FAQ's

 
1. What are some typical applications for the Testo Thermal Imagers?
2. What are some advantages of the Testo Thermal Imagers
3. How many images can the SD card store, and can I design my own reports with the Testo software?
4. Can I adjust emissivity setting? What is the impact on the temperatures displayed if the emissivity setting is wrong?
5. Can thermal imagers see through windows or walls?
6. Does the color of the object I am measuring impact the reading I see?
7. Does a thermal imager work in complete darkness?
8. What is the most important aspect of capturing a good thermal image?
9. What image features can I change in the image processing software?
10. What are factors that might distort the temperature readings shown on the imager?
 
  What are some typical applications for the Testo Thermal Imagers?  
 

Building thermography - Both the testo 875 and 881 will find areas with missing insulation, hidden wet areas caused by leaks, areas where hot or cold air is leaking through the building envelope, and can scan HVAC systems for machinery or duct sealing problems.
Industrial plant applications - These imagers can be used for regular electrical switchgear surveys, to find overheating bearings in rotating equipment, to verify steam trap operation, and to check heat exchangers for blocked passages. They can be used in most any application where heat flow is an indicator of proper operation of systems or equipment, at temperatures up to 660ºF. An optional high temperature lens will measure to 1020ºF.

 
 
  What are some advantages of the Testo Thermal Imagers  
 

Testo Thermal Imagers are easy to operate and can detect even minute temperature differences in target objects. They have an ergonomic design and light weight that is ideal for extended use. They have a field replaceable Li-Ion battery which provides 5 hours of operation on a single charge. An integrated digital camera and the "IRSoft image processing" software makes analysis and report generation a breeze. Optional telephoto and protective lenses are features offered only by Testo in this class and price range.

 
 
  How many images can the SD card store, and can I design my own reports with the Testo software?  
 

Up to 1000 images. A 1GB SD card is provided with every imager. The stored images can be accessed using the provided IRSoft software for report writing using predefined or user customized report templates.

 
 
  Can I adjust emissivity setting? What is the impact on the temperatures displayed if the emissivity setting is wrong?  
 

Can I adjust emissivity setting? The testo 875 and 881have seven predefined material emissivities programmed into the instrument, as well as a user defined emissivity setting, that are available at the touch of the joystick. For target temperatures above ambient, an emissivity setting that is too high will indicate a temperature that is higher than actual. The reflected temperature correction (or RTC) can also be adjusted by the user to provide the most accurate temperature reading possible. Emissivity values for other common materials can be obtained from the instruction manual.

 
 
  Can thermal imagers see through windows or walls?  
 

No. While glass allows visible light to pass through, it is opaque to infrared wavelengths. Thermal imagers contain a ‘longwave’ infrared detector, and measure the surface temperature of target objects. Elements of a wall become visible in a thermal image when there is a temperature difference (~20ºF) on opposite sides of the wall.

 
 
  Does the color of the object I am measuring impact the reading I see?  
 

No. A dark colored object in the sun will absorb more energy than a light colored one, but the emitted IR radiation depends on the object temperature and is not affected by the color. A heater painted half black and half white would register the same temperature.

 
 
  Does a thermal imager work in complete darkness?  
 

Yes. Thermal imagers operate in a range of the spectrum outside the visible light wavelengths and is unaffected by light (except as it is a source of heat).

 
 
  What is the most important aspect of capturing a good thermal image?  
 

Focus is the most critical element in recording a thermal image. Focus and the perspective of the target area are the image characteristics that cannot be changed.

 
 
  What image features can I change in the image processing software?  
 

Key features for image interpretation, such as span and level, or for image presentation, such as palette selection, can all be modified in the software.

 
 
  What are factors that might distort the temperature readings shown on the imager?  
 

The most common sources of error in temperature measurement with a thermal imager are:
- unfocused image
- incorrect emissivity or RTC (Reflected Temperature Correction) settings (the error introduced is small until the differences from actual to setting values are large).
- thermal reflection
- move the position of the imager to determine if you are observing reflected temperatures. Reflections will move as you do.

 
 
 
 
 

 

The thermal imager testo 870 was specially developed for your applications, in cooperation with heating constructors, building contractors, service engineers and facility management specialists – for example for detecting leakages, localizing cold bridges or visualizing overheated connections.