QUALITY AND CONFIDENCE ASSURANCE IN ELECTRICAL QUANTITIES MEASUREMENTS – RESULTS OF FEIT–HTT INTER-LABORATORY COMPARISON
A b s t r a c t: According to ISO/IEC 17025 a laboratory shall have quality control procedures for monitoring
the validity of tests and calibrations undertaken, through participation in inter-laboratory comparisons (ILC) or profi-
ciency testing programmes (PT). This practice should be a periodic activity and in accordance with the international
standards. In the paper the results of the international ILC conducted by the Laboratory of Electrical Measurements
(LEM) of the Faculty of Engineering and Information Technologies at the Ss. Cyril and Methodius University in
Skopje, R. Macedonia (pilot laboratory), and the High Tech Test shpk – Tirana, R. Albania (HTT), both accredited
laboratories, will be presented. The ILC accomplished in the period March–April 2017 was conducted through cali-
bration of 61⁄2 digital multimeter Keysight 34401A for various electrical quantities. In the paper, the detailed meas-
urement procedure followed by the two laboratories as well as the evaluation and acceptance criteria will be given.
The results of the ILC will be presented and discussed. The ILC gives a significant contribution the quality and con-
fidence assurance in electrical quantities measurements at national and regional/international level.
Key words: inter-laboratory comparison; proficiency testing; calibrations; metrology of electrical quantities; quality assurance
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