EURAMET Project ‘Report’
Document:
Approved:
G-OPS-TMP-025
Head of Secretariat
Version: 2.0
2012-02-01
1
Report
progress report
2
final report
T - Temperature
Reference No:
1236
3
Subject Field
4
Type of collaboration
4A
In the case of a comparison
Registered as Key comparison (KC) or Supplementary Comparison (SC) in the KCDB:
no
yes
If yes: No. of KC/SC:
Comparison of Measurement Standards
5
Coordinator
Institute/Country:
Metrology Institute of the Republic of Slovenia/University of LjubljanaFaculty of Electrical Engineering/Laboratory of Metrology and Quality (MIRS/UL-FE/LMK)
Name:
Jovan Bojkovski
Phone:
+386 1 4768 798
E-mail:
[email protected]
6
Participating Partners
6A
EURAMET members or associates (Institute’s standard acronym with country code in
brackets) as registered on EURAMET website.
•
•
BOM (MK)
MIRS/UL-FE/LMK (SI)
6B
Institutes not being EURAMET members or associates (Institute’s full name and country in
brackets)
6C
Change of projects partners: (Please indicate here changes of project partners compared to
the previous report)
New project partners
Removed project partners
7
Title of project
Comparison of the realisations of the ITS-90 over the range of 234.3156 K to 692.677 K
8
Progress/Final
The bilateral comparison itself was divided in three phases. In the first phase (performed in
October and November of 2011), one metal sheathed standard platinum resistance thermometer
was calibrated at fixed points (mercury, tin and zinc) at MIRS/UL-FE/LMK (SI). In the second phase
(performed in the period between January and March of 2012), the same measurements were
performed by BOM (MK). After its return, the standard platinum resistance thermometer was
recalibrated (measurements performed in April and May 2012) at MIRS/UL-FE/LMK (SI). The
values of W were compared.
The procedure followed was the same procedure as for EURAMET 552 project.
It was recommended that the participants use their standard procedure during the temperature
EURAMET e.V.
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38116 Braunschweig
Germany
Phone: +49 531 592 1960
Fax:
+49 531 592 1969
[email protected]
www.euramet.org
calibration and if possible avoid making extra time-consuming measurements.
The circulating item was Fluke HartScientific 25 Ω standard platinum resistance (SPRT)
thermometer, metal sheathed, type 5699, and serial number 0370. The diameter of the metal
sheath probe is Ø 5.6 mm. Probe should be immersed in the fixed point at least 170 mm.
After the transport, the measurement at the triple point of water, to check stability, was performed
and reported to the pilot laboratory. Prior to the start of measurements, annealing was performed.
The SPRT was carefully inserted into an annealing furnace at 470 °C, and then annealed for two
hours at 470 °C. After thermal treatment, the SPRT was carefully removed from the annealing
furnace directly to the room environment. The resistance value at the triple point of water was
measured. If the resistance at triple point of water was increasing, the pilot laboratory had to be
contacted immediately. If the decrease in the triple point of water resistance of the SPRT after
annealing was equivalent to 0.5 mK or larger, the annealing procedure was repeated. If the
decrease is less than 0.5 mK laboratory continued with measurements at fixed points.
If the decrease in the triple point of water resistance of the SPRT after second annealing was larger
than 0.2 mK, the pilot laboratory was contacted for further instructions. Otherwise, laboratory
continued with measurements at fixed points.
Prior to the calibration at fixed points in each laboratory, test measurement at the TPW was done in
order to assess stability of the instruments. After the annealing, the SPRT was calibrated at all of
the fixed points in the range of comparison, i.e., measurements at TPW, Zn, TPW, Sn, TPW, Hg,
TPW in that order. Existing techniques as used by the participating laboratory were used
In order to not increase the uncertainty on the comparison of the results the RT values given by the
different participants approximately corresponded to the same percentage of metal in liquid phase,
as described in the protocol of comparison.
For each metal fixed point the W=RT/RTPW was calculated. RTPW is the TPW resistance
measured immediately after the measurement of RT. All the measurements at the fixed points had
been corrected for self-heating, hydrostatic head and, if any, the pressure effect. At least 3 different
phase transitions (3 freezing for Zn, Sn, and 3 triple points for Hg) were performed. All three
measurements for each fixed point were reported in the Excel spreadsheet including the calculated
mean.
MIRS/UL-FE/LMK performed measurements at the beginning of the interlaboratory comparison and
at the end. In the report form, the participants were also asked to fill in details about the applied
method, uncertainty sources, equipment and traceability.
Fixed point W MIRS/UL-FE/LMK Uncertainty MIRS/UL-FE/LMK (mK) W BOM Uncertainty BOM
(mK)
Hg
0.844153731 0.6
0.844155892 2.9
Sn
1.892692908 1.0
1.892696135 3.8
Zn
2.568717035 1.5
2.568738847 6.3
Uncertainty sources for the calibration of SPRT at the freezing point of zinc, in mK
Uncertainty source BOM MIRS/UL-FE/LMK
Repeatability of readings
1.0
0.03
Uncertainty linked with purity 0.56 0.4
Uncertainty linked Hydrostatic pressure correction
Uncertainty linked with perturbing heat exchanges
Uncertainty linked with self-heating correction
Uncertainty linked with bridge linearity
0.67
Uncertainty linked with AC/DC current
0
Uncertainty linked with gas pressure0
0.05
Repeatability of readings
1.1
0.02
EURAMET Projects
0.018 0.012
0.25 0.1
0.2
0.03
0.05
0
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Document:
Approved:
G-OPS-TMP-025
Head of Secretariat
Version: 2.0
2012-xx-xx
Repeatability of temperature realized by cell
0.44
Short repeatability of calibrated SPRT
0.29 0.15
Uncertainty linked with purity and isotopic composition
Uncertainty linked Hydrostatic pressure correction 0.16
Uncertainty linked with perturbing heat exchanges 0.058
Uncertainty linked with self-heating correction
0.15
Uncertainty linked with bridge linearity
1.72 0.05
Uncertainty linked with AC/DC current
0
0
Uncertainty linked with internal insulation leakage 0
Uncertainty linked with stability of RS
0.15 0
Uncertainty linked with temperature of RS 0.15 0.005
Wt scatter
1.75 0.59
Combined uncertainty
Expanded uncertainty
k=2
6.3
1.50
3.15
0.05
0.29 0.05
0.005
0.01
0.03
0
0.75
Further details are avaiable in paper Comparison of The Realisations of The ITS-90 Over The
Range of -38.8344 °C to 419.527 °C J.Bojkovski and O.Petrusova, presented at TEMPMEKO 2013
and submitted for publication in IJT
9
10
In the case of a KC/SC comparison & final report
Final report sent to the appropriate CC WG
no
Report endorsed by the CC WG
no
yes
yes
Expected completion date
2013-06-01
11
Date
2014-03-21
Notes for completion of the form overleaf
EURAMET Projects
3/4
Document:
Approved:
G-OPS-TMP-025
Head of Secretariat
Version: 2.0
2012-xx-xx
NOTES FOR THE COMPLETION OF THE FORM (numbers refer to boxes overleaf)
Forms are to be sent to the EURAMET Secretariat ([email protected]) as word or pdf file
- by the TC Chair or
- by the proposer/coordinator of the project with copy to the TC Chair.
If the proposer/coordinator is not EURAMET TC contact person the national contact person(s) of the relevant
TC(s) have to be involved in the registration process.
2
Ref No: The project reference number which has been assigned by the EURAMET Secretariat and
on which progress is reported; you can find it on the EURAMET website.
3
Subject Field: The field specified in the EURAMET Project Form.
4
Type of collaboration: The field specified in the EURAMET Project Form.
4A
In the case of a comparison:
o
o
o
5
In the case of a KC or a SC to be registered in the KCDB, the coordinator should be aware that
the protocol should be sent to the appropriate CC WG for approval (KC) or for feedback (SC).
In the case of a KC, the comparison can take place only if its protocol has been approved by the
appropriate CC Working Group.
The KC must be compatible and linkable to the parent CC comparison.
Coordinator: The Coordinator is the person who is appointed as the contact point for the project
detailed overleaf.
6A/6B EURAMET members or associates / Institutes not being EURAMET members or associates:
Please indicate here the current list of all collaboration partners. Newly assigned or removed
partners should additionally be listed under 5C
6C
Change of projects partners: Please indicate here the project partners which have changed since
the project has been proposed or agreed or since the last reporting.
7
Title: The title given in the EURAMET Project Form.
8
Progress: A brief description of the progress should be entered in the space provided. Comments
on the advantages of undertaking the work collaboratively through EURAMET would be useful.
Completion of this Report is not deemed as publication of the work. Collaborators are encouraged to
publish their work through normal channels, mentioning it was undertaken as EURAMET
collaboration.
9
Expected completion date: If the progress of a project is being reported on this form then an
estimate of the completion date should be made. If the project has now been completed then the
actual date of completion should be given.
10
Date of transmission to EURAMET Secretariat.
EURAMET Projects
4/4
Document:
Approved:
G-OPS-TMP-025
Head of Secretariat
Version: 2.0
2012-xx-xx