U ovom radu opisana je primjena i princip rada različitih uređaja za mjerenje protoka. Isto tako, provedeno je mjerenje protoka turbinskim i ultrazvučnim mjeračem protoka te Venturijevom cijevi, pri tome je turbinski protokomjer poslužio kao kalibracijski uređaj kako bi se ocjenila točnost ulatrazvučnog protokomjera LRF-2000H tvrtke Longrun Industrial Instrument Co., Ltd, te ispitatala njegovu pouzdanost. Za izvođenje ispitivanja bilo je potrebno instalirati laboratorijsku opremu: crpku te uređaje za mjerenje tlaka i protoka. U radu je opisana sva laboratorijska oprema i sve njene karakteristike. Nakon eksperimentalne analize i statističke obrade dobivenih podataka, numerički je analiziran cjelokupni laboratorijski postav s privodnim cijevima, pumpama itd.. Sustav je numerički analiziran upotrebom softvera AFT Fathom. Provedbom analize, ulatrazvučnog protokomjera LRF-2000H tvrtke Longrun Industrial Instrument Co., Ltd, po potrebi je kalibriran te je utvrđena njegova pouzdanost.This paper describes the application and operation principle of various flow measurement devices. Also, turbine flow measurement and ultrasonic flowmeter and Venturi tubes were performed, where the turbine flowmeter used as a calibration device to estimate the accuracy of the Longrun Industrial Instrument Co., Ltd LRF-2000H ultrasonic flowmeter, and investigated its reliability. To perform the test, it was necessary to install the lab equipment: the pump and the pressure and flow measuring devices. All laboratory equipment and all its features are described in the paper. After the experimental analysis and statistical processing of the data obtained, the system was analyzed numerically by the whole labaratory setup with entraining pipes, pumps, etc. The system is numerically analyzed using the AFT Fathom software. By conducting an analysis, the Longrun Industrial Instrument Co., Ltd.'s LRF-2000H ultrasonic flowmeter has been calibrated and its reliability is determined
