS system solutions.

Beautiful weather, rugged environment
In addition to explosive atmospheres occurring occasionally (Ex Zone 1), the tropical climate and sea air had to be taken into account. The temperature on the platform often exceeds 35 °C, and occasionally reaches peaks of 50 °C. At such ambient temperatures, the operation of the charger for the UPS batteries, which generates a great deal of power loss, required special measures. In order to prevent overheating, R. STAHL installed the battery charger in the largest available CUBEx enclosure. Several special features ensure heat dissipation: by means of a patented cold plate technology, the heat is directly evacuated from the protective enclosure. The heat sink is attached to the side of the enclosure, allowing for easy access to the CUBEx unit during maintenance.

Special features create turbulence
A stainless steel fan for hazardous areas with a motion monitoring function, which is installed above the enclosure, facilitates heat dissipation. The fan also had to be adapted for use in Zone 1 under extreme environmental conditions. The forced cooling is controlled and monitored by an intelligent control system: the operating mode of the fan is adjusted depending on the current ambient temperature. Thanks to these measures, a maximum power loss of 1,000 W can be compensated in addition to the amount dissipated through the enclosure surface by default. The considerable amount of exhaust heat generated by charging the batteries can thereby be released to the environment without compromising the operation of the charger.

Like in all other UPS solutions from R. STAHL, the required explosion protection for Zone 1 is ensured by a special feature which is unique on the market: an integrated Ex UPS guard monitors the functions of the battery charger and the batteries, which are also installed within the Ex zone, according to the ATEX directive and according to IEC/EN 60079 ff, thereby allowing for safe operation.

Continuous lighting with a double power supply
In order to ensure a continuous power supply for the lighting, R. STAHL installed a distribution panel with a safe parallel feed from the standard power supply and the emergency grid. The lighting distribution panel features two interlocked inputs. Additionally, each outgoing line is separately monitored for ground faults. All functions can be activated from the outside, and the status of each outgoing line is clearly indicated by the position of the handle. By installing a combination of CUBEx flameproof enclosures (Ex d) and enclosures with increased safety (Ex e) connection chambers, R. STAHL was able to implement a very compact, weight-optimised system within the limited installation space on the offshore platform. All outside metal parts of the seawater-resistant CUBEx enclosures are made from SS316 stainless steel. This material requires no further surface treatment for use in maritime environments.

100% process safety in hazardous areas: Modular UPS solutions in detail
UPS solutions component range includes battery chargers, various explosion-protected rechargeable batteries (lead gel, NiCd, NiMH), charge monitoring technology including alarm annunciators, DC power distributors and inverters for various performance classes up to 3,000 VA. Additionally, R. STAHL provides a wide range of explosion-protected enclosures, such as the GUBox series which features Ex e connection chambers. R. STAHL also provides modules with user-specific explosion protection types as required.

Fieldbus surge protection

MTL Instruments has released a new Surge Protection Device (SPD) that can be retrofitted to FOUNDATION™ fieldbus systems. The FS32 prevents surges and transient over-voltages conducted along the Trunk, or Spurs, of fieldbus systems from damaging the associated electronics such as terminators, spur blocks and the bus control equipment. Designed to fit MTL’s latest fieldbus products to protect spurs, the FS32 can also be used to protect spurs on Megablock wiring hubs. In addition, the plug-in format makes the product easy to retrofit, and the small footprint assists in the reduction of the size of junction boxes.

The multi-stage hybrid surge protection network at the heart of the FS32 uses a combination of solid state electronics, and a gas filled discharge tube, to provide surge protection up to 20kA. This impressive surge protection circuit is designed to exhibit exceptionally low line resistance, and has negligible voltage drop to the spurs.

In operation the FS32 does not adversely affect the performance, or operation, of the fieldbus or connected equipment. The FS32 allows signals to pass with little attenuation, whilst diverting surge currents safely to earth (ground) and clamping output voltages to safe levels. Fully automatic in operation, the FS32 device reacts immediately to ensure that the equipment is never exposed to damaging surges between lines or the lines to earth (ground). Reacting instantaneously, the FS32 redirects surges safely to earth (ground) and then resets automatically.