PCE Instruments PCE-COM 20 Bedienungsanleitung Seite 57

1. Calibration of the high value a
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When you are in the calibration menu, a calibration of the block with the high value will be required
first. The set value of this block is marked with a , in the upper part of the display. On the lower, left-
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hand side of the display, the corresponding temperature coefficient will be shown. To calibrate the
device, place the probe on the block's surface vertically and evenly to measure its conductivity.
If the measured value a corresponds to the set value, the high value does not have to be calibrated.
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If you press the "OK" key while holding the probe up (distance to the block >5 cm), the device will
automatically switch to the calibration of the low value a .
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If the measured value a is not the same as the set value, keep the probe placed on the calibration
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block and press "OK". The device will finish the calibration automatically and emit a sound when the
calibration is finished.
Measure this calibration block again. If the displayed value deviates by more than 0.3 %, the
calibration must be repeated until the value is as required. Then hold the probe up (distance to the
block >5 cm) and press "OK" to calibrate the low value.
2. Calibration of the low value a
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Now the low value is calibrated. Again, you will find the set value of the block next to "CAL". Of
course, the value will be lower this time. On the lower left-hand side, you can find the temperature
coefficient for the block.
When the measured value aL is the same as the set value, you do not have to calibrate the low
value.
When the measured value aL is not the same as the set value, keep the probe placed on the
calibration block and press "OK". The device will complete the calibration automatically and emits a
sound when it is finished.
Measure this calibration block again. If the displayed value deviates by more than 0.3 %, the
calibration must be repeated until the value is as required. Then hold the probe up (distance to the
block >5 cm) and press "OK".
3. Cancel calibration
To cancel the calibration during the process, press "MEAS" or "SET". The calibration window will be
closed, all steps taken by then will be deleted and the device will return to the start screen.
4. Additional notes on the calibration
The calibration type for this device is a two-point calibration. This means that a calibration block with
a high value σ σ
and one with a low value is used.
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Selection of the calibration block:
The value of the block with the high value σ
(20) should normally be higher than the value of the
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tested material. The value of the other block σ
(20) should be lower than the value of the material.
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© PCE Instruments
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