Measuring - VOLTCRAFT IRS-350 Notice D'emploi

If the temperature is increased, the heating process is indicated by function display OUT (1).
If the temperature is decreased, function display OUT goes out or starts flashing. If the actual tempera-
ture (display 3) is above the setpoint temperature by more than 4°C (display 2), both red function dis-
plays ALM1 and ALM2 are activated. The displays indicate a significant difference in temperature. If the
difference is less than 4°C, the displays go out.
ALM1: the heating process stops temporarily
ALM2: the cooling process is intensified.
There is only little difference between the actual and
the setpoint temperature of the physically generated
temperature (heating element). The graph shows the
difference between reference temperature and actual
temperature.
External factors like draught can increase this differ-
ence.

Measuring

To avoid faulty measurements, the distance between the measuring area and the infrared thermometer
must be taken into account. The optical measuring ratio is stated for every IR measuring instrument. This
ratio states at what distance the measuring cone has a certain diameter.
If the measured area is smaller then the measuring cone of the IR thermometer, false values will be dis-
played.
Example:
An optical measuring ratio of 10:1 measures an area of 1 cm at a distance of 10 cm. If the distance is
increased to 100 cm, an area of 10 cm is needed to measure correctly. The bigger the ratio the more pre-
cise the results, because only a small area is needed to carry out the measurement. The measuring dis-
tance can be increased which will render the same results as a small measuring ratio.
Due to mechanical inaccuracies of IR optics and due to the fact
that infrared heat rays are invisible to the human eye, a tolerance
range has to be kept to the colder areas when measuring. There-
fore, the radius of the measuring area must be at least 1 cm bigger
than the radius of the calculated IR measuring cone.
In addition, a distance has to be kept between the thermal source
and the IR thermometer to avoid any direct thermal influence on
the measuring optics. Please also observe the operating instruc-
tions of your IR thermometer.
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