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L-force | plc designer – Lenze PLC Designer PLC Designer (R2-x) User Manual

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L-force | PLC Designer

PLC Designer Libraries

672

DMS 3.2 EN 02/2011 TD29

Example in ST:

First of all ARRAY P must be defined in the header:

VAR

...

CHARACTERISTIC_LINE:CHARCURVE;

KL:ARRAY[0..10] OF POINT:=(X:=0,Y:=0),(X:=250,Y:=50),

(X:=500,Y:=150),(X:=750,Y:=400),7((X:=1000,Y:=1000));

COUNTER:INT;

...

END_VAR

Then we supply CHARCURVE with for example a constantly increasing value:

COUNTER:=COUNTER+10;

CHARACTERISTIC_LINE(IN:=COUNTER,N:=5,P:=KL);

The subsequent tracing illustrates the effect:

RAMP_INT

Provided by util.lib.

RAMP_INT serves to limit the ascendance or descendance of the function being fed:

The input consists on the one hand out of three INT values: IN, the function input, and
ASCEND and DESCEND, the maximum increase or decrease for a given time interval,
which is defined by TIMEBASE of the type TIME. Setting RESET to TRUE causes
RAMP_INT to be initialised anew.

The output OUT of the type INT contains the ascend and descend limited function
value.

When TIMEBASE is set to t#0s, ASCEND and DESCEND are not related to the time
interval, but remain the same.