Transmitter
The Instrava pH / ORP sensor is designed for continuous, reliable measurement of acidity, alkalinity, and oxidation-reduction potential in industrial and environmental applications.
Built for long-term stability, the sensor integrates high-accuracy electrodes with digital RS485 (Modbus RTU) communication, ensuring strong anti-interference performance and seamless integration with PLC, DCS, and water quality analyzers.
It is widely used in water treatment, chemical processing, power generation, food & beverage, and environmental monitoring, where stable pH and ORP control is critical to process safety and efficiency.
Transmitters & Sensors Description
pH / ORP Sensor Key Features
High-precision pH & ORP measurement
Accurate monitoring across a wide pH and ORP range for demanding industrial processes.
Digital RS485 Modbus RTU output
Stable long-distance transmission with no signal drift, ideal for harsh electrical environments.
Industrial-grade electrode design
Fast response, strong resistance to contamination, and long service life.
Low maintenance with optional automatic cleaning
Reduces manual intervention in wastewater and chemical applications.
Wide compatibility
Fully compatible with Instrava multifunction water quality analyzers and third-party control systems.
pH/ORP Sensor Applications
Industrial water and wastewater treatment
Chemical and petrochemical processes
Power plant water systems
Environmental water monitoring
Food and beverage process water
General industrial online pH and ORP measurement
pH ORP Sensor Measurement Principle
The pH sensor measures hydrogen ion activity using a glass electrode and reference electrode.
The potential difference generated between the electrodes varies proportionally with the pH value of the solution.
ORP measurement is based on detecting the oxidation or reduction potential of the solution.
The sensor outputs a millivolt (mV) signal representing the solution’s ability to gain or lose electrons.
Both signals are digitally processed and transmitted via RS485 for stable and accurate readings.
pH ORP Sensor Installation & Integration
Immersion, pipeline, or flow-cell installation
Plug-and-play with Instrava water quality analyzers
Compatible with PLC, SCADA, and DCS systems
Suitable for continuous online monitoring
Transmitters & Sensors Parameter
| Parameter | pH Sensor | ORP Sensor |
|---|---|---|
| Measurement Range | 0 ~ 14 pH | -1999 mV ~ +1999 mV |
| Operating Temperature | 0 ~ 80 ℃ | -10 ~ 100 ℃ |
| Operating Pressure | ≤ 0.6 MPa | ≤ 0.8 MPa |
| Measurement Accuracy | pH: ±0.05 pH Temperature: ±0.5 ℃ | ORP: ±1 mV Temperature: ±0.5 ℃ |
| Temperature Sensor | NTC 2.252K | NTC 2.252K |
| Wetted Material | ABS, Glass | ABS, Glass |
| Protection Class | IP65 | IP65 |
| Sensor Dimensions | Ø26.7 × 160 mm Ø12 × 120 mm | Ø26.7 × 160 mm Ø12 × 120 mm |
| Process Connection | 3/4″ NPT, PG13.5 | 3/4″ NPT, PG13.5 |
| Signal Cable Length | 5 m standard Up to 20 m customizable | 5 m standard Up to 20 m customizable |
Instrava OEM/ODM
Electrode material selection for specific chemical environments
Cable length and mounting accessories customization
Modbus register optimization for system integration
Calibration guidance and long-term maintenance support
Instrava focuses on stable field performance, not just laboratory accuracy.
Under normal industrial water conditions, the typical service life of a pH or ORP electrode is 12–18 months. Actual lifespan depends on water quality, temperature, chemical composition, and maintenance practices.
For stable industrial water, calibration is usually recommended once per month. In harsh or fluctuating process conditions, more frequent calibration (every 1–2 weeks) helps maintain measurement accuracy.
Electrode lifespan can be shortened by high temperature, strong acids or alkalis, oil contamination, solids abrasion, and improper cleaning. Regular inspection and correct cleaning procedures significantly extend sensor life.
Yes. The sensor is suitable for wastewater applications; however, regular cleaning is recommended to prevent fouling on the glass membrane, which may affect response time and accuracy.
The pH ORP sensor is compatible with most standard industrial pH/ORP transmitters and analyzers that support glass electrode inputs and NTC temperature compensation.
Stable long-term operation is achieved through proper installation, correct calibration, regular cleaning, and suitable electrode selection based on process conditions. Using compatible transmitters with temperature compensation further improves measurement stability.
By choosing Instrava, you gain a partner with a deep understanding of industrial applications and the expertise to meet today’s operational challenges.
Our role extends beyond products—we support your success through dependable solutions and long-term commitment.
Innovation at Instrava is guided by real industrial requirements. We continuously refine our technologies to address evolving operational challenges, ensuring practical and reliable performance in demanding environments.
We provide engineering-level customization to match specific process conditions. From measurement range and materials to output signals and installation options, our solutions are configured to fit real applications.
Quality and reliability are fundamental to every Instrava product. Manufactured under strict quality control and thoroughly tested, our instruments deliver accurate, stable, and long-term performance.
Instrava combines global engineering expertise with responsive local support, ensuring our partners benefit from internationally aligned technology and timely regional service.
Our broad portfolio of measurement and control instruments enables us to address a wide range of industrial needs, providing integrated solutions from a single, reliable source.
We work closely with our partners from technical consultation to after-sales support. Our focus is on delivering solutions that create lasting value and support long-term operational success.
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