PH Sensor Module with BNC Electrode Probe – High-Accuracy Liquid Quality Tester for Arduino, ESP32, and Hydroponics Automation Systems

Product Description The pH Sensor Module with BNC Electrode Probe is a precision analytical tool designed for real-time monitoring of liquid acidity and alkalinity. The kit consists of an industrial-grade pH electrode with a universal BNC connector and a signal conditioning board that converts the electrode's high-impedance millivolt signal into a stable analog voltage. This analog output (AO) can be directly read by the ADC of an Arduino, ESP32, or Raspberry Pi. Optimized for long-term reliability, it is the standard choice for hydroponics automation, aquarium water quality management, and chemical laboratory prototypes. The module features an on-board potentiometer for easy calibration against standard pH 4.0 or 7.0 buffer solutions.

Key Features

• Universal BNC Interface: Allows for quick connection and easy replacement of the pH electrode probe.

• On-board Calibration: Features a multi-turn potentiometer to calibrate the output voltage to match specific pH levels precisely.

• Wide Detection Range: Capable of measuring the full spectrum from pH 0 (Highly Acidic) to pH 14 (Highly Alkaline).

• Low Power Consumption: Operates efficiently at 5V with a very low current draw, ideal for continuous monitoring systems.

• Standard Analog Output: Provides a linear voltage signal proportional to the pH value, simplifying code implementation.

Technical Details

• Operating Principle: The electrode generates a voltage based on the hydrogen ion activity in the liquid, which the module amplifies and filters.

• Signal Conditioning IC: Utilizes high-precision op-amps to handle the extremely high impedance of the pH probe.

• Voltage-to-pH Mapping: Typically outputs approximately 2.5V at pH 7.0 (neutral), decreasing or increasing as the acidity/alkalinity changes.

• Response Speed: Achieves a stable reading within 1 minute, with a high sampling rate for rapid fluctuations.

• Probe Construction: The glass electrode is protected by a durable plastic housing, suitable for varied liquid types.

• Reference System: Features a non-refillable Ag/AgCl reference system for maintenance-free operation during its lifecycle.

• Gain Adjustment: Integrated trimmer allows for the adjustment of the signal gain to maximize resolution for specific microcontrollers.

• Temperature Compensation: While calibrated for 25°C, the module maintains high stability across a 0-60°C range.

• Interface Pins: Standard 3-pin interface: VCC (5V), GND (Ground), and AO (Analog Output).

• Power Stability: Features on-board filter capacitors to minimize noise from the power supply affecting the sensitive analog signal.

• LED Feedback: A bright on-board power LED provides immediate confirmation of the module's operational state.

• Mounting Design: The PCB includes four M3 mounting holes for secure attachment to enclosures.

• Electrode Storage: The probe comes with a protective cap containing KCL storage solution to keep the bulb hydrated.

• Chemical Resistance: The probe body is resistant to most common household and agricultural chemicals.

• Logic Compatibility: Output is 0-5V; for 3.3V systems like ESP32, a simple voltage divider or logic level shifting is recommended.