Relevant Technical Issues and Precautions for Infrared Thermometers
Why Use an Infrared Thermometer?
Infrared thermometers adopt infrared technology to quickly and conveniently measure the surface temperature of objects. Temperature readings can be obtained rapidly without making mechanical contact with the measured object. Simply aim at the target, pull the trigger, and read temperature data on the LCD display.
Infrared thermometers are lightweight, compact and easy to operate. They can reliably measure hot, hazardous or hard-to-reach objects without contaminating or damaging the measured targets.
An infrared thermometer can take multiple readings per second, while contact thermometers require several minutes for a single measurement.
How Does an Infrared Thermometer Work?
The infrared thermometer detects invisible infrared energy emitted by various objects. Infrared radiation is part of the electromagnetic spectrum, which includes radio waves, microwaves, visible light, ultraviolet rays, gamma rays and X‑rays. Infrared lies between visible light and radio waves. Infrared wavelength is commonly measured in micrometers, with a wavelength range of 0.7 μm to 1000 μm. In practice, the waveband of 0.7 μm to 14 μm is applied for infrared thermometers.
How to Measure Temperature with an Infrared Thermometer?
To perform temperature measurement, aim the infrared thermometer at the object to be measured, pull the trigger and read temperature data on the instrument's LCD. Ensure the proper distance-to-spot ratio and field of view. Several important points must be kept in mind when using an infrared thermometer:
① It only measures surface temperature; the infrared thermometer cannot measure internal temperature.
② Temperature measurement cannot be taken through glass. Glass has special reflection and transmission characteristics and will prevent accurate infrared temperature readings. However, measurement can be carried out through an infrared window. Infrared thermometers are not recommended for measuring bright or polished metal surfaces (stainless steel, aluminum, etc.).
③ Locating hot spots: To find hot spots, aim the instrument at the target and scan up and down over the target until the hot spot is identified.
④ Pay attention to ambient conditions: steam, dust, smoke, etc. These substances will block the instrument's optical system and affect accurate temperature measurement.
⑤ Ambient temperature: If the infrared thermometer is suddenly exposed to an ambient temperature difference of 20℃ or more, allow the instrument 20 minutes to acclimatize to the new ambient temperature.
