The CWD device series (Calorimetry, Wobbe Index and Specific Density) comprises variants of combustion calorimeters for the direct and continuous determination of gas quality from the following measured and calculated variables:

– Wobbe-lndex
– Specific density
– Heating and calorific value
– Combustion Air Requirement (CARI) and air requirement, with integrated gas analysis
– Energy quantity, with the extended EMS system.

The heating value and calorific value are calculated from the measured values of Wobbe index and specific density. If the CWD is extended with components for gas analysis, the measured gas composition can also be used to determine the air requirement or CARI.

Due to its functional principle, the CWD detects the entirety of all combustible gas components, which also allows it to be used for gases with rapidly changing gas compositions.