Which specification is the maximum increment for the AFM indicator?

Which specification is the maximum increment for the AFM indicator?

• A. No greater than 8 CFM
• B. No greater than 12 CFM
• C. No greater than 15 CFM
• D. No greater than 10 CFM

Answer: (D)

Think of the AFM indicator’s specification as its reading resolution—the smallest, reliable change it can display as airflow is adjusted. “No greater than 10 CFM” means the indicator should not jump by more than 10 cubic feet per minute in a single step; readings change in steps of 10 CFM or smaller. This level of precision is essential for accurate calibration and diagnostics, ensuring gradual changes are tracked without skipping over smaller fluctuations. A tighter limit like 8 CFM would be more restrictive than necessary, while 12 CFM or 15 CFM would allow larger jumps and reduce resolution. Therefore, the maximum allowed increment is 10 CFM.

Think of the AFM indicator’s specification as its reading resolution—the smallest, reliable change it can display as airflow is adjusted. “No greater than 10 CFM” means the indicator should not jump by more than 10 cubic feet per minute in a single step; readings change in steps of 10 CFM or smaller. This level of precision is essential for accurate calibration and diagnostics, ensuring gradual changes are tracked without skipping over smaller fluctuations.

A tighter limit like 8 CFM would be more restrictive than necessary, while 12 CFM or 15 CFM would allow larger jumps and reduce resolution. Therefore, the maximum allowed increment is 10 CFM.