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7
OPERATlON & APPLICATION
7.1
Calibration by comparison
To verify or calibrate a temperature sensor by comparison with an internal or external Pt100 standard follow the
procedure indicated below. For correct operations strictly follow the following recommendations:
•
Measure the outside diameter of the sensor to be tested.
•
Insert the sensor to be tested in one hole of the thermal equalizing block. For a correct calibration the outside
diameter of the sensor under test should be approximately 0.5 mm less than the inside diameter of the hole;
•
If required use the appropriate well adapter (see the figure below).
•
Do not force the sensor to be tested into the thermal equalizing block (see the figure below).
NO
OK
NO
OK
>0.5 mm
ATTENTION
D
O NOT INSERT THE SENSOR UNDER TEST IN THE THERMAL EQUALIZING BLOCK WHEN THE OVEN IS AT A HIGH TEMPERATURE
.
T
HERMAL SHOCK COULD DAMAGE THE SENSING ELEMENT OF THE PROBE
.
A
T THE END OF THE TEST DO NOT REMOVE IMMEDIATELY THE PROBE
/
S FROM THE THERMAL EQUALIZING BLOCK
.
W
AIT FIRST FOR THE TEMPERATURE CALIBRATOR TO COOL
.
A
T THE END OF THE OPERATION
:
WAIT FOR THE THERMAL EQUALIZING BLOCK TO BE COMPLETELY COOLED BEFORE PLACING THE
CALIBRATOR INTO THE CARRYING CASE
.
7.1.1
Calibration using the internal Pt100 sensor
•
Start the calibration only at ambient temperature.
•
Insert the sensor under test in the correct hole with the sensing element into the recommended calibration zone as
indicated in the following figure.
•
Switch the instrument on using the main switch on the rear panel.
•
Pressing the
<
▲
>
key the set-point values will increase.
•
Pressing the
<
▼
>
key the set-point values will decrease.
•
To confirm values, press the
<E>
key until a sound is made by unit.
•
Verify the reading temperature on the display with the values reported on the Certificate of Conformity and make the
relative modifications.
•
Calibrate the value read on the sensor under test with the correct value on the indicator. The check can be
accomplished with several temperature values. In order to follow this procedure just set up the set-point to the
relevant temperature value and wait for stabilization.
13