Basics
4.2 Emissivity of Target Object
To determine the emissivity of the target object refer to section 12.1 Determination of Emissivity on page 81. If emissivity is low, measured results could be falsified by interfering infrared radiation from background objects (such as heating systems, flames, fireclay bricks, etc. close beside or behind the target object). This type of problem can occur when measuring reflective surfaces and very thin materials such as plastic films and glass.
This measurement error can be reduced to a minimum if particular care is taken during installation, and the sensing head is shielded from these reflecting radiation sources.
4.3 Ambient Temperature
The sensing head was developed for the following ambient temperature ranges:
•MIH: 0 to 180°C (32 to 356°F)
•MIC: 0 to 125°C (32 to 257°F)
•MID: 0 to 85°C (32 to 185°F)
The MID can operate in ambient temperatures up to 200°C (392°F) with the air‐cooling accessory.
4.4 Atmospheric Quality
If the lens gets dirty, infrared energy will be blocked and the instrument will not measure accurately. It is good practice to always keep the lens clean. The Air Purge Jacket helps keep contaminants from building up on the lens. If you use air purging, make sure a filtered air supply with clean dry air at the correct air pressure is installed before proceeding with the sensor installation.
12 | MI |