IDEAL 61-847, Руководство пользователя

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Auto Power Off
In the HOLD mode, if there is no operation for 15 seconds, the thermometer
will automatically power off and save the currently held measurement.
NOTE : During measurement, it is best to ensure that the measured target
diameter is twice the spot size (S) of the thermometer, and then determine the
test distance (D) according to the D:S diagram (refer to D:S part).
For example, if you use the 61-847 to measure the temperature of an object
with a diameter of about 4” (10cm), then according to the above, the spot
size (S) of the thermometer should be about 2” (5cm) for highest accuracy,
and according to the D:S diagram, the measured distance (D) is about 24”
(60 cm).
Emissivity
Emissivity is the term used to describe the efficiency with which a particular
surface emits Infra-Red Radiation IN THE WAVELENGTHS that are detectable
by the sensor in the IR Thermometer. Its sensitivity is in the 8 to 14-micron
wavelength range. To be sure, a hot mass will radiate IR in many different
wavelengths, but the sensing technology employed in this type of instrument
has a narrow bandwidth. Some materials, such as electrical tape, human
skin, certain types of paints are efficient emitters in these Wavelengths.
Others such as aluminum, brass, and gold are inefficient emitters, again, IN
THESE WAVELENGTHS. Heat a bar of gold to 200 degrees and try to read
its temperature and it will appear cold. Cover it in electrical tape, and scan
the tape, and the temperature will be much higher and much more accurate.
Please remember this when making measurements of certain objects. This can
and does greatly affect the accuracy of the readings. This is why you can set
the emissivity value in the meter.
Human Skin 0.98
Smooth Ice 0.96
Carbon Candle Soot 0.95
Oil Based Paint 0.94
White Bond Paper 0.93
Snow 0.85
Stainless Steel 0.85
Oxidized Copper 0.78
Rust 0.71
Cast Iron 0.64
Buffed Stainless Steel 0.16
Polished Brass 0.03