This product is a reference salt for field calibration of thermo-hygrometers, specifically developed for devices such as the C.A 1246 model by Chauvin Arnoux. It serves as a precise calibration method to ensure the measurement accuracy of humidity measuring devices. The reference salt is calibrated to a relative humidity of 75 %, enabling a reproducible and reliable verification of device display under real operating conditions. Calibration is performed by exposing the measuring device in a closed space with the salt cartridge, thereby creating a constant humidity environment used for adjustment.

Applications
This accessory is primarily intended for the maintenance and calibration of thermo-hygrometers in industrial, technical, or laboratory applications. It is used to check the accuracy of relative humidity measurement, particularly in environments where precise humidity control is required, such as in the food industry, pharmaceuticals, or air conditioning systems. Regular calibration with the reference salt helps detect measurement deviations early and ensures long-term stability of the devices.

Functions and Equipment in Detail
The salt cartridge generates a defined, stable relative humidity of 75 %, achieved through the physical properties of the salt used. This humidity is independent of external environmental conditions, as long as the cartridge is placed in a closed container or suitable chamber. The reference salt is thus a passive calibration standard that requires no external power or additional equipment. It is specifically designed for use with the C.A 1246 thermo-hygrometer, with the application method described in the device documentation.

Technology Explained Simply
The functionality is based on the so-called saturation vapor pressure property of certain salts. At a specific temperature and under closed conditions, an equilibrium is established between the salt and the surrounding air, creating a constant relative humidity. The reference salt for 75 % r.H. (relative humidity) utilizes this physical property to create a reproducible measurement environment. Calibration is performed by placing the thermo-hygrometer near the cartridge, allowing the device to compare the displayed humidity with the known value of 75 %. Deviations can then be corrected to restore accuracy.

Compatibility and Accessories
The accessory is specifically developed for the thermo-hygrometer model C.A 1246. It is not intended for other devices unless manufacturer specifications confirm compatibility. Use with other models is not guaranteed and may lead to inaccurate results. This is a pure calibration accessory and does not include any additional functions or devices. Calibration is performed exclusively by exposing the device near the salt cartridge.

Mounting and Installation
Mounting or installation is not required. The salt cartridge is simply placed in a closed container, with the thermo-hygrometer positioned nearby to measure humidity. The exact procedure is described in the C.A 1246 user manual. It is important to store the cartridge dry and clean to maintain calibration accuracy. The cartridge should not come into contact with water or other liquids.

Operational Advantages
The use of the reference salt enables quick, cost-effective, and reliable field calibration without the need for complex laboratory equipment. Calibration can be performed directly at the site of use, saving time and logistics costs. The stability of the 75 % relative humidity ensures consistent results, guaranteeing the reliability of measuring devices over extended periods. The simple handling makes the accessory suitable even for technical personnel without specialized calibration experience.