Comparison
Comparison close
Results

CCEM-K3 and EUROMET.EM-K3

MEASURAND : Inductance at frequency 1 kHz
NOMINAL VALUE : 10 mH

Degrees of equivalence Di and expanded uncertainty Ui (k = 2)
Li/LR ~ 1 + Di x 10-6

Red diamonds: participants in CCEM-K3
Blue circles: participants in EUROMET.EM-K3

Comparison
Comparison close
Results

CCEM-K3 and EUROMET.EM-K3

MEASURAND : Inductance at frequency 1 kHz
NOMINAL VALUE : 10 mH

Degrees of equivalence Di and expanded uncertainty Ui (k = 2)
Li/LR ~ 1 + Di x 10-6

   
Lab iDiUi
ASMW/PTB-B-38
BNM-LCIE-415
IEN015
NIM89
NIST038
NPL-721
METAS-1775
PTB-BS629
SP-1938
UME-912
VNIIM07
BIM-1641
INM(RO)-2661

The Uij value in the degree of equivalence between METAS and NPL takes into account the correlation between the results of these two laboratories (value indicated by *).

BIM and INM(RO) participated in key comparison EUROMET.EM-K3 only.

The full matrix of equivalence is available in Summary Results (PDF file).

Comparison
Comparison close
CC comparison
Linked comparison
EUROMET.EM-K3
Metrology area, Sub-field Electricity and Magnetism, Inductance
Description Comparison of inductors
Time of measurements 2006
Status Approved for equivalence
Final Reports of the comparisons
Measurand Inductance: 10 mH
Parameters Frequency: 1 kHz
Transfer device Thermostated commercial inductance standard
Comparison type Key Comparison
Consultative Committee CCEM (Consultative Committee for Electricity and Magnetism)
Conducted by EURAMET (European Association of National Metrology Institutes)
RMO Internal Identifier EUROMET Project No 889
Comments

Results published on 13 June 2011

EUROMET.EM-K3 results are linked to those of CCEM-K3

Inductance at frequency 1 kHz

Pilot institute PTB
Physikalisch-Technische Bundesanstalt
Germany
Contact person J. Melcher
noemail2@ptb.de
+49 (0) 513 592 2100
First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory
PTB

Physikalisch-Technische Bundesanstalt, Germany, EURAMET

INM

National Institute of Metrology, Romania, EURAMET

NCM

National Centre of Metrology, now BIM (Bulgarian Institute of Metrology), Bulgaria, EURAMET

Comparison
Comparison close
Results

CCEM-K3 and EUROMET.EM-K3

MEASURAND : Inductance at frequency 1 kHz
NOMINAL VALUE : 10 mH

  • Key comparison CCEM-K3

The key comparison reference value LR of this comparison is
LR = L0(1 + mR x 10-6), with L0 = 10 mH. mR is obtained from the weighted mean of the participant results (except METAS and UME), using weights proportional to the reciprocal of the quadratic sum of the uncertainty of the laboratories and the transfer uncertainty. The standard uncertainty uR of mR is the standard uncertainty of this weighted mean. It takes into account the uncertainty due to the travelling standards:
mR = 452, uR = 2.

The degree of equivalence of each laboratory with respect to the reference value is given by a pair of terms:
Di = mi - mR and its expanded uncertainty (k = 2) Ui = 2(ui+t2 - uR2)1/2 (except for METAS and UME). Li/LR ~ 1 + Di x 10-6.

The degree of equivalence between two laboratories i and j is given by a pair of terms:
Dij = Di - Dj = (mi - mj) and its expanded uncertainty (k = 2), Uij,
Uij = 2(ui+t2 + uj+t2)1/2.

  • Key comparison EUROMET.EM-K3

PTB or PTB (ASMW) participated in both comparisons CCEM-K3 and EUROMET.EM-K3, making possible to link the results of BIM and INM(RO), participants in EUROMET.EM-K3 only, to those of CCEM-K3 (see Section 4.2 of the EUROMET.EM-K3 Final Report).
No pair-wise degrees of equivalence involving participants in EUROMET.EM-K3 have been computed.

Comparison
Comparison close
Results

CCEM-K3 and EUROMET.EM-K3

MEASURAND : Inductance at frequency 1 kHz
NOMINAL VALUE : 10 mH

  • Key comparison CCEM-K3

mi : result of the measurement carried out by laboratory i, given as the relative difference from the nominal value, Li = L0(1 + mi x 10-6) with L0 = 10 mH

ui : combined standard uncertainty of mi reported by laboratory i

ut : estimated standard uncertainty of mi due to the travelling standards
The transfer uncertainty of the travelling standards ut is estimated from the standard deviation of one observation of the results of the long-time measurements at the pilot laboratory, the PTB, from 1989 to 1999: ut = 3.5

ui+t : total standard uncertainty of mi

 Lab i mi ui ui+t Date of measurement
 ASMW/PTB-B* 449 3 4 89-10 ... 99-10
 BNM-LCIE 449 7 8 91-04
 IEN 452 7 8 91-10 ... 92-03
 NIM 460 4 5 89-11
 NIST 452 19 19 94-08
 NPL 445 10 11 90-08 ... 91-04
 METAS 436 38 38 91-06
 PTB-BS** 458 15 15 90-05
 SP 434 19 19 90-07
 UME 443 5 6 98-10
 VNIIM 452 2 4 89-11


*ASMW/PTB-B: ASMW up to 1990 and PTB in Berlin after 1990
**PTB-BS: PTB in Braunschweig
  • Key comparison EUROMET.EM-K3

Results obtained by participants in EUROMET.EM-K3 are given in Table 2 on page 9 of the EUROMET.EM-K3 Final Report.