• Abstract
• How to cite
• Metrics
• References

• Purpose of the study: This study aims to evaluate and compare the reading accuracy of a TDS sensor when interfaced with Arduino UNO and ESP32 microcontrollers, specifically in the context of water clarity measurement applications, by assessing voltage reading precision, data acquisition stability, and measurement consistency across varying dissolved solids concentrations.

  Methodology: Hardware used includes a TDS sensor, Arduino UNO (ATmega328P, 10-bit ADC), ESP32 NodeMCU (12-bit ADC), and a calibrated TDS meter as the reference instrument. The study employs the Waterfall methodology with direct laboratory observation, potentiometer testing, and voltage measurement across water samples at concentrations of 101, 201, 300, 406, and 515 PPM, each repeated three times at room temperature (~20–21°C).

  Main Findings: Arduino UNO demonstrated superior accuracy with average voltage errors ranging from 0.21% to 2.12% across all TDS concentrations, compared to ESP32's errors of 13.1% to 54.32%. The ESP32 critically misread a 101 PPM water sample as 48 PPM, yielding a 54.32% error — a failure that would result in a misclassification of water clarity category. Arduino UNO's standard deviation was 0.064 ADC versus ESP32's 2.019 ADC, confirming 31.5 times greater measurement stability.

  Novelty/Originality of this study: This study offers a direct, multi-parameter comparison of Arduino UNO and ESP32 specifically for TDS-based water clarity measurement, exposing a critical non-linearity flaw in the ESP32's ADC performance at low-voltage ranges (<10% Vref) that has not been previously documented in this application context.

• How to cite

  [1]

  “Analysis of the TDS Sensor Reading Accuracy Between Arduino Uno and ESP32 Microcontrollers for Water Clarity Measurement”, In. Sci. Ed. J, vol. 7, no. 4, pp. 773–783, Jul. 2026, doi: 10.37251/isej.v7i4.3531.

  More Citation Formats

  • ACM
  • ACS
  • APA
  • ABNT
  • Chicago
  • Harvard
  • IEEE
  • MLA
  • Turabian
  • Vancouver
• 6

  Abstract views

  1

  Downloads

  ---

  Metrics — Badges
• 1. [1] W. J. Hong, N. Shamsuddin, E. Abas, R. A. Apong, Z. Masri, H. Suhaimi, S. H. Godeke, and M. N. A. Noh, “Water quality monitoring with arduino based sensors,” Environments, vol. 8, no. 1, pp. 6, 2021, doi: 10.3390/environments8010006.
  2. [2] K. Lal, S. Menon, F. Noble, and K. M. Arif, “Low-Cost IoT based system for lake water quality monitoring,” PLOS ONE, vol. 19, no. 3, pp. 0299089, 2024, doi: 10.1371/journal.pone.0299089.
  3. [3] C. Chuzaini and D. Dzulkiflih, “IoT monitoring kualitas air dengan menggunakan sensor suhu, ph, dan total dissolved solids (TDS) [IoT monitoring of water quality using temperature, pH, and total dissolved solids (TDS) sensors],” Jurnal Inovasi Fisika Indonesia (IFI), vol. 11, no. 3, pp. 46-56, 2022.
  4. [4] M. Tansa, “Monitoring kualitas air sungai (kekeruhan, suhu, tds, ph) menggunakan mikrokontroler Atmega328 [Monitoring river water quality (turbidity, temperature, TDS, pH) using the Atmega328 microcontroller],” Jambura Journal of Electrical and Electronics Engineering, vol. 6, no. 1, 2024, doi:10.37905/jjeee.v6i1.23315
  5. [5] N. D. Susanti, D. Sagita, I. F. Apriyanto, C. E. W. Anggara, D. A. Darmajana, and A. Rahayuningtyas, "Design and Implementation of Water Quality Monitoring System (Temperature, pH, TDS) in Aquaculture Using IoT at Low Cost," in Proc. 6th Int. Conf. Food, Agriculture, and Natural Resource (IC-FANRES 2021), Atlantis Press, 2022, pp. 7–11.
  6. [6] Y. Adityas et al., "Water quality monitoring system with parameter of ph, temperature, turbidity, and salinity based on internet of things," Jurnal Informatika dan Sains (JISA), vol. 4, no. 2, pp. 138–143, 2021, doi: 10.31326/jisa.v4i2.965.
  7. [7] S. R. Laha, B. K. Pattanayak, and S. Pattnaik, “Advancement of environmental monitoring system using IoT and sensor: a comprehensive analysis,” AIMS Environmental Science, vol. 9, no. 6, pp. 771-800, 2022, doi: 10.3934/environsci.2022044
  8. [8] Medagedara, O. V., & Liyanage, M. H. (2024). Development of an IoT-based Real-Time Temperature and Humidity Monitoring System for Factory Electrical Panel Rooms. Engineering Journal of Institute of Engineers Sri Lanka, 57(1), 21-30, 2024, doi: 10.4038/engineer.v57i1.7636
  9. [9] S. Salehin, T. A. Meem, A. J. Islam, and N. Al Islam, "Design and development of a low-cost IoT-Based water quality monitoring system," in Lecture Notes in Electrical Engineering, vol. 980, Springer, Singapore, 2023, pp. 697–706, doi: 10.1007/978-981-19-8032-9_51.
  10. [10] M. Babiuch, P. Foltynek, and P. Smutny, "Using the ESP32 Microcontroller for Data Processing," MATEC Web of Conferences, vol. 292, p. 01011, 2019, doi: 10.1051/matecconf/201929201011.
  11. [11] A. Saric, K. Dokic, and M. Cobovic, "Performance Evaluation of C/C++, MicroPython, Rust and TinyGo Programming Languages on ESP32 Microcontroller," Electronics, vol. 12, no. 1, p. 143, Dec. 2022, doi: 10.3390/electronics12010143.
  12. [12] M. Truntic and O. Tezak, “Design and Implementation of ESP32-Based IoT Devices,” Sensors, vol. 23, no. 15, p. 6739, 2023, doi: 10.3390/s23156739.
  13. [13] I. Rinaldi, A. Depari, P. Ferrari, A. Flammini, A. Musatti, and E. Sisinni, “Characterization and Performance Evaluation of ESP32 for Real-Time Synchronized Sensor Networks,” Procedia Computer Science, vol. 238, pp. 104–113, 2024, doi: 10.1016/j.procs.2024.05.104.
  14. [14] M. S. Bakare, and K. Abubaker, “IoT-based indoor environmental monitoring system using multi-parameter sensing and ESP32-WROOM integration,” Discover Electronics, vol. 3, no. 1, pp. 6, 2026, doi: 10.1007/s44291-026-00157-3.
  15. [15] H. Fan, Z. Chen, T. Xu, et al. “14-Bit SAR ADC with On-Chip Digital Bubble Sorting Calibration Technology,” Chinese Journal of Electronics, vol. 34, no. 1, pp. 125-136, 2025. doi: 10.23919/cje.2023.00.307.
  16. [16] H. Fan, Z. Chen, T. Xu et al., "14-Bit SAR ADC with On-Chip Digital Bubble Sorting Calibration Technology," Chinese Journal of Electronics, vol. 34, no. 1, pp. 125–136, 2025, doi: 10.23919/cje.2023.00.307.
  17. [17] M. Grossi, “Efficient and accurate analog voltage measurement using a direct sensor-to-digital port interface for microcontrollers and field-programmable gate arrays,” Sensors, vol. 24, no. 3, pp. 873, 2024, doi: 10.3390/s24030873.
  18. [18] T. Islam, M. S. Ahmed, and M. H. Rahman, “ADC non-linearity effects on low-voltage sensor measurements in embedded systems: a systematic review,” IEEE Sensors Journal, vol. 24, no. 5, pp. 6781–6793, 2024, doi: 10.1109/JSEN.2024.3356129.
  19. [19] Y. Wang, Z. Liu, and X. Chen, “Voltage reference stability and its impact on analog sensor accuracy in microcontroller-based systems,” Measurement, vol. 225, pp. 114023, 2024, doi: 10.1016/j.measurement.2023.114023.
  20. [20] F. Karimi, A. Bagheri, and M. R. Mosavi, “Water clarity assessment using TDS sensors: calibration, compensation, and performance evaluation across multiple platforms,” Environmental Monitoring and Assessment, vol. 196, no. 3, p. 274, 2024, doi: 10.1007/s10661-024-12274-3.
  21. [21] M. Hamidatou, N. Chellal, and M. Benbouzid, “A review on tds measurement techniques for water quality monitoring: accuracy, sensitivity, and practical considerations,” Water, vol. 15, no. 11, pp. 2034, 2023, doi: 10.3390/w15112034.
  22. [22] I. Essamlali, H. Nhaila, and M. El Khaili, "Advances in Machine Learning and IoT for Water Quality Monitoring: A Comprehensive Review," Heliyon, vol. 10, no. 6, p. e27920, Mar. 2024, doi: 10.1016/j.heliyon.2024.e27920.
  23. [23] L. Rocher, E. Viala, and C. Roux, “Low-cost water quality sensors for IoT: a systematic review,” Sensors, vol. 23, no. 10, p[. 4853, 2023, doi: 10.3390/s23104853.
  24. [24] A. Rao, P. Kumar, and S. Sharma, “Comparative performance of low-cost microcontrollers for analog sensor interfacing in environmental monitoring applications,” Sensors and Actuators A: Physical, vol. 358, pp. 114415, 2023, doi: 10.1016/j.sna.2023.114415.
  25. [25] H. M. Forhad, M. R. Uddin, R. S. Chakrovorty, A. M. Ruhul, et al, IoT based real-time water quality monitoring system in water treatment plants (WTPs),” Heliyon, vol. 10, no. 23, 2024, doi: 10.1016/j.heliyon.2024.e40746.
  26. [26] A. Junaidi, et al., "Measurement of Physical Parameters of Water Quality in Real-Time Based on Arduino," Journal of Physics: Conference Series, vol. 1751, no. 1, p. 012067, 2021, doi: 10.1088/1742-6596/1751/1/012067.
  27. [27] M. Hidayatullah, S. Sofyan, P. A. Topan, T. Andriani, and N. Nurhairunnisah, “Monitoring system of water quality on hydroponic planting media using total dissolved solid (TDS) sensor based Arduino Uno R3,” Jurnal Ilmu Fisika| Universitas Andalas, vol. 14, no. 2, pp. 108-115, 2022, doi: 10.25077/jif.14.2.108-115.2022.
  28. [28] S. Laha, S. R. Pattanayak, and B. K. Pattnaik, “Advancement of environmental monitoring system using IoT and sensor: a comprehensive analysis,” AIMS Environmental Science, vol. 9, no. 6, pp. 771–800, 2022, doi: 10.3934/environsci.2022044.
  29. [29] D. Abimanyu, S. Sumarno, F. Anggraini, I. Gunawan, and I. Parlina, “Rancang bangun alat pemantau kadar ph, suhu dan warna pada air sungai berbasis mikrokontroller arduino [Design and construction of a tool to monitor pH, temperature and color levels in river water based on an Arduino microcontroller],” Jurnal Pendidikan dan Teknologi Indonesia, vol. 1, no. 6, pp. 235-242, 2021, doi: 10.52436/1.jpti.55.
  30. [30] M. N. Nizam, H. Yuana, and Z. Wulansari, “Mikrokontroler ESP32 sebagai alat monitoring pintu berbasis web [ESP32 microcontroller as a web-based door monitoring tool],” JATI (Jurnal Mahasiswa Teknik Informatika), vol. 6, no. 2, pp. 767-772, 2022, doi: 10.36040/jati.v6i2.5713
  31. [31] S. Baco, R. Syarifuddin, S. Sajiah, M. A. Rusli, and M. D. Loilatu, “Rancang bangun alat monitoring ph air layak konsumsi berbasis mikrokontroller arduino uno pada depot air minum adipura 1 [Design and construction of a pH monitoring device for potable water based on an Arduino Uno microcontroller at the Adipura 1 drinking water depot],” Jurnal Teknologi dan Komputer (JTEK), 3(02), 339-345, 2023, doi: 10.56923/jtek.v3i02.147.
  32. [32] D. Chen, X. Cui, Q. Zhang, D. Li, W. Cheng, C. Fei, and Y. Yang, ”A survey on analog-to-digital converter integrated circuits for miniaturized high resolution ultrasonic imaging system,” Micromachines, vol. 13, no. 1, pp. 140, 2022, doi: 10.3390/mi13010140.
  33. [33] A. H. El-Khozondar, E. H. Bayoumi, and A. A. E. A. Halim, "A smart energy monitoring system using esp32 microcontroller," e-Prime - Advances in Electrical Engineering, Electronics and Energy, vol. 9, pp. 100666, 2024, doi: 10.1016/j.prime.2024.100666.
  34. [34] F. Almajed, F. Almajed, and Q. A. Al-Haija, “An IoT-enabled intelligent water quality monitoring system for tourist safety using machine learning,” Discover Electronics, Springer Nature, vol. 2, no. 1, 2025, doi: 10.1007/s44291-025-00070-1.
  35. [35] Y. H. Chang, F. C. Wu, and H. W. Lin, “Design and implementation of ESP32-based edge computing for object detection," Sensors, vol. 25, no. 6, pp. 1656, 2025, doi: 10.3390/s25061656.
  36. [36] V. K. Tran, B. T. Thai, H. Pham, V. K. Nguyen, and V. K. Nguyen, “A proposed approach to utilizing ESP32 microcontroller for data acquisition," Journal of Engineering and Technological Sciences, vol. 56, no. 4, pp. 474–488, 2024, doi: 10.5614/j.eng.technol.sci.2024.56.4.4.
  37. [37] M. Alselek, J. M. Alcaraz-Calero, J. Segura-Garcia, and Q. Wang, “Water iot monitoring system for aquaponics health and fishery applications,” Sensors, vol. 22, no. 19, pp. 7679, 2022, doi: 10.3390/s22197679.
  38. [38] C. Cohen-Manrique, S. Camacho-Leon, and J. L. Villa, ”Emerging trends in IoT for aquatic systems: a systematic literature review,” Frontiers in Water, vol. 7, pp. 1699240, 2025, doi: 10.3389/frwa.2025.1699240.
  39. [39] C. Axiotidis, E. Konstantopoulou, and N. Sklavos, “A wireless sensor network IoT platform for consumption and quality monitoring of drinking water,” Discover Applied Sciences, vol. 7, no. 1, pp. 15, 2024, doi: 10.1007/s42452-024-06384-1.
  40. [40] A. Boussaha et al., "Development of an IoT-based multi-level system for real-time water quality monitoring in industrial wastewater," Discover Water, Springer, 2024, doi: 10.1007/s43832-024-00092-y.
  41. [41] C. Axiotidis et al., "A wireless sensor network iot platform for consumption and quality monitoring of drinking water," Discover Applied Sciences, Springer, Dec. 2024, doi: 10.1007/s42452-024-06384-1.
  42. [42] R. Moshawrab, M. Adda, A. Bouzouane, H. Ibrahim, and A. Raad, "IoT in water quality monitoring—are we really here?," Sensors, vol. 23, no. 2, p. 960, Jan. 2023, doi: 10.3390/s23020960.
  43. [43] J. Tang, H. Lin, and Q. Tian, "Design and realization of a water quality monitoring system based on the internet of things," Water Practice and Technology, vol. 19, no. 9, pp. 3538–3554, Sep. 2024, doi: 10.2166/wpt.2024.222.
  44. [44] S. Geetha and S. Gouthami, "Internet of things enabled real time water quality monitoring system," Smart Water, Springer, vol. 2, no. 1, pp. 1–19, 2017, doi: 10.1186/s40713-017-0005-y.
  45. [45] O. V. Medagedara and M. H. Liyanage, "Development of an IoT-based real-time temperature and humidity monitoring system for factory electrical panel rooms," Engineering Journal of Institute of Engineers Sri Lanka, vol. 57, no. 1, pp. 21–30, 2024, doi: 10.4038/engineer.v57i1.7636.
  46. [46] M. A. Al-Qurashi et al., "IoT-based real-time water quality monitoring system in water treatment plants (WTPs)," Heliyon, Elsevier, Nov. 2024, doi: 10.1016/j.heliyon.2024.e38459.
  47. [47] O. Habboush et al., "Design of a smart hydroponics monitoring system using an esp32 microcontroller and the internet of things," MethodsX, vol. 11, p. 102418, Dec. 2023, doi: 10.1016/j.mex.2023.102418.
  48. [48] N. A. Cloete, R. Malekian, and L. Nair, "Design of smart sensors for real-time water quality monitoring," IEEE Access, vol. 4, pp. 3975–3990, 2016, doi: 10.1109/ACCESS.2016.2592958.
  49. [49] J. J. Correa-Quiroz, M. A. Toribio-Barrueto, and C. Castro-Vargas, “IoT system with ESP32 for smart drip irrigation and climate monitoring in greenhouses," Emerging Science Journal, vol. 6, no. 5, 2022, doi: 10.28991/ESJ-2022-06-05-01.
  50. [50] S. D. Kalamaras, M. A. Tsitsimpikou, C. A. Tzenos, A. A. Lithourgidis, D. S. Pitsikoglou, and T. A. Kotsopoulos, “A Low-Cost IoT system based on the ESP32 microcontroller for efficient monitoring of a pilot anaerobic biogas reactor," Applied Sciences, vol. 15, no. 1, pp. 34, 2024, doi: 10.3390/app15010034.

Categories

• Applied Science
• Environmental Science & Sustainable Development