RS485 Modbus RTU Digital pH Sensor with IP68 Rating and Automatic Temperature Compensation for Online Water Quality Monitoring

The DPH790 digital pH sensor is a compact, fully digital electrode that adopts the classic glass electrode measuring principle for reliable, stable performance. Instead of a fragile analog signal, it outputs temperature-compensated pH values directly over RS485 Modbus, making it ideal for online monitoring and industrial control systems.

With a measuring range of 0.00~14.00 pH and 0.0~50.0 ℃, the sensor provides automatic temperature compensation and accuracy of 0.1% FS or ±0.02 pH (whichever is greater). Power and communication are electrically isolated inside the sensor, reducing noise and improving stability in electrically noisy plants. Calibration is performed with standard solutions using zero and slope calibration, with three calibration points at 4.01, 6.86 and 9.18 pH, the calibration point can be changed freely in daruifuno's controller. 

Housed in a rugged PPS body with IP68 protection, the DPH790 tolerates immersion, dust and humidity, and its 1″ NPT threads at both ends simplify mounting into pipes, tanks and flow cells. Communication follows standard Modbus RTU, so the electrode integrates directly with PLCs, controllers and SCADA systems.

1. Direct digital output: RS485 Modbus RTU sends temperature-compensated pH values straight to controllers. PLC, DTU or SCADA.
2. Electrical isolation: power and communication are isolated inside the sensor for low noise and high stability.
3. Automatic temperature compensation: built-in compensation keeps readings accurate from 0 to 50 ℃.
4. High accuracy: 0.1% FS or ±0.02 pH (whichever is greater) on a 0.00~14.00 pH range.
5. Rugged IP68 construction: PPS body rated for immersion, dust and humidity.
6. Simple installation: 1″ NPT threads at both ends suit pipes, tanks and flow cells; low 0.2 W power draw.
7. Full Modbus control: read measurements, change the slave address, calibrate and reset via standard function codes.

• Environmental protection and wastewater treatment
• Drinking water treatment and surface water monitoring
• Purified water and circulating water systems
• Electroplating, electronics and printing & dyeing
• Chemical, food and pharmaceutical processes
• Pollution source monitoring and industrial process control