Main

VDVL - APMonitor Option

 Type: Floating Point, Input
 Default Value: 1.0e20
 Description: Delta validity limit

VDVL is the maximum change of a measured value before it is considered an unrealistic change. The change in measured values is recorded at every cycle of the application and compared to the VDVL limit. Validity limits are placed to catch instrument errors that may otherwise create bad inputs to the application. If a delta validity limit is exceeded, the action is to either freeze the measured value at the last good value (VLACTION=0) or change the measured value by a maximum of VDVL in the direction of the bad measurement (VLACTION=1). Another way to minimize the impact of unrealistic changes in measurements is to set FSTATUS between 0 and 1 with values closer to 0 becoming insensitive to measurement changes.

See also VLACTION, VLHI, VLLO