The power to do more - with non-contact infrared temperature sensors

Use an infrared sensor when physical contact with the target is undesirable, impractical or would influence the measurement. Typical examples include moving webs, rotating parts, delicate surfaces, electrically live components, small objects and high-speed production processes. IR measurement is particularly valuable when a contact probe cannot respond quickly enough or cannot maintain reliable contact.

Start with five parameters: target material, target temperature range, target size, distance between sensor and target, and required output signal. You should also consider ambient temperature, response time, mounting space and environmental conditions such as dust, moisture or oil.

The most important selection criteria are field of view, temperature range, output signal, emissivity, and ambient conditions. CleverIR offers powered ACE sensors, passive IRt/c sensors, AutoSmart solutions and adjustable sensors for more challenging targets. For unusual applications, CleverIR can help select and configure a sensor for the actual measurement conditions.

A powered sensor contains electronics and requires an external power supply. ACE, for example, operates from 12-30 VDC and can provide analog or digital outputs. The IRt/c is passive and self-powered, producing a thermocouple-compatible signal without requiring power at the sensor. This can be an advantage when power is scarce or relies on batteries. Self powered IRt/c’s are renowned for their robustness and longevity.

A passive IRt/c can be attractive when simplicity, reliability, small size and easy integration with existing thermocouple inputs are important, or when power supply is not easy to ensure (f.e. in remote areas where equipment relies on battery power). With no active electronics at the sensing point, it can also be useful in demanding industrial environments. The unpowered nature makes the IRt/c a non-energy storing, simple apparatus and thus suitable for ATEX applications.

ACE is particularly useful when you require a powered, configurable sensor with a standard analog or digital output, compact dimensions and a customized measurement range. It is available with different fields of view and can be configured for specific OEM applications.

AutoSmart is useful when the characteristics of an IRt/c sensing head are desirable but your control system requires an industrial analog signal such as 0-5 V, 0-10 V or 4-20 mA.

Often yes, but the application should be evaluated rather than treating the IR sensor as a direct mechanical replacement. Optical geometry, emissivity, target position, response time and controller input all need to be considered.

Yes. A properly selected IR sensor can continuously measure surface temperature and provide feedback to a PLC or controller. CleverIR applications include closed-loop thermal control in PCB processing and printing/drying equipment.

Yes. This is one of the main advantages of non-contact measurement. There is no mechanical connection to establish or maintain, making IR particularly suitable for conveyors, printing webs, rotating components and other moving targets.

Emissivity describes how effectively a surface emits infrared radiation compared with an ideal emitter. High-emissivity surfaces are generally easier to measure accurately than shiny, reflective low-emissivity surfaces, as these latter surfaces reflect IR radiation from other heat sources that interfere with the temperature measurement

Shiny metals have low emissivity and therefore emit relatively little infrared radiation of their own while reflecting radiation from surrounding objects. The sensor can consequently see a combination of target temperature and reflected environmental radiation.

Yes, but the measurement conditions matter. Adjustable LoE IRt/c models are specifically intended for low-emissivity targets such as metals and reflective surfaces, particularly at higher temperatures.

Potentially, but polished aluminium is a difficult IR target because of its very low emissivity. Target temperature, surface condition, viewing geometry and reflected surroundings should be evaluated before choosing a sensor.

It can. Emissivity may change with temperature as well as surface finish, oxidation, coatings, moisture and manufacturing processes. This is especially relevant when high absolute accuracy is required.

Often yes. Many paints and coatings have considerably higher emissivity than bare polished metal. The sensor then measures the coating surface, so you should ensure that its temperature represents the temperature you actually need to know.

Yes. Many plastics are good candidates for IR measurement, although optical properties vary with material, thickness, wavelength and temperature. Some very thin films may be transparent for IR radiation.

Yes. These are common applications because the material is often moving and cannot conveniently be contacted by a conventional temperature probe. CleverIR sensors are used in printing, drying and textile applications.

Not automatically. Standard glass does not transmit all infrared wavelengths in the same way it transmits visible light. Window material and sensor spectral response must be evaluated for the application. When you need a transparent window to measure through, select specific materials with desired transmission spectra in the infrared range.

These can absorb, scatter or emit infrared radiation and therefore introduce errors. The severity depends on concentration, wavelength, path length and process conditions.

Field of view describes the area observed by the sensor at a given distance. It determines the measurement spot size and therefore whether the sensor sees only the intended target or also its surroundings.

Approximately, it means that at a distance of 3 units the sensor observes a spot about one unit in diameter. Actual optical specifications should always be checked for the selected model.

Ideally, yes. If the target does not sufficiently fill the measurement area, background objects can influence the reading.

Usually yes. A shorter distance produces a smaller measurement spot and reduces the chance that surrounding surfaces enter the field of view. CleverIR's printing case similarly recommends mounting as close as practical where appropriate.

Choose optics that create a sufficiently small measurement spot and mount the sensor close enough to ensure that the component fills the field of view. Compact sensors such as the Micro IRt/c/AutoSmart M are intended for small targets and confined installations.

The sensor will also receive radiation from whatever is behind or around the target. The displayed temperature can therefore become a weighted measurement rather than the true target temperature. The IRt/c or ACE measurements are highly repeatable under repeatable environments, so corrections of measurement errors are often possible to yield reliable measurements.

The target must remain within the sensor's optical field under all expected mechanical tolerances and movement. Alignment becomes increasingly critical as the target gets smaller and the optics become narrower. Given the high repeatability of the IR sensors, any measurement errors can be (partially) cancelled out if environment conditions are reproducible.

Often yes, IR sensors can measure obliquely, but excessive angles can change the effective measurement area and increase sensitivity to reflections. The measured spot will be more elliptical the circular, and the best geometry depends on the target.

A side-view sensor can solve this problem. CleverIR offers side-view configurations intended for installations where the sensor needs to be mounted parallel to the target.

An IR sensor measures the radiation received across its field of view – and will average the temperature of all objects in its field of view. If several objects occupy that field, the output represents their combined contribution rather than separate temperatures. Separate measurements normally require separate sensors or controlled positioning.

Accuracy describes how close a measurement is to the true temperature. Repeatability describes how consistently the sensor produces the same result under the same conditions. For process control, excellent repeatability can be just as important as absolute accuracy.

Many processes are optimized around a stable temperature window. A repeatable sensor allows the machine to detect small process changes reliably, even when absolute temperature accuracy is not the only requirement.

CleverIR specifies ACE repeatability error at less than 0.1°C for the product family shown on its site.

Interchangeability indicates how closely one sensor matches another sensor of the same configuration. Good interchangeability is important for OEMs because replacement sensors should not require major machine recalibration.

Validate the sensor under actual operating conditions using a trusted reference method and representative targets. Do not validate only against an arbitrary handheld IR thermometer without considering emissivity, field of view and measurement geometry.

Yes, provided it has suitable accuracy and is used correctly. CleverIR offers the D501 family as precision handheld reference thermometers with NIST-traceable accuracy.

The two devices may not actually be measuring the same temperature. Contact probes are affected by thermal contact, heat sinking, mounting and response time, while IR sensors measure surface radiation.

Changing distance or angle may change the measurement spot, introduce background surfaces or alter reflected radiation. Check field of view and target geometry first.

The target may reflect radiation from that object into the sensor, particularly if the target has low emissivity.

Long-term stability depends on sensor technology and environmental conditions. Contaminated optics, mechanical changes and process changes can sometimes appear to be sensor drift, so these should be investigated before recalibration is assumed necessary.

Response time varies by model and configuration. IR sensing is particularly well suited to dynamic measurements because it does not require a probe to establish thermal equilibrium through physical contact.

Yes. CleverIR uses IR measurement in high-throughput applications including printing and PCB testing where rapid feedback is required.

Yes. If heating, drying or curing is the process bottleneck, real-time surface-temperature feedback can allow the machine to operate closer to the optimum process window instead of relying on conservative fixed settings.

Yes. Monitoring substrate temperature can help identify drying behavior and enable better control of heater power, airflow and line speed.

Temperature behavior can provide useful information about evaporation and drying. CleverIR describes how surface temperature changes as moisture evaporates and the substrate reaches its dry-out point.

Yes. CleverIR has applied sensors after UV curing stages to monitor substrate temperature and support process optimization.

Yes, provided the fixture geometry, response time and target size are suitable. CleverIR documents a PCB fixture application where non-contact measurement enabled fast individual-board testing.

Yes. Detecting thermal deviations before they create defects can reduce overprocessing, underprocessing and inconsistent product quality.

Potentially. Closed-loop temperature information can help avoid unnecessary heating and allow a process to operate closer to its actual thermal requirement.

It can provide valuable temperature information, but whether it can form part of a safety function depends on the complete safety architecture, required safety integrity and applicable regulations. A standard process sensor should not automatically be assumed to be a certified safety device.

Depending on the product family, options include J- or K-type thermocouple-compatible signals, 0-5 V, 0-10 V, 4-20 mA and digital UART/RS232 options.

Yes, a correctly selected IRt/c is designed to generate a thermocouple-compatible output for connection to an appropriate J- or K-type input.

Usually yes if the PLC has an input compatible with the selected ACE output. Available configurations include standard voltage/current outputs and digital communication options.

For longer cable runs and electrically noisy industrial environments, 4-20 mA is often attractive. For short machine-level connections, 0-10 V may be simple and convenient. The best choice depends on the control architecture.

Yes. CleverIR offers configurations with 0-5 V outputs where appropriate.

Yes. ACE is available with digital UART/RS232 functionality in addition to analog configurations.

Yes. UART is a straightforward digital interface that can be converted by suitable interface electronics or gateways to the protocol required by the host system.

Yes. CleverIR's powered solutions can be configured/scaled for the intended measurement range within their supported limits.

Filtering should match the thermal dynamics of the process. Too much filtering can hide fast temperature changes; too little can make control unnecessarily sensitive to noise. Start from the required process response rather than choosing an arbitrary filter constant.

Yes, provided the PLC has sufficient compatible input channels or suitable I/O expansion. Multiple sensors are often used when different process zones need independent temperature feedback.

It depends on the model. CleverIR offers sensors for different ambient-temperature ranges, including models with air purge/cooling for demanding environments.

Use a suitable cooling arrangement or select a sensor designed for the higher ambient temperature. Do not assume that a high target-temperature capability means the sensor body can tolerate the same temperature.

An air purge directs clean air around the sensor optics and/or housing to help keep the optical path clean and, in some configurations, provide cooling.

Consider it when dust, oil, moisture, fibers, ink mist or other contaminants could settle on the optics, or when cooling is required. CleverIR offers air-purge solutions for ACE and Micro IRt/c configurations.

Even partial contamination can alter the radiation reaching the detector and introduce measurement error. CleverIR notes that lens contamination is a significant issue in industrial environments.

Use the cleaning method recommended for the specific sensor and optical material. CleverIR's application guidance recommends keeping the optics clean and, in relevant applications, using suitable cleaning materials such as isopropyl alcohol carefully.

Yes, but grounding, shielding, cable routing and signal selection matter. Some IRt/c models use stainless-steel housings and shielded cables specifically suited to industrial environments.

Vibration can matter if it changes the sensor's alignment or causes the target to move in and out of the measurement spot. Mechanical mounting should therefore be sufficiently rigid.

Yes. Condensation changes infrared transmission and can produce incorrect readings. Preventing condensation or keeping the optical path clean is important.

Yes. Compact and side-view models are specifically useful where installation space is limited.

Yes. This is particularly useful for moving PCBs, automated test fixtures and processes where a contact probe would interfere with throughput.

Yes, provided the optical spot is smaller than or appropriately matched to the component and the surface properties are understood.

Yes. Board temperature can influence viscosity, flow and curing behavior. CleverIR documents closed-loop PCB temperature control in dispensing equipment.

Yes. Non-contact measurement is well suited to leaf-temperature monitoring and has been used in agricultural research and greenhouse optimization.

Leaf temperature contains information about plant energy balance and transpiration. It can therefore complement air-temperature, humidity, light and CO₂ measurements when optimizing growing conditions.

In some applications, yes, using an appropriate measurement arrangement. CleverIR offers solutions and has documented non-invasive fluid-temperature applications; the specific geometry and materials must be assessed.

Yes. CleverIR's portfolio has been used in medical OEM applications, including fluid-related temperature measurement and cooling systems. The complete medical device must of course satisfy its applicable validation and regulatory requirements.

Yes. CleverIR documents infrared temperature measurement during UV curing in infrastructure rehabilitation equipment.

Yes. Temperature feedback after heating or curing stages can help establish a repeatable process window and permit higher line speeds while maintaining print quality.

Yes. Their non-contact operation, small dimensions and fast response make them suitable for many robotic and automated-machine applications.

Check lens contamination, target emissivity, field of view, measurement distance, alignment and whether a colder background is entering the measurement spot.

Check for reflected radiation from heaters or other hot objects, incorrect emissivity assumptions, hot background surfaces and electrical scaling errors.

Possible causes include target movement, changing reflections, an undersized target, electrical noise, rapidly changing surface conditions or an unstable mounting arrangement.

Opening the machine can change ambient temperature and reflected infrared radiation. Low-emissivity targets are particularly sensitive to changes in their thermal surroundings.

Color in the visible spectrum is not necessarily the same as emissivity in the infrared spectrum. Surface composition, coating, gloss and texture can all matter.

Check sensor temperature, lens contamination, mounting movement, changing process conditions and reflected heat sources before assuming electronic drift.

Verify the output type, wiring, PLC input configuration, scaling, temperature range and grounding. For thermocouple outputs, also verify the correct thermocouple type and input configuration.

Yes. Long runs next to motors, drives and power cables can introduce electrical interference, particularly with low-level signals. Follow good industrial wiring practices.

Test the sensor against a stable, known target under controlled geometry and compare it with a suitable reference. If performance is stable there, investigate target emissivity, optics, mounting and process conditions.

Not automatically. First eliminate contamination, geometry changes, electrical scaling problems, reflected radiation and actual changes in the process.

Yes. Customization is an important part of CleverIR's OEM offering, particularly with flexible platforms such as ACE and AutoSmart.

Yes, depending on the sensor platform. ACE can be configured for application-specific ranges within its supported 0-250°C operating range.

Yes. Target dimensions, mounting distance and surrounding surfaces can be evaluated to determine suitable optics.

Yes. CleverIR states that test samples are available at reduced prices so customers can evaluate the technology in their application.

Provide target material, target temperature range, target dimensions, sensor-to-target distance, ambient temperature, desired output, response-time requirement, environmental conditions, available mounting space and expected quantities.

Yes. CleverIR operates internationally, with headquarters in the Netherlands and a U.S. facility in Watertown, Massachusetts, and works with distributors worldwide.

According to CleverIR, its product manufacturing is located in the United States for relevant Exergen products and in Europe for ACE and AutoSmart.

Yes. CleverIR positions its offering around OEM application support rather than only supplying a component. This can include sensor selection, configuration and integration advice; its Plant Lighting case, for example, describes support with sensor selection/programming, mounting and data analysis.

Send the sensor model and configuration, target material and temperature, mounting distance and angle, target size, ambient conditions, output/interface details, photographs or drawings of the installation, measured values and the reference values you expected. This usually allows the application to be assessed much faster.

Define the measurement problem rather than selecting a sensor first. Describe what you need to measure, why the temperature matters to the process, target material and size, expected temperature range, available mounting geometry, environment and control-system interface. CleverIR can then help determine whether a standard sensor, configured solution or custom approach is most appropriate.