Start and end p/v are not calculated in Empower 3 - WKB12728

SYMPTOMS

• Start p/v and end p/v are not being calculated in Empower 3

ENVIRONMENT

• Empower 3

CAUSE

The baseline is flat at 0.

FIX or WORKAROUND

Three things are necessary for calculation of start and end p/v:

1. System Suitability must be enabled for the project.
2. Either European or All must be selected for the Pharmacopeia type.
3. The baseline at the start or end of the peak must not be 0.

The following formula is used to calculate the p/v value:

Start p/v = (height / height start)

End p/v = (height / height end)

height = height of the peak

height start = valley height at the start of the peak

height end = valley height at the end of the peak

Based on this formula, if the baseline/height start/height end is 0, then the denominator in the formula is 0, which cannot be. Consequently, you do not get a value for p/v. 

ADDITIONAL INFORMATION

Enable Calculate Detector Noise and Drift in the Noise and Drift tab of the processing method.