What are Industrial IR Thermometers?

Also, referred to as laser thermometers, an industrial IR (infrared) thermometer is a tool that helps make accurate infrared measurements inside a manufacturing plant, laboratory, office, etc. without coming in physical contact with the target object. A sub-type of thermal radiation thermometer, an IR thermometer can measure a range of surface types.

Design and Benefits

Generally, the IR thermometer (since it’s a non-contact device) would be equipped with a circle laser that lets you focus more accurately on the target area. Most importantly, there’s a lens that focuses or transports the IR radiation to a detector. The detector converts the radiant energy into an electrical signal, which could be displayed in temperature units after having made compensations for ambient temperature. This is what makes temperature measurement from a distance or sans contact possible. There is also a non-contact thermometer that helps measure temperature in scenarios where probe-type sensors such as thermocouples are not usable or can’t produce accurate information for various reasons.

An IR thermometer is ideal for spot measurements. It comes in different configurations, which makes it relevant in a range of industries. For instance, there are IR thermometers specially designed for small, cramped spaces and high surrounding temperatures. The thermometer also has a backlit display that could be toggled off or on to read surface temperatures in badly-lit areas. Some thermometers’ emissivity setting could be adjusted. This means it could be custom-set to measure temperatures of non-reflective and reflective surfaces.

Usage Scenarios

An IR thermometer helps measure a moving object’s temperature; if electromagnetic field is surrounding the object; the object is in a controlled atmosphere such as a vacuum; in scenarios where a quick response is needed; or physical contact would mar the object or thermometer sensor.

An infrared thermometer can be used for serving a range of temperature supervision functions. Examples include cloud detection for distant telescope operation, testing electrical or mechanical equipment for hot spots and temperature, measuring a patient’s body temperature without touching the individual, checking oven or heater temperature, testing for fire-fighting hotspots, monitoring components or constituents in processes that involve cooling or heating, and measuring volcano temperature. During an epidemic (such as ebola or SARS) breakout, IR thermometers also help examine landing travellers for fever.

Limitations

The IR thermometer can only measure exposed surfaces’ temperature; it cannot penetrate glass or other similar transparent barriers. Some IR thermometers come with a prearranged emissivity value, which cannot be changed. Most IR thermometers, however, let the user select emissivity value based on the material being measured: paper, metallic or wood surfaces. In case a user measures glossy metallic surfaces – for instance, cylinders – the non-contact tools could only be used for ascertaining temperature tendencies as it won’t be possible to compute absolute temperature with an IR thermometer on shiny or polished surfaces. If the thermometer available is non-adjustable in nature, then a non-reflective tape or paint would have to be applied to the surface (if it’s reflective) for measuring temperature. This hack, however, would most likely cause some accuracy loss.

When measuring surface temperature, there should be some space between the thermometer and target object. At times, inaccurate readings are likely when a hotter body in the vicinity reflects the radiation. For instance, the body temperature of the individual holding the device could come into play.

Making Adjustments

A sensor that has an alterable emissivity setting could also be incorporated to calibrate a given surface’s sensor, or for measuring a surface’s emissivity. When a surface’s temperature is accurately known (with the help of a contact thermometer), the emissivity setting of the sensor could be altered until the IR technique temperature measurement matches the temperature arrived at via the contact method. The emissivity setting would denote the surface’s emissivity, which could be considered for future measurements.