Distance and Spot Size
Ensure the sensor is positioned
so that it can only detect infrared
radiation from the target.
The size of the area (spot size) to
be measured determines the
distance between the sensor and
the target. The spot size must
not be larger than the target. The
sensor should be mounted so
that the measured spot size is
smaller than the target.
We normally recommend the
target is at least twice the size of
the given measured spot for
maximum accuracy.
PREPARATION
Ambient Temperature
The sensing head is designed to operate in ambient temperatures from 0°C to 180°C.
The main enclosure is designed to operate in ambient temperatures from 0°C to 70°C.
Avoid thermal shock. Allow 20 minutes for the unit to adjust to large changes in ambient
temperature.
Atmospheric Quality
Smoke, fumes or dust can contaminate the lens and cause errors in temperature
measurement. In these types of environment the air purge collar should be used to help keep
the lens clean.
Electrical Interference
To minimise electromagnetic interference or ‘noise’, the sensor should be mounted away from
motors, generators and such like.
Wiring
Check the distance between the sensor and the indicating/controlling device. If necessary, the
sensor can be ordered with a longer cable attached. Contact Calex for information about
extending the cable.
Power Supply
A suitable intrinsically safe isolator must be used. See
Specifications
for the supply voltage,
current and safety requirements.
MECHANICAL INSTALLATION
Mounting
The sensing head is supplied with 2 mounting nuts. The sensor can be mounted on brackets
or cut outs of your own design, or you can use the fixed and adjustable mounting bracket
accessories, which are shown in the following diagram.
Sensor
CORRECT
Target larger
than spot size
Target smaller
than spot size
INCORRECT
Background
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