N32O
User's manual
25
Figure 11 shows how the filter works, where the InS signal is a disturbed input signal, while
the InF signal is the signal after passing the filter, and tL and tH are the filter settings. The
signal levels with the times shorter than the filter settings are ignored and do not change
the state of the filtered signal. The testing of the pulse duration is done each time after the
state change at the meter input.
A different filtering method was used in the fast change pulse counter mode. Filtering in
this case is based on triggering a counter to count down at each edge of the input signal.
The setting of the enabled counter corresponds to the set minimum pulse duration. When
the counter counts up to 0, and there has been no change of the input status during this
period, the given level is considered as correct. In this case, the change of the filtered
signal happens each time the counter counts down to 0, and the pulse counting occurs
when the filtered signal changes from inactive to active.
During the measurements, the main measuring value in the main and the additional
channels may be changed by a number of mathematical operations e.g. averaging,
dividing or multiplication by a constant, conversion by the mathematical functions and by
the individual characteristics. The sequence of operations is shown in Figure 12. Not all
the conversion functions are available for every type of the measurement (see the table
above) and the main displayed value can be changed to another measuring value (
dVAL
parameter from the
dISPL
menu). For simplicity, the figure shows only one measuring
channel and the alarms and the analog output control of the real time clock has been
omitted.
Fig. 11: Graphical example of the signal filtering.