Back to the Basics: LFL Analyzers and Control Systems

There are four main detector types used for combustible gas analyzers:

  1. catalytic
  2. infrared
  3. flame ionization
  4. flame temperature


Back to the Basics: Recipe Controls



Back to the Basics: Variable Ventilation


There are two main types: 

Back to the Basics: Elimination of “pockets” of high concentration

Places where pockets of high concentration might occur through uneven ventilation flow or obstruction by the product being coated should be sought out and eliminated. 

In general, the concentration immediately at the product being coated is very high, as the liquid solvent evaporates and only just begins to mix with air. 

Back to the Basics: Detection of Ventilation Loss

The minimum ventilation calculations should be made for the “worst case.” A direct measurement of the ventilation rate - using properly situated low-pressure switches - should be connected to the control logic so that the process shuts down immediately if ventilation falls below the minimum required.

In such cases the following shut down logic should be applied: