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Isolated probing tech for fast-switching power device testing

Keysight Technologies has developed an optically isolated differential probing family dedicated to enhancing efficiency and performance testing of fast-switching devices such as wide-bandgap GaN and SiC semiconductors. Validation of floating half-bridge and full-bridge architectures commonly used in power conversion, motor drives, and inverters requires measurement of small differential signals riding on high common-mode voltages. This measurement can be challenging due to voltage source fluctuations relative to ground, noise interference, and safety concerns.
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Protect sensitive electronics in explosive environments with new aluminum ATEX Cabinet Cooler Systems

EXAIR's ATEX Cabinet Cooler^® Systems deliver a powerful and affordable solution for keeping electrical enclosures cool in hazardous ATEX classified areas -- and they're now available in durable aluminum construction. Engineered for use in Zones 2 and 22, these coolers are UL tested, CE compliant, and meet stringent ATEX standards for purged and pressurized enclosures. With cooling capacities up to 5,600 Btu/Hr., ATEX Cabinet Coolers are ideal for preventing overheating in electrical cabinets. EXAIR offers a comprehensive lineup of systems.
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PLC handbook chock full of must-know information

Automation-Direct's Practical Guide to Program-mable Logic Controllers Handbook has been improved with tons of new need-to-know info, making it a more comprehensive guide to the world of PLCs. Besides covering the basics of PLC history, PLC hardware, and PLC software, this guide takes you deeper into the ever-changing world of PLC communication, the importance of feedback loops, cyber security, and many other areas that are a must-know for any PLC novice or seasoned automation professional.
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Haptic feedback prototyping kit from TDK

Get your customers to feel the difference your products make. TDK has released a development starter kit for fast haptics prototyping. It gives mechanical designers and engineers first impressions of the haptic feedback using PowerHap piezo actuators, shows how the mechanical integration works, and provides a reference design. Applications include automotive, displays and tablets, household appliances, vending machines, game controllers, industrial equipment, and medical devices.
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Mini ESD preset torque screwdriver

Need precision fastening with ESD protection at the smallest torque levels? Mountz has you covered. The new FG Mini ESD Preset Torque Screwdriver is built for low-torque, high-precision tasks. Its compact design makes it ideal for tight spaces and small fasteners, while delivering the same reliable control and ESD protection users have come to expect from Mountz. Two models available: FG25z (3 to 25 ozf.in, 2 to 17.7 cN-m) and FG50z (20 to 50 ozf.in, 14.1 to 35.3 cN-m).
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Laumas load cells and electronics from AutomationDirect

Automation-Direct has added Laumas precision-engineered load cells, transmitters, and accessories that deliver reliable performance in industrial weighing and force measurement applications. The FCAL series high-precision bending beam load cells are ideal for low- to mid-capacity systems. CTL series load cells are designed for both tension and compression, with excellent linearity. The CBL series low-profile compression load cells are perfect for space-limited applications. Laumas load cell transmitters are available too for precise monitoring and control. Very good pricing.
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Engineer's Toolbox: What is ground loop feedback?

Improper grounding can create problems in data logging, data acquisition, and measurement and control systems. One of the most common problems is known as ground loop feedback. Experts at CAS DataLoggers run through five ways to eliminate this problem.
Read the full article.

What is a braking resistor?

According to Automation-Direct, "Braking resistors don't actually provide braking directly -- rather, they allow a drive to stop a loaded motor faster." Why is this important? Protect your AC or DC drive system from regenerative voltage that can create an over-voltage fault on the drive -- especially with high inertial loads or rapid deceleration.
View the video.

New Digital Static Meter: Precise measurement, easy use

Static electricity isn't just a nuisance; it's a serious threat to manufacturing efficiency, product integrity, and workplace safety. Unchecked static can lead to costly downtime, product defects, material jams, and even hazardous shocks to employees. If static is interfering with your processes, EXAIR's upgraded Model 7905 Digital Static Meter offers an essential first step in identifying and eliminating the problem. With just the press of a button, this easy-to-use, handheld device pinpoints the highest voltage areas in your facility, helping you diagnose static issues before they become a problem.
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New laser cutting modulating strategy tested with Mikrotron high-speed camera

Modulating a laser beam's intensity distribution optimizes energy delivery to the process zone, resulting in better cutting speed, cut edge quality, and cut kerf geometry. Scientists in Belgium have come up with a new method that they say produces better cutting results.
Read the full article.

All-in-one embedded PLC based on Raspberry Pi 4 -- build control applications

The new PLC CPI-PS10CM4 from Contec Co. is a compact embedded programmable logic controller (PLC) that is loaded with CODESYS, the world's most widely used software PLC. This product uses Contec's original single-board computer, which is based on Raspberry Pi's latest embedded module, the Compute Module 4 (CM4). By using the wide range of peripheral devices for Raspberry Pi, such as Contec's CPI Series, you can build various control applications in a PLC language that complies with the IEC 61131-3 international standard.
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Torque sensors for fastening applications and more

Saelig Company has introduced the Sensor Technology SGR525/526 Series Torque Sensors to provide precision torque monitoring that is critical for performance and safety. The square drive design (for applications with non-cylindrical shafts) allows for seamless integration into power tools, test rigs, industrial machinery, and precision fastening applications, ensuring superior torque measurement without the need for additional adapters or modifications. The SGR525 offers torque measurement only, while the SGR526 provides torque, speed, and power measurement using a 360-pulse-per-revolution encoder. Industries include automotive, aerospace, manufacturing, and research and development.
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Wide-angle camera optimized for larger, faster conveyor belts

Wider conveyor belts operating at higher speeds are now commonplace in modern logistics. To keep up, SVS-Vistek is offering a cost-effective alternative to multi-camera systems with its fxo901CXGE 10-GigE color camera featuring the Sony IMX901-AQR wide-aspect global shutter 16.4-megapixel CMOS sensor. Unlike standard cameras, this unit captures targets in a wide field of view while maintaining high resolutions. The 4:1 horizontal aspect ratio allows one fxo901CXGE to replace an entire multi-camera system, removing the need for image synchronization.
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Handheld thermal imager cuts diagnostic time

The FLIR TG268 is a next-generation thermal imager that provides professionals in the utility, manufacturing, electrical, automotive, and industrial sectors with a lightweight, handheld, affordable condition monitoring tool. Latest enhancements include higher temperature ranges, improved resolution, and larger data storage capacity. Go beyond the restrictions of single-spot IR thermometers to view and evaluate hot and cold spots that may signify potentially dangerous issues. Accurately measure temps from -25 to 400 C. Native thermal images improved with Super Resolution upscaling.
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SOLIDWORKS 2025: Sheet metal design top features from an expert

Find out what's new in SOLIDWORKS 2025 when it comes to sheet metal and weldments, and learn some valuable tips and tricks along the way from TriMech. Topics covered include copying cut list properties, bend notches, tab and slot enhancements, groove beads (a new type of weld bead), performance enhancements, and more. When you're done, check out TriMech's full YouTube channel filled with educational material.
View the video.

Heat engine cell with no moving parts is as efficient as a steam turbine

A thermophotovoltaic (TPV) cell (size 1 cm x 1 cm) mounted on a heat sink designed to measure the TPV cell efficiency. To measure the efficiency, the cell is exposed to an emitter, and simultaneous measurements of electric power and heat flow through the device are taken. [Credit: Photo by Felice Frankel]

 

 

 

 

By Jennifer Chu, MIT

Engineers at MIT and the National Renewable Energy Laboratory (NREL) have designed a heat engine with no moving parts. Their new demonstrations show that it converts heat to electricity with over 40% efficiency -- a performance better than that of the average turbine-based heat engine system efficiency in the United States.

The heat engine is a thermophotovoltaic (TPV) cell, similar to a solar panel's photovoltaic cells, that passively captures high-energy photons from a white-hot heat source and converts them into electricity. The team's design can generate electricity from a heat source of between 1,900 to 2,400 C, or up to about 4,300 F.

The researchers plan to incorporate the TPV cell into a grid-scale thermal battery. The system would absorb excess energy from renewable sources such as the sun and store that energy in heavily insulated banks of hot graphite. When the energy is needed, such as on overcast days, TPV cells would convert the heat into electricity, and dispatch the energy to a power grid.

With the new TPV cell, the team has now successfully demonstrated the main parts of the system in separate, small-scale experiments. They are working to integrate the parts to demonstrate a fully operational system. From there, they hope to scale up the system to replace fossil-fuel-driven power plants and enable a fully decarbonized power grid, supplied entirely by renewable energy.

"Thermophotovoltaic cells were the last key step toward demonstrating that thermal batteries are a viable concept," says Asegun Henry, the Robert N. Noyce Career Development Professor in MIT's Department of Mechanical Engineering. "This is an absolutely critical step on the path to proliferate renewable energy and get to a fully decarbonized grid."

Henry and his collaborators published their results April 13 in the journal Nature.

Jumping the gap
More than 90% of the world's electricity comes from sources of heat such as coal, natural gas, nuclear energy, and concentrated solar energy. For a century, steam turbines have been the industrial standard for converting such heat sources into electricity.

On average, steam turbine systems reliably convert about 35% of a heat source into electricity, with about 60% representing the highest efficiency of any heat engine to date. But the machinery depends on moving parts that are temperature limited. Heat sources higher than 2,000 C, such as Henry's proposed thermal battery system, would be too hot for turbines.

In recent years, scientists have looked into solid-state alternatives -- heat engines with no moving parts that could potentially work efficiently at higher temperatures.

"One of the advantages of solid-state energy converters are that they can operate at higher temperatures with lower maintenance costs because they have no moving parts," Henry says. "They just sit there and reliably generate electricity."

Thermophotovoltaic cells offered one exploratory route toward solid-state heat engines. Much like solar cells, TPV cells could be made from semiconducting materials with a particular bandgap -- the gap between a material's valence band and its conduction band. If a photon with a high enough energy is absorbed by the material, it can kick an electron across the bandgap, where the electron can then conduct, and thereby generate electricity -- doing so without moving rotors or blades.

To date, most TPV cells have only reached efficiencies of around 20%, with the record at 32%, as they have been made of relatively low-bandgap materials that convert lower-temperature, low-energy photons, and therefore convert energy less efficiently.

Catching light
In their new TPV design, Henry and his colleagues looked to capture higher-energy photons from a higher-temperature heat source, thereby converting energy more efficiently. The team's new cell does so with higher-bandgap materials and multiple junctions, or material layers, compared with existing TPV designs.

The cell is fabricated from three main regions: a high-bandgap alloy, which sits over a slightly lower-bandgap alloy, underneath which is a mirror-like layer of gold. The first layer captures a heat source's highest-energy photons and converts them into electricity, while lower-energy photons that pass through the first layer are captured by the second and converted to add to the generated voltage. Any photons that pass through this second layer are then reflected by the mirror, back to the heat source, rather than being absorbed as wasted heat.

The team tested the cell's efficiency by placing it over a heat flux sensor -- a device that directly measures the heat absorbed from the cell. They exposed the cell to a high-temperature lamp and concentrated the light onto the cell. They then varied the bulb's intensity, or temperature, and observed how the cell's power efficiency -- the amount of power it produced, compared with the heat it absorbed -- changed with temperature. Over a range of 1,900 to 2,400 C, the new TPV cell maintained an efficiency of around 40%.

"We can get a high efficiency over a broad range of temperatures relevant for thermal batteries," Henry says.

The cell in the experiments is about one square centimeter. For a grid-scale thermal battery system, Henry envisions the TPV cells would have to scale up to about 10,000 sq ft (about a quarter of a football field), and would operate in climate-controlled warehouses to draw power from huge banks of stored solar energy. He points out that an infrastructure exists for making large-scale photovoltaic cells, which could also be adapted to manufacture TPVs.

"There's definitely a huge net positive here in terms of sustainability," Henry says. "The technology is safe, environmentally benign in its life cycle, and can have a tremendous impact on abating carbon dioxide emissions from electricity production."

This research was supported, in part, by the U.S. Department of Energy.

Published May 2022

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