Firmware: V2.18 / V--
26.10.2022
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6.2.4 Marker $LDSW, $ARC, $ARCNR - LDSWin visualisation
For the
LDSWin visualisation
, the three markers will be used to determine whether the process variables will be
displayed in LDSWin and their value histories archived or not.
Marker
Possible values
Note
$LDSW
R
: read-only (actual values)
W
: for reading and writing (setpoints)
X
: No visualisation
Visualisation in LDSWin
$ARC
X
: for archiving
The archiving takes place in a time grid of 2 minutes over one week.
$ARCNR
-
The archive number is calculated automatically and
must not be entered
manually
!
6.2.5 Marker $FTYP, $FTZ, $FN - Probes and sensors
It is possible to use the
Signal List
to automatically generate the function blocks for converting the analogue
input values into the physical values. The generated CODESYS export file contains the variable declaration
All_Sensors
in
Resources → Global Variables → GLT Process
as well as the function block definition
All_Sensors
. The function block is instantiated in PLC_PRG and called before the control routines are called.
The following columns are used for this:
$FTYP
: Type of the sensor
PT1000
creates a Pt1000_T instance for the Pt1000 inputs of the controller
Sensor 20 mA
creates a SENSOR_T instance for sensors with current interface 4..20 mA
Sensor 10 V
creates a SENSOR_T instance for sensors with voltage interface 0..10 V
$FTZ
and
$FN
: Parameters of an optional PTn link connected downstream of the characteristic curve block e.g.
for averaging
$MIN
and
$MAX
: Measuring range of the sensor with current / voltage interface (is ignored for Pt1000)
$M
and
$B
: Gradient and Y-axis intercept of the linear equation - are calculated automatically.
The name of the instance of the characteristic curve block is derived from the identifier of the input ($EA2). The
prefix
E_
of the input variables is replaced with the prefix
F_
.
The row of the Excel worksheet shown above results in the following program code in CODESYS:
Resources → Global Variables → Process → All_Sensors
VAR_GLOBAL CONSTANT
...
(* 42 *) F_T_ZULUFT : SENSOR_PT1000_T;
...
END_VAR
