Water Quality pH Sensor, 0~14pH, RS485 (Modbus RTU)

The pH electrode relies on a sensitive glass membrane and internal reference solution for potential measurement. Prolonged drying can cause slow response, increased drift, or even failure. Therefore, the electrode must be immersed in a specialized storage solution (such as KCl solution) when not in use. Do not use pure water or distilled water, as this will dilute the reference solution and shorten its lifespan. Maintaining moisture preserves electrode activity, ensuring rapid response and stable output. This is a critical step for sustaining long-term reliability of pH sensors.

Most standard pH sensors operate within 0–50°C and are suitable for general water applications like drinking water, surface water, and industrial circulating water. For high-temperature, strong acid/alkali, or organic solvent-containing water, specialized high-temperature electrodes or corrosion-resistant industrial electrodes are required. Operating sensors beyond their rated temperature or pressure limits can cause damage to the sensing membrane, reference electrolyte leakage, or unstable output. Therefore, sensor selection must be based on actual operating conditions.

When pH values drift, fluctuate significantly, or exhibit slow response, follow these troubleshooting steps: First, inspect the electrode for cleanliness—contaminants or oil films can impair the sensing membrane's contact with the water sample. Next, verify that cable connections are secure and power supply is normal. Then determine if recalibration is required. If the pH electrode has been in use for over a year or stored improperly, replacement may be necessary. Additionally, environmental noise and strong electromagnetic interference can affect signals, so ensure proper grounding and shielding conditions.