Lenze PLC Designer PLC Designer (R2-x) - Manual (Page 671)

L-force | PLC Designer
PLC Designer Libraries
DMS 3.2 EN 02/2011 TD29 669
When ENABLE is reset to FALSE, output OUT will not be changed, i.e. no further pulse
will be generated. If you explicitly also want to get OUT FALSE when ENABLE is reset to
FALSE, you might use "OUT AND ENABLE" (i.e. adding an AND box with parameter
ENABLE) at the output.
Example in CFC:
FREQ_MEASURE
Provided by util.lib.
This function block measures the (average) frequency (Hz) of a boolean input signal.
You can specify over how many periods it should be averaged. A period is the time
between two rising edges of the input signal.
Input variables:
Variable Data type Description
IN BOOL Input signal
PERIODS INT Number of periods, i.e. the time intervals between the rising edges, over
which the average frequency of the input signal should be calculated.
Possible values: 1 to 10
RESET BOOL Reset of all parameters to 0
Output variables:
Variable Data type Description
OUT REAL resulting frequency in [Hz]
VALID BOOL FALSE until the first measure has been finished, or if the period > 3*OUT
(indicating something wrong with the inputs)