Loading ...
Loading ...
Loading ...
9 Test Probe Calibration
For optimum accuracy and stability, allow the calibrator to warm up for 10
minutes after power-up and then allow adequate stabilization time after reach
-
ing the set-point temperature. After completing operation of the calibrator, al
-
low the well to cool by setting the temperature to 25°C for one-half hour before
switching the power off.
9.1 Calibrating a Single Probe
Insert the probe to be calibrated into the well of the calibrator. The probe
should fit snugly into the calibrator probe sleeve yet should not be so tight that
it cannot be easily removed. Avoid any dirt or grit that may cause the probe to
jam into the sleeve. Best results are obtained with the probe inserted to the full
depth of the well. Once the probe is inserted into the well, allow adequate stabi-
lization time to allow the test probe temperature to settle as described above.
Once the probe has settled to the temperature of the well, it may be compared
to the calibrator display temperature. The display temperature should be stable
to within 0.1°C degree for best results.
CAUTION: Never introduce any foreign material into the probe hole of
the insert. Fluids etc. can leak into the calibrator causing damage to the
calibrator or binding and damage to your probe.
9.2 Calibrator Characteristics
There is a temperature gradient vertically in the test well. The heater has been
applied to the block in such a way as to compensate for nominal heat losses out
of the top of the calibrator. However, actual heat losses will vary with design of
the thermometer probes inserted into the calibrator and the temperature. For
best results, insert probe to full depth of well.
9.2.1 Stabilization and Accuracy
The stabilization time of the calibrator depends on the conditions and tempera
-
tures involved. Typically the test well will stabalize to 0.1°C within 5 minutes
of reaching the set-point temperature as indicated by the display. Ultimate sta
-
bility is achieved 10 to 20 minutes after reaching the set temperature.
Inserting a cold probe into a well requires another period of stabilizing depend
-
ing on the magnitude of the disturbance and the required accuracy. For exam
-
ple, inserting a 0.25 inch diameter room temperature probe into a sleeve at
300°C takes 5 minutes to be within 0.1°C of its settled point and takes 10 min
-
utes to achieve maximum stability.
Speeding up the calibration process can be accomplished by knowing how soon
to make the measurement. It is recommended that typical measurements be
35
9 Test Probe Calibration
Calibrating a Single Probe
1.888.610.7664 sales@GlobalTestSupply.com
Fluke-Direct.com
Loading ...
Loading ...
Loading ...