INFRATHERM
pyrometers IS 5 · IS 5-LO · IGA 5 · IGA 5-LO
41
6 Instrument
alignment
6.1 View
finder
The IS 5 and IGA 5 can be equipped with a view finder (through lens sighting) which is used for the align-
ment of the pyrometer to the measured object. The view finder is true-sided and parallax-free; a circle marks
the position of the measuring spot but not exactly the spot size. It is equipped with an adjustable eye-
protection filter to shade the ocular at very high temperatures.
Note:
For eye protection the ocular should be shaded above temperatures of 1500°C.
6.2
Laser targeting light
The laser targeting light is used for alignment of the pyrometer to a target. The laser spot marks the centre of
the measuring spot. As long as the laser targeting light is switched on, the temperature measurement of the
pyrometer is not operating. During this time the last measured temperature is held at the analog output.
The laser targeting light can be switched on and off either by pressing the button of the rear cover of the
housing, by using an external contact (see
4.1 connector pin assignment
) or via PC and software
InfraWin
.
If it is not switched off by one of the mentioned procedures, it will be switched off automatically after approx.
2 minutes.
Note:
The smallest diameter of the laser spot indicates the correctly focused measuring
distance. The diameter does not correspond to the spot size!
Attention:
Do not look directly into the laser beam!
Laser class 2 according to IEC 60825-1-3-4
Note:
The laser warning signs on the pyrometer should be easily viewable at all times,
even after it has been installed.
Note:
To prevent damage to the laser, the
targeting light
is switched off automatically
if the internal temperature of the pyrometer exceeds 50°C. It can only be used again
after the temperature fell below 50°C.
6.3 Video
module
The IS 5 and IGA 5 can be equipped with a built-in video module for alignment. This video module is a black-
and-white CMOS camera. The video signal can be transferred to a TV card or directly onto a monitor, so that
the measured object can be sighted using a target circle on the monitor. The target circle marks the place of
the measuring spot but not its exact size.
7
Optics / Optical heads
7.1
Spot sizes in relation to the measuring distance
The following table shows the pyrometer’s
spot size
M
[mm] in relation to the
measuring distance a
[mm]
(min. 90% of the radiation intensity)
. To get the specified values it’s necessary to choose the correct op-
tics/optical heads. Deviations from the focused measuring distance follows changing’s of the spot (see also
formula in section
Note:
The pyrometer can measure objects at any distance but the object has to be bigger or
at least as big as the spot size of the pyrometer in the measuring distance.
The focusing range for the optics (focused to measuring distance a [mm]) is set by factory, as shown in the
following table and should be taken into account when ordering (special focus distances upon request)!
