uTrc
|
Calibration PRT
|
0 K
|
10 mK
|
normal
|
1
|
10 mK
|
uTrd
|
Drift - reference thermometer
|
0 K
|
10 mK
|
rectangular
|
1
|
5.8 mK
|
uTrcon
|
Conduction -
reference thermometer
|
0 Ω
|
1.2 mK
|
rectangular
|
1
|
1.2 mK
|
uTca
|
Standard deviation
|
0 K
|
2 mK
|
normal
|
1
|
2 mK
|
uTch
|
DUC Hysteresis
|
0 K
|
1.2 mK
|
rectangular
|
1
|
1.2 mK
|
uTccon
|
DUC Conduction
|
0 K
|
1.2 mK
|
rectangular
|
1
|
1.2 mK
|
uRohm
|
Calibration multimeter
|
0 K
|
10mΩ
|
normal
|
2.5
|
20 mK
|
uRts
|
Time stability multimeter
|
0 K
|
0.5mΩ
|
rectangular
|
2.5
|
1.25 mK
|
uRres
|
Mulrimeter resolution
|
0 K
|
0.5mΩ
|
rectangular
|
2.5
|
1.25 mK
|
uRohmDUC
|
Calibration multimeter
|
0 K
|
10mΩ
|
normal
|
2.5
|
20 mK
|
uRtsDUC
|
Time stability multimeter
|
0 K
|
0.5mΩ
|
rectangular
|
2.5
|
1.25 mK
|
uRresDUC
|
Multimeter resolution
|
0 K
|
0.5mΩ
|
rectangular
|
2.5
|
1.25 mK
|
ubath h
|
Bath homogenity
|
0 K
|
18.4mK
|
normal
|
1
|
18.4mK
|
ubath s
|
Bath stability
|
0 K
|
3.2mK
|
normal
|
1
|
3.2mK
|
Expanded measurement uncertainty U (k=2)
|
72.2mK
|
The above example relate to the calibration of a thermometer at one temperature only. Usually, a thermometer is calibrated at several temperatures (calibration points) for which, as a rule, different measurement uncertainties result. As the user also employs the thermometer to carry out temperature measurements between the calibration points, it is, however, helpful if the calibration certificate also contains statements on the use of the thermometer in the whole temperature range.
At the customer's, the thermometer is possibly used under conditions which are different from those under which the calibration was carried out. So contributions to the measurement uncertainty might dominate which could remain unaccounted for in the calibration. The measurement uncertainty in use can therefore considerably exceed the measurement uncertainty in calibration.
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