Using Imaging Equipment to Locate Issues

Electronic performance is affected by temperature, with heat sources inside and outside a device or system. High-power amplifiers exhibit rises in temperature from the heat of semiconductors and must be equipped with cooling for safety and longevity. Other electronic designs can suffer performance degradations when placed too close to heat sources or even when exposed to sunlight. Fortunately, the temperatures of electronic equipment can be measured quickly and accurately without making physical contact, with the aid of infrared (IR) temperature sensors and cameras among other tools. A variety of IR cameras and thermal imagers are available with many useful features from Axiom Test Equipment, compact enough to fit the tightest places.

These IR cameras and thermal imagers, as well as acoustic and ultraviolet (UV) imagers, can be used to detect temperature overloads in electrical and mechanical equipment. Thermal cameras and imagers detect IR radiation from a target or device under test (DUT) within the camera’s field of vision (FOV). Captured IR radiation data is processed into a thermal profile for a DUT to help a tester identify hotspots, material problems such as poor insulation, or even faulty interconnections.

IR cameras are typically designed for small size and portability to reach tight spots and remote test locations. They can operate for several hours on a rechargeable battery, typically a lithium-ion (Li-ion) battery. IR cameras are capable of high-resolution imaging, showing results on built-in liquid-crystal-display (LCD) screens (although higher resolution is often possible by connecting to a larger, external display screen). Many IR cameras are multifunction testers, combining thermal and optical images to show precise locations of a thermal profile on a DUT. Smaller IR cameras are useful for remote thermal imaging by drones or unmanned aerial vehicles (UAVs). They can be useful for identifying thermal issues in housing developments or fires in national forests.

IR of Interest

Choosing a thermal imaging camera can take time. Although small, these digital cameras often provide a host of functions in addition to their thermal characterization capabilities. Basic capabilities for IR cameras include their temperature measurement range, operating temperature range, temperature measurement accuracy, the distance-to-spot (D:S) ratio or distance to a target to be measured, the size of a target, and the operating time with a rechargeable battery. In addition to these basic parameters, computer interfaces and wireless connectivity can add to a thermal imaging camera’s usefulness.

As an example, the FLIR E8-XT IR camera has a temperature measurement range of -20 to +550°C (-4 to +1022°F) with ±2°C (±3.6°F) accuracy, assuming the camera itself is used within an operating temperature range of +15 to +50°C (+5 to +122°F). A member of the company’s FLIR Ex-Series™ IR cameras, it employs a focal plane array (FPA) IR detector to achieve 320 × 240 pixel IR measurement resolution. Measurement results appear on a 3-in. LCD screen.

The IR thermal camera is small, at 9.6 × 3.7 × 5.5 in. (244 × 95 × 140 mm), and weighs just 1.27 lb. (0.57 kg). It has a 45 × 34 deg. FOV with 2.6-mrad spatial resolution. As with the other models in the series, it employs the company’s Multi-Spectral Dynamic Imaging (MSX®) technology to add visible light images to detected thermal images for ease in identifying hotspots. The camera includes Wi-Fi capability for communications to similarly equipped laptop computers and other wireless devices and is aided by the company’s FLIR Tools® Mobile software to speed the processing of thermal data. It operates for about 4 h on a fully charged Li-ion battery.

The Fluke Ti480 PRO IR camera reads a target’s temperatures from -10 to +1000°C (-14 to +1832°F) with ±2°C accuracy. It has 0.025°C sensitivity to temperature differences. The IR camera has standard resolution of 640 × 480 pixel and “SuperResolution” high-resolution mode with 1280 × 960 pixel resolution. It features interchangeable “smart” lenses, including 2× and 4× telephoto lenses for focusing on different-sized images, at distances as close as 15 cm. With an FOV of 34 × 24 deg., The IR camera has an FOV of 34 × 24 deg. and saves measurements to an SD card. It incorporates Wi-Fi connectivity and runs for 2 to 3 hours on rechargeable Li-ion batteries.

Fluke also performs acoustical imaging, such as from 2 to 100 kHz in the model II910 Precision Acoustic Imager. It has a wide dynamic range and can measure sound pressure levels (SPLs) as high as 135.5 dB. The imager has a detection range of 1.6 to 393.0 ft. (0.5 to 120.0 m) and FOV of 63 ± 5 deg. Its built-in digital camera has 1280 × 800 pixels resolution and shows results on a 7-in. LCD touchscreen.

To detect temperature corona images for a scanned object, the Sonel Test & Measurement UV-260 is a portable ultraviolet (UV) camera. Ideal for inspecting high-voltage (HV) utility lines, it has built-in Global Positioning System (GPS) capability for detailing the location of a power-line fault. Although not characterized for temperature readings in the manner of IR cameras, it can detect UV energy across a range of 240 to 280 nm within a tight FOV of 5.5 × 4.0 deg. and turn those measurements into thermally representative white, red, and blue corona colors to indicate heat emissions from a target. Data can be stored on an SD card and results shown on a 5.7-in. color touch-screen LCD. The display screen can be folded for safe transport. Warnings of UV events can be by means of the LCD or audio alarms. The UV camera has an operating temperature range of -10 to +50°C (+14 to +122°F), is 9.4 × 6.5 × 3.6 in. (238 × 165 × 91 mm) in size and weighs 5.5 lbs. (2.5 kg). It operates for about 2 h on a rechargeable Li-ion battery.

Additional compact imaging cameras include the FLIR 1020+28 IR thermal imaging camera and the CorDEX TP2410XP camera. Model 1020+28 features 1024 × 768 pixel imaging resolution and wide thermal range with better than 0.02°C thermal sensitivity. Readings appear on a 4.3-in. LCD with 800 × 480 pixel resolution. Model TP2410XP is one of CorDEX’s ToughPIX II explosion-proof digital cameras certified for safe operation in explosive and hazardous operating environments. It features an armored 2.7-in. LCD screen but weighs only 900 g.

These digital cameras show some of the imaging capabilities possible from lightweight, handheld units using various technologies. They provide at least 2 h operating time on rechargeable batteries to facilitate on-site measurements and imaging where needed, even under less-than-favorable conditions. For more information on these, please visit our website or contact a Transcat | Axiom Rental Account Manager for guidance at (760) 806-6600.