RS485 Modbus pH Sensor for Industrial Water Monitoring

Key Features

Continuous online pH and water temperature measurement
Industrial pH electrode for long-term water quality monitoring
Easy integration with PLC, DCS, RTU, data logger and IoT gateway
Automatic temperature compensation for more stable measurement
Suitable for immersion, tank and flow-through installation
Waterproof design for permanent field deployment
Supports remote monitoring, threshold alarms and historical data analysis
Suitable for single-parameter and multi-parameter water quality systems
Cable length, communication settings and system integration can be customized

Product Description

JW-PHG-406(K03) online pH sensor is designed for continuous measurement of pH values in industrial water monitoring, wastewater treatment and environmental water quality applications.

The sensor provides stable and reliable pH measurement for processes that require real-time monitoring and automatic data transmission.

With RS485 Modbus communication, digital signal output and industrial-grade protection design, the online pH sensor can be integrated with:

PLC systems
RTU data loggers
SCADA systems
IoT gateways
Cloud monitoring platforms

Typical applications include:

Process water management
Industrial wastewater treatment
Chemical process monitoring
Water treatment systems
Aquaculture water monitoring
Environmental monitoring stations

What Is an Online pH Sensor?

An online pH sensor is a water quality monitoring device used to continuously measure the acidity or alkalinity of water.

The pH value indicates hydrogen ion concentration and is one of the most important parameters in water quality analysis.

Industrial operators use pH monitoring for:

Chemical dosing control
Wastewater neutralization
Biological treatment processes
Industrial process control
Environmental compliance

Compared with laboratory testing, online pH monitoring provides:

Real-time measurement
Continuous data collection
Faster response to abnormal conditions
Remote monitoring capability

For complete water quality monitoring projects, JW-IoT also provides other sensors including:

water quality sensors

such as dissolved oxygen, ORP, conductivity and turbidity sensors.

How Does an Industrial pH Sensor Work?

An online pH sensor uses a glass electrode and reference electrode system to measure hydrogen ion activity in water.

The measurement process:

Water Sample

↓

pH Glass Electrode

↓

Reference Electrode Signal

↓

Temperature Compensation

↓

Signal Processing

↓

RS485 Modbus Output

↓

Monitoring Platform

The digital measurement data can be transmitted continuously to industrial automation systems.

For projects requiring multiple water parameters, JW-IoT provides integrated solutions combining:

pH sensors
ORP sensors
DO sensors
EC sensors
Turbidity sensors

Why Is Continuous pH Monitoring Important?

1. Maintain Process Stability

Many industrial processes require accurate pH control.

Examples:

Chemical production
Water treatment
Food processing
Pharmaceutical manufacturing

2. Improve Wastewater Treatment Efficiency

pH directly affects:

Biological activity
Chemical reactions
Neutralization processes

JW-IoT provides complete:

industrial wastewater monitoring solutions

including water quality sensors, data acquisition devices and remote monitoring platforms.

3. Reduce Manual Testing

Traditional water testing requires:

Sample collection
Laboratory testing
Manual recording

Online monitoring reduces inspection frequency and provides continuous historical data.

Applications of Online pH Sensor

Industrial Wastewater pH Monitoring

Industrial wastewater may contain acidic or alkaline substances that require continuous monitoring.

Typical applications:

Wastewater treatment plants
Neutralization tanks
Discharge monitoring
Chemical wastewater processes

A complete wastewater monitoring system may include:

pH sensor
ORP sensor
Dissolved oxygen sensor
Conductivity sensor
Turbidity sensor

Water Treatment Process Monitoring

pH measurement is widely used in:

Drinking water treatment
Industrial water purification
Cooling water systems
Filtration systems

For smart water projects, JW-IoT provides:

Water Quality Monitoring Solutions

supporting remote data acquisition and cloud monitoring.

Chemical Industry Applications

Chemical processes often require precise pH control.

Applications include:

Acid-base neutralization
Chemical reaction monitoring
Process water control
Wastewater discharge monitoring

The online pH sensor helps operators maintain stable production conditions and improve process safety.

Aquaculture Water Quality Monitoring

pH is a critical parameter for fish and shrimp farming.

Online pH monitoring supports:

Fish farms
Shrimp ponds
Hatcheries
Recirculating aquaculture systems

For complete aquaculture monitoring, JW-IoT also provides:

dissolved oxygen sensors

and other water quality sensors.

A complete system can monitor:

pH
Dissolved oxygen
Temperature
Conductivity

Environmental Water Monitoring

Online pH sensors are commonly installed in:

Rivers
Lakes
Reservoirs
Surface water stations

Combined with IoT communication technology, monitoring teams can remotely review water quality trends.

JW-IoT provides:

remote environmental monitoring solutions

for smart water and environmental projects.

RS485 Modbus Online pH Monitoring System

A complete industrial pH monitoring architecture includes:

Online pH Sensor

↓

RS485 Modbus

↓

RTU / Data Logger

↓

4G / LoRaWAN / Ethernet

↓

Cloud Platform

↓

Remote Dashboard

The sensor can integrate with:

PLC systems
SCADA systems
IoT gateways
Cloud platforms

For projects requiring wireless communication, JW-IoT supports:

4G LTE
LoRaWAN
Ethernet
MQTT

Learn more about JW-IoT IoT monitoring solutions:

IoT Environmental Monitoring Solutions

Installation Guide

Recommended Installation

For accurate pH measurement:

✔ Keep sensing area fully immersed

✔ Install in representative water conditions

✔ Avoid air bubbles on electrode surface

✔ Provide easy maintenance access

ProduSensor Maintenance

Recommended maintenance:

Clean electrode surface regularly
Perform calibration when required
Check cable connection
Replace electrode when necessary

For long-term water monitoring, proper maintenance improves measurement accuracy and sensor lifetime.

Technical Specifications

Item	Specification
Product Type	Online pH Sensor
Measurement Principle	Glass electrode method
Measuring Range	0–14.00 pH
Resolution	0.01 pH
Accuracy	±0.1 pH ±0.3°C
Response Time	T90 less than 30s
Minimum Detection Limit	0.1 pH
Calibration	Two-point calibration
Temperature Compensation	Automatic Pt1000 compensation
Output	RS485 Modbus RTU optional 4–20mA
Power Supply	12–24V DC
Power Consumption	0.2W at 12V
Protection Rating	IP68
Working Conditions	0–50°C ≤0.2MPa
Installation	Immersion installation 3/4 NPT thread
Cable Length	5 m standard customizable
Housing Material	POM ABS or POM 316L stainless steel

The final specification should be confirmed according to the selected electrode, water conditions, communication requirements and installation method.

How to Select an Industrial pH Sensor?

Before selecting a sensor, consider:

1. Application Environment

Examples:

Wastewater
Industrial process water
Aquaculture
Environmental monitoring

2. Communication Requirement

Common options:

RS485 Modbus
Analog output
IoT gateway

3. Additional Parameters

Many projects require multiple parameters.

Recommended combinations:

Wastewater

Aquaculture

pH
DO
Temperature
EC

Complete Online Water Quality Monitoring System

A professional water monitoring system includes:

Sensors

pH Sensor
ORP Sensor
DO Sensor
Conductivity Sensor
Turbidity Sensor

Data Acquisition

RTU
Data logger

Communication

4G
LoRaWAN
Ethernet

Platform

Functions:

Real-time dashboard
Historical analysis
Alarm notification
Remote management

Explore JW-IoT water monitoring products:

Water Quality Sensor Category

Request Online pH Monitoring Solution

Need an industrial pH monitoring system?

Send JW-IoT:

Water application
Required parameters
Installation environment
Communication requirements

Our engineering team will recommend a suitable solution.

Contact JW-IoT:

https://www.jw-iot.com/contact-us

FAQ

Q

1. What is an industrial online pH sensor?

A

An industrial online pH sensor is a fixed probe used to continuously measure the acidity or alkalinity of water. It can transmit pH and temperature data to a controller, PLC, RTU, data logger or cloud platform.
Q

2. What is the measuring range of the pH sensor?

A

The typical measuring range is 0 to 14 pH. The final range, accuracy and operating conditions should be confirmed according to the selected model and electrode.
Q

3. Does the sensor support RS485 Modbus RTU?

A

Yes. The industrial online pH sensor supports RS485 Modbus RTU for connection to PLCs, controllers, RTUs, data loggers, gateways and third-party monitoring systems.
Q

4. Can the sensor be connected to an IoT cloud platform?

A

Yes. The pH sensor can connect to an RTU or IoT gateway, which transmits data to a cloud platform through 4G LTE, LoRaWAN, Ethernet, Wi-Fi or another supported network.
Q

5. Is automatic temperature compensation included?

A

Yes. The sensor uses temperature measurement to compensate for the effect of temperature on electrode response and improve measurement stability.
Q

6. Can JW-IoT provide a complete online pH monitoring system?

A

Yes. JW-IoT can provide the pH probe, controller, RTU, gateway, solar power supply, monitoring cabinet, cloud dashboard and alarm configuration as a complete solution.
Q

7. How often should the pH sensor be calibrated?

A

The calibration interval depends on the water quality, required accuracy and amount of electrode contamination. Clean water may require less frequent calibration, while wastewater and high-fouling applications should be checked more often.
Q

8. Can the pH probe be installed directly in wastewater?

A

Yes, provided that the electrode material and operating conditions are suitable. The installation should avoid heavy sediment, direct mechanical impact and continuous accumulation of air bubbles.
Q

9. Can the sensor work with other water quality sensors?

A

Yes. It can be integrated with conductivity, ORP, dissolved oxygen, turbidity, temperature, ammonia nitrogen and other Modbus water quality sensors.
Q

10. Does JW-IoT support OEM or private-label projects?

A

Yes. JW-IoT supports OEM, white-label, customized cable length, communication configuration, gateway integration and cloud-platform deployment for distributors and system integrators.