Infrared Thermometers FAQs
I am with a blood bank and my IR thermometer shows the outside of my blood bag about 2°C higher than temperature I get with my probe type thermometer measuring the blood inside. What is causing this?
The thermometer only measures the temperature of the surface of the bag. This is OK if the bag is in the cold environment because the outside of the bag will be the same as the inside. But after a few minutes at room temperature the outside of the bag gets warmer – even though the blood inside is still cold. Mixing the blood in the bag before taking a reading will cool the outside some. The only way to prevent this is to cover the outside of the bag to insulate it from the warmer air. Then the IR temperature should be the same as the inside temperature.
Can I use the IR Thermometer to measure a screen or wire mesh?
The readings may not be accurate as the IR thermometer will be reading through the holes in the screen also. The larger the size of the mesh – the larger the error.
Can I use the IR Thermometer to measure a 2” diameter pipe?
The accuracy of the readings will be affected by the field of view. If the field of view for the IR thermometer is greater than the diameter of the pipe at that particular distance then the readings may not be accurate because the thermometer will be reading surfaces behind the pipe as well as the pipe. If you move the IR closer to the pipe until the diameter of the pipe if greater than the FOV then you will get accurate readings.
Why doesn’t the IR thermometer show the same room temperature readings as my wall thermostat?
The wall thermostat is showing the temperature where the sensor is located. If you can locate the sensor measure as close as possible to it. The IR Thermometer is measuring the surface temperature of the object you are pointing it at which may not be the same as the air temperature. If the air temperature changes objects with large masses will be slower to change. For example if the air temperature went from 32°F to 80°F after the sun came up, a rock would stay much colder than the air temperature.
Does DeltaTrak have an Infrared Thermometer that stores readings (logs data)?
Yes. The 15006 IR Thermometer can store up to 99 temperature readings.
What DeltaTrak handheld IR Thermometer has the best accuracy?
The 15006 has the best accuracy with a spec of ±1°C (1.8°F) from 0°C to 100°C (32°F to 212°F))
What DeltaTrak IR Thermometer would you use for production lines?
The 15021-15024 On-Line IR Thermometers. These models come with LCD displays and either milliamp or millivolt outputs to connect to external meters. They also come with 2 different Field of View options. One has a 33:1 ratio at all distances and the other has a crossing field of view that allows it to be only 6 mm at 200 mm. This allows it to measure a smaller diameter at that distance than any of the other models. All require an external power source.
Can I get my older 15005 IR Thermometer calibrated?
The 15005 was discontinued many years ago and the equipment to calibrate this model is no longer available. You can test the calibration using crushed ice and water. The calibration can only be verified by DeltaTrak and a Certificate of Calibration issued only if it is still in calibration specifications. If it is outside of calibration specifications after you perform the crushed ice and water test you need to purchase a newer unit such as the 15006.
What IR Thermometer is a suitable replacement for the discontinued 15005?
The model 15006 is the closest suitable replacement in specifications and operation.
What IR Thermometer is a suitable replacement for the 15002, 15003, 15030, 15031, 15028, 15029?
The 15036 is the closest suitable replacement in specifications and operation.
Can I get my 15002 or 15002 calibrated?
The 15002 and 15003 can be calibrated and certified for the normal fee. They require a 2 point calibration at 25°C and 363°C. These points are required to make the thermometer accurate throughout its range.
What does “Field of View” mean and how does it affect my readings.
“Field of View” is the area of a surface being measured by an IR Thermometer as a given distance. For example an IR with a field of View of 15:1 will read a 1” diameter area at a distance of 15”. A 30:1 IR would read a 1” diameter area at 30”. This ratio is proportional at greater distances also.
This affects your reading if you are trying to measure an object smaller than your Field of View – the IR Thermometer will read temperatures behind the object also and get false or inaccurate readings.
What can I do if my 15036 or 15006 IR Thermometer is not reading accurately?
Try the following advice
- Check to see if the scale is correct - °C or °F.
- Make sure the temperature scale setting on the unit is set correctly.
Check the emissivity setting (if applicable) Dark (.95) for most applications Bright (.70) for reflective metals. - Make sure the diameter of the area you are measuring is smaller than the “Field of View” area for the model of thermometer and distance from the measured area.
- Allow 20 minutes for the internal thermometer temperature to stabilize to prevent thermal shock.
- Use crushed ice and water to verify the calibration accuracy.
What Is Thermal Shock and how does it affect my readings?
An IR Thermometer goes into thermal shock when readings are taken at the same time the thermometer is changing temperature internally. i.e. If you take an IR Thermometer from a 25°C room into a 0°C cooler, the thermometer will take accurate readings for about 10 seconds then go into thermal shock. When this happens the temperature readings will go lower and be less accurate until the IR Thermometer internal temperature stabilizes at the 0°C. The best way to prevent thermal shock is to take the reading immediately or allow at least 20 min for the unit to stabilize before taking a reading. Some models are more affected by this and protective covers can be purchased for some model to reduce this effect.
What is Emissivity and how does it affect my IR Thermometer readings?
Emissivity is a measurement of the amount of infrared light that is reflected and passes through an object. IR light passing through an object and reflected by an object creates inaccurate temperature readings as they do not reflect the actual temperature. The greatest reflectors of IR are shiny metallic surfaces like stainless steel and aluminum. These have an Emissivity rating of Bright (.70). Flat black objects reflect the least amount of IR so get the most accurate readings with an Emissivity setting of Dark (.95). Some IR Thermometers have adjustable Emissivity for greater accuracy with different materials.
What does “Field of View” mean and how does it affect my readings.
“Field of View” is the area of a surface being measured by an IR Thermometer as a given distance. For example an IR with a field of View of 15:1 will read a 1” diameter area at a distance of 15”. A 30:1 IR would read a 1” diameter area at 30”. This ratio is proportional at greater distances also.
This affects your reading if you are trying to measure an object smaller than your Field of View – the IR Thermometer will read temperatures behind the object also and get false or inaccurate readings.