RANCANG BANGUN DAN EVALUASI KINERJA INSTRUMEN pH METER DAN TURBIDITY METER BERBASIS ARDUINO UNO UNTUK PENGUKURAN KUALITAS AIR

Abstract

The availability of affordable water quality measurement instruments is essential for vocational education laboratories with limited budgets. This study aims to design an Arduino Uno-based pH and turbidity meter and evaluate its performance through multi-point calibration and real water sample testing. The system integrates an E-201C pH sensor, a turbidity sensor, a 16×2 LCD, an SD card module, and a buzzer. The pH sensor calibration (pH 4.00–10.01) yielded a linear relationship of  ( ) with a mean relative error of 1.44%. The turbidity sensor calibration (0–1000 NTU) resulted in  ( ), although precision decreased at higher turbidity levels (%RSD up to 5.504%). Testing on tap, well, and river water samples yielded pH values of 7.15, 6.80, and 7.45, and turbidity values of 3.8, 12.5, and 145 NTU, respectively. The prototype demonstrates consistent measurement responses, serving as a viable alternative for educational practical work and small-scale research.