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WIKA operating instructions, model CTH6200
EN
2146872.02 07/2021 EN/DE
▶
To disconnect the temperature probe, do not pull on the cable, but rather only on the
connector sleeve.
4.6.3 General information on temperature probes
Heat dissipation through probe construction
Especially for measurements of temperatures that deviate extremely from the ambient
temperature, measurement uncertainties occur if the heat dissipation through the probe
is not taken into account. For this reason, measurements in liquids should be immersed
sufficiently deep and then stirred. When measuring gases, the probe tube should
protrude as far as possible into the gas to be measured (e.g. for duct measurements) and
the gas should flow around the probe as strongly as possible.
Permissible probe temperature range
Pt100 sensors are suitable for very wide temperature ranges. The permissible
temperature limits of the probe used must be observed. Exceeding the permissible range
usually provides an inaccurate measuring result, or the probe may even be permanently
damaged!
When measuring high temperatures, the probe tube length should be long enough that
the temperature at the handle remains low.
Self-heating
The measuring current used is only 0.3 mA. This means that in practice the sensor
heating of even very small sensor elements is negligible.
Evaporative cooling
When measuring the air temperature, the probe should be dry, otherwise the temperature
measured will be too low (cooling through evaporation).
4. Design and function
