Temperature difference thermometer
Pt100 Model HD
(-100 °C … 660 °C)
Temperature difference thermometer for determining vertical temperature gradients and precise temperature measurement.
- Temperature range: -100 °C tio 660 °C
- Small measurement uncertainties: 6 mK to 25 mK
- Measurement of vertical temperature gradients
- Temperature standard and temperature difference thermometer
The thermometer for temperature difference measurement is a practical tool for daily laboratory work. The thermometer makes work easier when:
- Determining of vertical temperature gradients
Vertical temperature gradients must be measured as part of the measurement uncertainty of a calibration (e.g. according to DKD-R 5-4 “Calibration of block calibrators”, DKD-R 5-3 “Calibration of thermocouples” or DKD-R 5-1 “Calibration of resistance thermometers”).
- Optimising calibration furnaces
When optimising heating zones on calibration furnaces, precise temperature differences must be measured.
- Precise temperature standard
The main measuring point of the differential thermometer corresponds to the design of the eXacal PT 100 H and can be calibrated with the same measurement uncertainties. This means that the differential thermometer can be used not only for measuring temperature differences but also as a temperature standard.
The differential thermometer has two Pt 100 temperature sensors positioned at the bottom of the thermometer and at a distance of 4 cm.
Uncertainty of Measurement
eXacal thermometers can be calibrated in our own DAkkS calibration laboratory. The DAkkS accreditation ensures that all calibrations are traceable to national and international standards.
The calibration of the eXacal resistance thermometers is carried out at ITS-90 fixed points. It is also possible to carry out calibrations according to the comparison method in calibration baths and calibration ovens. The measurement uncertainty is calculated from many components. The largest contributions are reproducibility, ITS-90 characteristic, self-heating and hysteresis.
With the differential thermometer, the main measuring point is calibrated at fixed temperature points. The second measuring point is measured by a differential measurement at maximum immersion depth in a heat pipe with an extremely good vertical profile.
- Small measurement with DAkkS calibration certificate
- Temperature fixed points from mercury triple point -38,8344 °C to aluminium solidification point 660,323 °C
- Differential measurement in a heat pipe / heat pipe furnace
|-38,8344 °C||Mercury triple point||6 mK|
|0,01 °C||Water triple point||6 mK|
|29,7646 °C||Gallium melting point||6 mK|
|156,5985 °C||Indium melting point||10 mK|
|231,928 °C||Tin melting point||11 mK|
|419,527 °C||Zinc melting point||21 mK|
|660,323 °C||Aluminium freezing point||25 mK|
The stated measurement uncertainties correspond to k=2, include an ITS-90 characteristic curve and are given for the respective range.
|Model||eXacal Pt100 HD|
|Temperature range||-100 °C bis 660 °C|
|Nominal resistors||Pt100 (100 Ohm)|
|typical annual drift||2,5 mK|
|Connection||Banana plugs or depending on configuration|
|Handle||∅ 20 mm x 100 mm|
|Connection cable||2 m|
|Measuring resistors / Temperature sensors|
|R0||100 Ohm ± 0,05 Ohm (High-Temperature Measuring resistors)|
|Alpha||0,003850 ± 0,000005|
|Recommended measuring current||1 mA|
|Self heating||4 mK|
|Calibration (main measuring point)|
|Fixed point calibration||6 mK bis 25 mK|
|Comparison calibration||16 mK bis 50 mK|
Questions about Thermometers?