Working With Alarms; Setting The Reference Temperature - FLIR ThermaCAM B2 User Manual

8.4

Working with alarms

You can choose between the following alarm outputs:
a color alarm, which will assign a color to all pixels above or below a preset tem-
■
perature level
a silent alarm, which, compared to the color alarm, will make the font of the temper-
■
ature result increase in size and its background turn red
an audible alarm, which, compared to the visual alarm, also triggers a 'beep'.
■
A settings can also be made in the camera so that an alarm output takes into account
the reference temperature. A typical application when you would want to use an alarm
that takes into account the reference temperature is screening of people for face
temperature detection.
Firstly, the reference temperature is set by screening 10 persons with normal face
temperature. The camera puts each of these 10 results in an internal camera buffer
and calculates the average temperature value after having discarded the two highest
and two lowest values in the event of erroneous samples. Every time a new sample
is saved to the internal buffer, the oldest sample will be discarded and a new reference
temperature will be calculated 'on the fly'.
Using an alarm that takes into account the reference temperature means that an alarm
output will only be triggered if the temperature value exceeds the sum of the average
temperature value in the buffer + the user-defined delta alarm offset value.
8.4.1

Setting the reference temperature

Step Action
1 Press YES to display the vertical menu bar.
2 Point to Settings on the Setup menu and press YES.
3 In the Settings dialog box, press the navigation pad up/down to go to Trigger
button.
4 Press the navigation pad left/right to select Update ref temp.
5 Press the navigation pad up/down to go to Shutter period.
6 Press the navigation pad left/right to select shutter period.
Although the shutter period works independently of other functions described in
this document, FLIR Systems recommends that Short is selected when using the
camera for detection of face temperature.
➲ Selecting Normal will calibrate the camera at least every 15th minute, while se-
lecting Short will calibrate the camera at least every 3rd minute.
Publ. No. 1557882 Rev. a156 – ENGLISH (EN) – February 28, 2006
8 – Tutorials
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