Velleman-Kit K2649 Illustrated Assembly Manual page 13

Sensor
14. Sensor
Calibration is performed by alternately adjusting the meter at the freezing respectively boiling-point of water.
Therefore the sensor first has to be prepared.
DON'T shorten the connection wires of the sensor, unless you are not going to fit it directly onto the pcb in
the future.
Solder two isolated wires (75 cm or 30") to the sensor (see fig. 3.0)
Fig. 3.0
Make use of a cable of the desired length (max 10m, and preferably screened to avoid interferences) if you
are not going to fit the sensor onto the pcb in the future.
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