General
Refillable	ja -

The Chauvin Arnoux BR42-BA2 is a calomel reference electrode, specifically designed for pH and redox measurements in laboratory and field applications. It serves as a reference electrode in systems with separate electrodes, providing a constant and stable potential during measurement. The electrode consists of a glass body filled with a saturated potassium chloride solution (3 mol/l) and features a porous ceramic diaphragm that controls electrolyte flow, preventing uncontrolled leakage. The reference electrode is equipped with a 2 mm banana plug, enabling compatible connection to measuring instruments and measuring electrodes.

Applications

The BR42-BA2 is suitable for a wide range of applications in pH and redox measurement, particularly in laboratories, the food industry, and scientific research. It is used in combination with measuring electrodes such as BV41H or XV41 to achieve precise measurement results. The electrode is not suitable for applications where chloride ions react with components of the measuring solution, for example with silver ions (Ag⁺), as this may lead to AgCl precipitation. In such cases, a reference electrode based on mercury sulfate is preferable.

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. The saturated KCl solution serves as the reference electrolyte, ensuring long-term stability and a low temperature coefficient. The ceramic diaphragm ensures controlled diffusion of the electrolyte and prevents uncontrolled leakage.

Technology Explained Simply

In pH measurements, the potential difference between the measuring electrode (which reacts to hydronium ions) and the reference electrode (which provides a constant potential) is recorded. The measuring device converts this difference into a pH value. The BR42-BA2 provides the stable reference potential necessary for accurate measurement. The electrode is refillable, allowing maintenance and replacement of the electrolyte to maintain performance over a longer period.

Compatibility and Accessories

The BR42-BA2 is specifically designed for use with measuring electrodes of type BV41H or XV41. Available accessories include solutions such as KCL 3mol/L (30 mL) and Pepsin/HCl (125 mL), which can be used for calibration and maintenance of the electrode. Connection is made via the 2 mm banana plug, which is compatible with a wide range of measuring instruments and connection variants.

Mounting and Installation

The electrode is immersed directly into the measuring solution, ensuring that the glass body and diaphragm are fully covered. Connection to the measuring device is made via the 2 mm banana plug. Regular maintenance, including refilling of the reference electrolyte, is recommended to ensure accuracy and extend the electrode’s service life.

Operational Advantages

The BR42-BA2 offers high stability and reliability for pH and redox measurements. The use of a ceramic diaphragm and saturated KCl solution ensures a long service life and minimizes the need for frequent maintenance. The electrode is easy to handle and particularly suitable for applications requiring a clear separation between measuring and reference electrodes, for example in educational settings or when the electrodes have different lifespans.