Ways To Determine Emissivity - IFM Electronic EFECTOR 600 TW2000 Operating Instructions Manual

Overtemperature
Incorrect connection of sup-
ply voltage
Supply voltage
≤ approx. 16 V
Temperature below lower
threshold
Temperature above upper
threshold

13 Ways to determine emissivity

Technical literature or operating manuals often contain data on the emissivity of
various materials� This information should be used with caution, however� It is
important to know for which temperature and which wavelength the emissivity
value is applicable� Furthermore, the stated emissivity values were obtained under
ideal conditions� In actual practice, the total emissivity of the target object will vary,
depending on the amount of extraneous radiation transmitted through the object
from the background or reflected onto the object from the foreground�
The emissivity can be determined using one of the following methods:
Contact measurements
Measure the temperature with a contact thermocouple and measure the surface
temperature with a pyrometer� Adjust the emissivity coefficient on the pyrometer
until both devices show the same temperature� When measuring with the thermo-
couple, make sure to have good thermal contact and low heat dissipation�
22
Display ot alternately shows overtempera-
ture and measurement reading at = 0.5 Hz.
The corresponding LED flashes at 4 Hz when
the output is switched off�
Switching output LED flashes at 2 Hz.
LED, display, switching output and analogue
output are deactivated.(When voltage ≥ 16
V the device switches on and the switching
outputs are activated)�
The display shows UL�
The display shows 0L�