General
Refillable

The Chauvin Arnoux BR42-BA4 is a calomel reference electrode developed specifically for pH and redox measurements in laboratory and field applications. It serves as a reference electrode in combination with separate measuring electrodes, providing a constant reference potential required for the correct conversion of the measured voltage into a pH value or redox value. The electrode features a glass body and a porous ceramic diaphragm that allows the reference electrolyte to exit in a controlled manner, preventing uncontrolled leakage. The reference electrode is filled with a saturated potassium chloride solution (KCl, 3 mol/L), ensuring high stability and a low temperature coefficient. Connection is made via a 4 mm banana plug, compatible with corresponding measuring instruments and measuring electrodes.

Applications

The BR42-BA4 is suitable for a wide range of applications, particularly in chemical analysis, the food industry, and environmental protection. It is used in combination with measuring electrodes such as BV41H or XV41 to perform precise pH and redox measurements. The electrode is especially suitable when high long-term stability and a reliable reference potential are required. Due to the use of chloride ions in the electrolyte, it is not suitable for applications where Ag⁺ ions or other substances are present that may react with chloride ions and form a precipitate. In such cases, a reference electrode based on mercury sulfate is recommended.

Functions and Equipment in Detail

The reference electrode is based on the calomel system (Hg/Hg₂Cl₂), known as a saturated calomel electrode (SCE). Inside the glass body, there is a drop of mercury and a drop of mercury chloride (calomel) on a platinum wire, which is immersed in the saturated KCl solution. The porous ceramic diaphragm enables controlled exchange between the electrolyte solution and the sample solution, ensuring stable contact. The electrode is refillable, allowing the electrolyte to be renewed as needed to maintain measurement accuracy.

Technology Explained Simply

In pH measurements, the potential difference between the measuring electrode (which responds to hydrogen ions) and the reference electrode (which provides a constant potential) is measured. The measuring device converts this difference into a pH value. The BR42-BA4 ensures that the reference potential remains stable over a long period, which is crucial for reproducible measurement results. The 4 mm banana plug enables easy and secure connection to measuring instruments and measuring electrodes that support this connection. The operating temperature ranges from 0 to 80 °C, allowing use in a wide range of environments.

Compatibility and Accessories

The BR42-BA4 is to be used in combination with measuring electrodes such as BV41H or XV41. Suitable accessories include the KCl 3 mol/L solution (30 mL) and the pepsin/HCl solution (125 mL), which are suitable for maintenance and calibration of the electrode. These accessory items support electrode care and help maintain measurement accuracy over time.

Installation and Mounting

The electrode is immersed directly into the sample solution, with the glass body and diaphragm fully submerged in the liquid. Connection is made via the 4 mm banana plug to the measuring device. It is important to thoroughly clean the electrode before use and, if necessary, refill it with fresh electrolyte to avoid measurement errors. The electrode is not designed for use with aggressive chemicals or under high pressure.

Operational Advantages

The BR42-BA4 offers high long-term stability and a low temperature coefficient, resulting in reliable and reproducible measurement results. The use of a ceramic diaphragm ensures controlled exchange between the electrolyte and sample solution, extending the electrode’s service life. The refillable electrolyte allows for maintenance that secures accuracy over an extended period. The combination with suitable measuring electrodes and accessories enables flexible application in various industries.