Pohranjivanje grupnog etalona otpora primarnog elektromagnetskog laboratorija

doctoral thesis

• Title (english): Maintenance of the Group Standard Resistor in the Primary Electromagnetic Laboratory
• Author: Roman Malarić
• Mentor: Josip Butorac (mentor)
• Committee member: Stanko Milun (član povjerenstva)
• Committee member: Josip Butorac (član povjerenstva)
• Committee member: Božidar Ferković (član povjerenstva)
• Committee member: Mladen Boršić (član povjerenstva)
• Committee member: Borivoj Modlic (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electrical Engineering Fundamentals and Measurements); Zagreb
• Defense date and country: 2001-03-27, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

U doktorskoj disertaciji opisani su postupci pohrane skupnog etalona otpora u Primarnom elektromagmnetskom laboratoriju. Razrađena je metoda usporedbe etalonskih otpornika nazivnih omjera 1:1 i 1:10 pomoću digitalnih voltmetara HP3458A. Mjerni je postupak automatiziran pomoću PC računala te potrebnih kartica i uređaja. Izrađeni su pomoćni uređaji i programi za računalno upravljanje mjerenjem te opisane sve sheme spajanja. Računalo generira i izlazne protokole sa svim potrebnim podacima i obavlja statističku obradu rezultata. Pozornost je dana svim mogućim utjecajima na mjernu nesigurnost. To su termonapon, kontaktni otpori, izolacijski otpor, temperatura, vlažnost i tlak. Za određivanje pogrješke linearnosti voltmetra i za određivanje zagrijavanja etalona pod različitim opterećenjem osmišljene su i posebne metode. Obavljena je procjena mjerne nesigurnosti usporedbe i svakog pojedinog etalona. Razvijene su dvije metode mjerenja, MOEO 1.1 i MOEO 1.2. Metoda MOEO 1.1 pogodnija je pri mjerenju etalona nazivnih vrijednosti do 10 kΩ jer kod nje na rezultate mjerenja ne utječe otpor žice koja spaja etalone. Metoda MOEO 1.2 je pogodnija pri usporedbi etalona većih nazivnih vrijednosti jer kod nje na rezultate mjerenja ne utječu unutarnji otpori voltmetara i izolacijski otpori prema zemlji. Obavljena je analiza vremenskog kretanja svakog pojedinog etalona, a napisan je i program koji esktrapolira vrijednost otpora etalona u vremenskom intervalu do slijedeće usporedbe. Razradom ove metode za usporedbu etalona otpora osigurana je sljedivost etalona otpora u Republici Hrvatskoj, što je i jedna od osnovnih zadaća Primarnog elektromagnetskog laboratorija.

Abstract (english)

The doctoral dissertation describes the maintenance of the of the group resistance standard in the Primary Electromagnetic Laboratory. Two methods are described for the standard resistor comparison for nominal ratios of 1:1 and 1:10 with the help of two digital voltmeters Hewlett Packard 3458A. The measurement procedure is automatized with the help of PC computer and PC controlled cards and devices. All necessary auxiliary devices, programs and schemes have been made and described. The computer does statistical analysis of the results and generates reports with important data. The special attention was given to all uncertainty contributions such as thermal EMF, contact resistances, leakage resistances, temperature, humidity and pressure. The special methods have been developed for the determination of voltmeter linearity error and for determination of the resistor load coefficients. The measurement uncertainty has been estimated, both for the comparison procedure, and for each of the standard resistors. Two measurement methods have been developed: method MOEO 1.1 is more suitable for the comparison of standard resistors up to 10 kΩ, because the connecting wire does not influence the measurement in this method, and the measurement method MOEO 1.2 is more suitable for the comparison of standard resistors with higher nominal value, because in this method the DVM input impedance and the leakage resistances towards the ground do not influence the measurement. The analysis of change through time for all standard resistor and the program for the extrapolation of values into the ‘future’ between the comparisons has been made. With the development of these methods, a system of traceability has been established for the standard resistors in the Republic of Croatia, which is one of the main goals of the Primary Electromagnetic Laboratory.

• Keywords: Usporedba etalona otpora; digitalni voltmetar; automatizacija mjerenja
• Keywords (english): Standard resistor comparison; digital voltmeter; measurement automatization
• Language: croatian
• URN:NBN: urn:nbn:hr:168:774559
• Study programme: Title: Doctoral study programme "Electrical Engineering and Computing"; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, po-dručje tehničkih znanosti (doktor/doktorica znanosti, po-dručje tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2019-04-18 12:36:44