Faq; Q1: What Is Abc (Automatic Baseline Correction); Q2: Why I Need To Enable The Abc; Setting - ICP DAS USA CL-201-WF User Manual

8. FAQ

Q1: What is ABC (Automatic Baseline Correction)?

A1: ABC stands for the Automatic Baseline Correction which is used to adjust a shifted
baseline to the carbon dioxide level in fresh air. In case of normal indoor application,
the carbon dioxide level drops to nearly outside air where there are no human,
green plants or anything to elevate the carbon dioxide levels on weekday evenings
or weekends, the ABC algorithm constantly keeps track of the lowest reading and
slowly corrects it as the expected value in fresh air typically around 400 ppm.

Q2: Why I need to enable the ABC?

A2: When the CO2 concentration detected in a period time of unoccupied space is
greater than the base value of 400ppm, enable the ABC function to adjust the
baseline. Be careful that the ABC will not work if a space is constantly occupied
such as a hospital, 24-hr factory, 24-hr store, green house or other applications
where CO2 levels may be elevated at all times.
Q3: Does the CL-202/CL-212/CL-203/CL-213 enable the ABC as the factory default

setting?

A3: No, the ABC is default disabled in a CL-202/CL-212/CL-203/CL-213 logger to
prevent the baseline from being adjusted to an incorrect value in case of using in a
constantly occupied space.

Q4: What to do when the ABC is no work?

A4: When the ABC is no work regarding baseline correction, the
CL-202/CL-212/CL-203/CL-213 needs be returned to ICP DAS.
CL-200 Series User Manual Version 1.2.0 Apr. 2019 - 84 -