Siemens CP 1243-8 IRC, Руководство по эксплуатации

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Configuration and operation
4.7 Configuration in STEP 7 Basic
CP 1243-8 IRC
Operating Instructions, 06/2015, C79000-G8976-C385-01
83
Set limit value 'low' / Set limit value 'high'
Requirements for the function
● Configuration of the threshold trigger for this data point
● PLC tag in the bit memory operand area or data area
The analog value data point must be linked to a PLC tag in the bit memory or data area
(data block). For PLC tags of hardware modules (input operand area) limit value
configuration is not possible.
The configuration of limit values is pointless for measured values that have already been
preprocessed on the CPU.
Function
In these two input boxes, you can set a limit value in the direction of the start of the
measuring range or in the direction of the end of the measuring range. You can also
evaluate the limit values, for example as the start or end of the measuring range.
Configuration of the limit value
The limit value is configured as a whole decimal number. The range of values is based on
the range of values of the raw value of analog input modules.
Range Raw value (16 bits) of the PLC tag Module output [mA] Measuring
range [%]
Decimal Hexadecimal 0 .. 20
(unipolar)
-20 .. +20
(bipolar)
4 .. 20
(life zero)
Overflow 32767 7FFF > 23.515 > 23.515 > 22.810 > 117.593
Overrange 32511
...
27649
7EFF
...
6C01
23.515
...
20.001
23.515
...
20.001
22.810
...
20.001
117.593
...
100.004
Nominal range
(unipolar / life zero)
27648
...
0
6C00
...
0000
20
...
0
20
...
4
100
...
0
Nominal range (bipolar) 27648
...
0
...
-27648
6C00
...
0000
....
9400
20
...
0
...
-20
100
...
0
...
-100
Underrange
(unipolar / life zero)
-1
...
-4864
FFFF
...
ED00
-0.001
...
-3.518
3.999
...
1.185
-0.004
...
-17.59
Underrange (bipolar) -27649
...
-32512
93FF
...
8100
-20.001
...
-23.516
-100.004
...
-117.593
Undershoot / wire break -32768 8000 < -3.518 < 1.185 < -17.593