The BR43-S7 is a reference electrode of the mercury sulfate (Hg/Hg2SO4) type, manufactured by Chauvin Arnoux, and serves as a reference electrode for measurements of redox potential (ORP) and pH value in systems with separate electrodes. It is used in combination with a measuring electrode (e.g. BAG1 or XAG1) to enable precise potential difference measurement. The electrode features a glass body and a porous ceramic diaphragm that controls the release of the reference electrolyte (saturated potassium sulfate solution, K2SO4), preventing uncontrolled leakage. The reference element consists of a drop of mercury and a drop of mercury sulfate on a platinum wire, ensuring a constant and stable potential during measurement.

Applications
The BR43-S7 is particularly used in argentometric dosing applications, where the use of a calomel electrode is not possible, as Ag+ ions react with chloride ions and may precipitate silver chloride (AgCl). The choice of reference electrode depends on specific experimental conditions. It is suitable for potentiometric measurements requiring high stability of the reference potential and is frequently used in laboratory and field applications where measurement accuracy is critical.

Functions and Equipment in Detail
The electrode is equipped with an S7 connector, enabling a secure and standardized connection to compatible measuring instruments. The glass body protects sensitive internal components and ensures high chemical resistance. The ceramic diaphragm ensures controlled diffusion of the electrolyte, guaranteeing uniform and reproducible measurements. The saturated potassium sulfate solution as reference electrolyte offers high stability and is suitable for a wide range of applications.

Technology Explained Simply
In pH and redox measurements, the potential difference between the measuring electrode and the reference electrode is measured. The reference electrode provides a constant comparison potential that remains independent of measurement conditions. The BR43-S7 achieves this through the combination of mercury, mercury sulfate, and the saturated potassium sulfate electrolyte. The porous ceramic diaphragm regulates the exchange of electrolyte with the sample solution, enabling stable and reproducible measurements. The electrode is designed for operating temperatures from 0 to 80 °C, making it suitable for a wide range of laboratory and industrial applications.

Compatibility and Accessories
The BR43-S7 is specifically designed for use with measuring electrodes such as BAG1 or XAG1. Compatible accessories available in the range include a Pepsin/HCl solution (125 ml), which can be used for maintenance or calibration of electrodes. The electrode is equipped with an S7 connector, enabling direct connection to devices with a corresponding socket.

Mounting and Installation
Mounting is done by screwing the S7 connector to the measuring device. The electrode is immersed in the sample solution, ensuring the tip is fully covered. The ceramic tip must be clean and free of deposits to ensure accurate measurement. Prior to first use or after prolonged storage, electrode preparation is required, as described in the datasheet. The cable length is 1 meter, providing sufficient reach for use in laboratory and field environments.

Advantages in Operation
The BR43-S7 offers high stability of the reference potential, which is essential for precise and reproducible measurements. The use of mercury sulfate instead of calomel prevents the formation of silver chloride in the presence of chloride ions, making the electrode indispensable for certain chemical applications. The ceramic tip ensures controlled diffusion of the electrolyte, extending the electrode's service life. The electrode is designed for use in laboratory and field environments and is particularly suitable for applications requiring high measurement accuracy and stability.