pH Value Detection Sensor Module Waterproof Digital Probe Kit with Dual Temperature Compensation Function for pH Value Monitoring and Control.

Specifications: Item Type: pH Detection Sensor Heating Voltage: 5 ± 0.2 V (AC/DC) Operating Current: 5-10 mA Detectable Concentration Range: pH 0-14 Detection Temperature Range: 0-100 ℃ Response Time: ≤5S Stability Time: ≤60S Component Power Consumption: ≤0.5 W Operating Temperature: -10 ~ 50 ℃ (Rated Temperature 20 ℃) Operating Humidity: 95% RH (Rated Humidity 65% RH) Terminal: BNC connector

Package List: 1 x pH Value Sensor Module 1 x Digital Probe

Note: 1. The probe cannot be tested continuously for extended periods. 2. If using a particulate product such as Photon or Argon, be aware of potential errors.

This is a hardware issue related to fluctuating voltage at the analog port, enough to cause your pH reading to fluctuate by 0.7 or more at these low voltage readings. To resolve this, you will need to add a 0.1 µF capacitor between the analog port you are using and ground.