# System design for monitoring REDOX potential in treated water using an ORP sensor

## TL;DR

This paper describes a low-cost system using an ORP sensor and Arduino to monitor water quality in real time at wastewater treatment plants.

## Contribution

The novel contribution is an economical and reliable ORP monitoring system for continuous bacteriological quality assessment in wastewater treatment.

## Key findings

- A properly calibrated ORP sensor provides accurate measurements comparable to traditional lab methods.
- Real-time ORP monitoring enables alerts for microbial load changes, allowing timely corrective actions.
- The system is a cost-effective alternative to conventional bacteriological analysis methods.

## Abstract

Electrodes that measure the oxidation–reduction potential (ORP) assess the relationship between oxidized and reduced substances that may exist in water disinfection processes. This work presents the implementation and characterization of an ORP measurement system using the Atlas Scientific ORP sensor, integrated with an Arduino R4 development board as the control and data transmission unit. The main objective is to develop an economical, fast, and reliable solution for the continuous monitoring of the bacteriological quality of water in a wastewater treatment plant (WWTP). The system operates in real time, transmitting information to remote platforms. The manufacturing and integration stages of the system, as well as its calibration and experimental validation, are described. The results indicate that a properly calibrated sensor provides accurate measurements, making it a viable and cost-effective alternative to traditional laboratory equipment or bacteriological analyses that require long processing times. Additionally, by monitoring the ORP variable in a WWTP, alerts can be generated for variations related to microbial load in the wastewater treatment process, enabling immediate corrective actions before discharge into surface water bodies.