testo 830-T4 Manual De Instrucciones página 15

Do not measure with clouded lens.
Keep measurement field (area between instrument and
object being measured) free of interferences: no dust and dirt
particles, no moisture (rain, steam) or gases.
Infrared measurement is a surface measurement
testo 830-T4
If there is dirt, dust, frost etc. on the surface, only the top layer will
be measured, i.e. the dirt.
Ø 16 mm
In the case of shrinkwrapped foodstuffs, do not measure in air
pockets.
If values are critical, always subsequently measure using a
contact thermometer. Particularly in the food sector, the core
temperature should be measured with a penetration/immersion
thermometer.
Adaptation time
If the ambient temperature changes (change of location, e.g.
inside/outside measurement) the instrument needs an adaptation
time of 15 minutes for infrared measurement.
11.2 Emissivity
Materials have different emissivities, i.e. they emit different levels
of electromagnetic radiation. The emissivity of testo 830 is set in
the factory to 0.95. This is the ideal value for measuring non-
metals (paper, ceramics, plaster, wood, paints and varnishes),
plastics and food.
Bright metals and metal oxides are only suited to a limited
extent to infrared measurement on account of their low or
nonuniform emissivity.
Apply emissivity enhancing layers such as varnish or emission
adhesive tape (Item no. 0554 0051) to the object being
measured. If this is not possible, measure with the contact
thermometer.
Emissivity table of the most important materials
(typical values)
Ø 36 mm
Ø 24 mm
Ø 18 mm
500 mm
700 mm
1000 mm
1500 mm
Ø 68 mm
Laser
Laser
2000 mm
15
Ø 100 mm