• Please make sure that the external sensor has contact with the soldered PCB.
    Due to the thermal inertia of the PCB, the sensor should not be placed over copper planes. It can be on a pad if that pad is not covered with solder paste (otherwise soldering will damage the sensor). Best it is placed on the solder mask free from copper underneeth (if this is not possible and heavy copper is there, you might need to adjust the temperature correction factor – see temperature correction.).


Correct placement of the sensor on the PCB

Sensor placed correctly on the PCB



Sensor not touching the PCB

Sensor not correctly placed – not touching


  • The graphic lines of the sensors should look seamless. Steep and unexpected variations in measurements mean measurement errors.


Seamless graphic lines

Graph showing seamless lines


  • Line variations for the furnace and pre heater are not possible, due to the construction of the sensors. When the external sensor line shows variations then it is possible that the sensor makes no or a bad contact with the PCB.


  • A ragged line means a bad contact usually by vibrating the sensor, due to the air stream.


Graphic lines not seamless

Graph showing lines not seamless


  • For fixing of the external sensor we recommend an adhesive Capton tape.

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