APX1 - G2 pH ORP Controller For Power Plant & Pure Water

The APX1 - G2 online pH ORP Controller, developed and produced by Delfino, is a specialized solution tailored for power plants and pure water applications. Equipped with the ASP500N grounded pH electrode, it is designed to excel in the challenging pH measurement environments of power plants.

In power plant settings, pH sensors often face numerous issues, particularly when measuring pure water such as condensation water and feed water. These waters have extremely low conductivity, typically ranging between 2uS/cm and 10uS/cm, resulting in very high resistance. The purity of the water poses significant difficulties for accurate measurement.

To prevent metal corrosion in the water vapor system of power plants, strict control of the water vapor's pH value is essential. The APX1 - G2 pH controller and PH Sensor are required in various systems within power plants, including the steam and water sampling system, boiler feed water system, condensate polishing system, sewage and wastewater treatment system, gray water treatment system, desulfurization system, circulating water system, and internal cooling water system - anywhere water and steam are present.

How to Solve the Impact of Pure Water on pH Measurement?

• Check the airtightness of the water sample circulation pipeline. Add PTFE gaskets to the joints to ensure there are no pinholes in the pipeline, preventing the absorption of CO2.
• Select a pH electrode with pure water measurement characteristics. The measurement electrode should preferably have a low-resistance glass membrane, and the reference electrode should have a large liquid junction area, good salt bridge solution penetration, a stable liquid junction potential, and be resistant to clogging.
• Prioritize the use of stainless steel Flow cells and ensure proper grounding to reduce the influence of flowing potential.
• Strictly control the flow rate at the instrument's inlet. Maintain a constant low flow rate measurement to avoid fluctuations in pH measurement values caused by drastic changes in flow rate.
• Frequently replace or clean the fiber filter element of the instrument's inlet filter to prevent iron and copper oxides from contaminating the electrode.
• Regularly clean and maintain the pH electrode. For grease contamination, clean it with a neutral detergent. For metal ion contamination of Cu and Fe, clean it with 10% dilute hydrochloric acid. After cleaning, immediately rinse it with demineralized water and soak it for 24 hours to restore its performance.
• The water vapor control indicators use 25°C as the base temperature. The temperature compensation of the pH controller cannot correct the pH temperature change of the solution. Therefore, controlling the temperature of the constant temperature water tank at 25°C can reduce the temperature effect.

Features of APX1 - G2 Online pH Meter

• Supports pH electrode connected to solution ground to eliminate electrostatic interference in water.
• In addition to automatic or manual temperature compensation, a 25°C conversion function is included.
• For more accurate pH measurement, a 5-point calibration is added to the standard 3-point calibration.
• 2 settable SPST relays, 2 channels of 4-20mA current output, and 1 RS485 interface.

Specification

We offer the ASP500 pH electrode with solution grounding for the pH controller meter, which provides fast response and stable measurement. Additionally, we provide stainless steel flow cells. Delfino has been dedicated to the R&D and production of water quality analysis instruments for over a decade. Our main products include pH ORP analyzers, conductivity analyzers, turbidity analyzers, COD analyzers, dissolved oxygen analyzers, ammonium analyzers, chlorine analyzers, and more. If you are interested in our products, please don't hesitate to contact us.