GFK-1504N
Chapter 10 Analog Input Modules
10-23
10
IC200ALG260
Analog Input Module, 12 Bit Voltage/Current 8 Channels
Count and Input Voltage
Voltage
12
10
8
6
4
2
0
-2
-4
-6
-8
-10
-12
0 8192 16384 24576 32767
Unipolar
-32768 -16384 0 +16383 +32767
Bipolar
Count
Unipolar
Bipolar
2.5mV
5.0mV
24
16
8
0
0V
7.5mV
2.5mV = 8 counts
5.1225V
5.125V
16408
16400
16392
16384
5.12V
5.1275V
2.5mV = 8 counts
The following equations can be used to calculate counts values:
Bipolar voltage:
Counts = ( +Voltage In) x (3200)
Unipolar voltage:
Counts = ( +Voltage In) x (3200)
For a change in the reported count value to be seen, input voltage must be
increased by at least 2.5mV. If the module receives an increase less than
2.5mV, the previous count value is still reported. For example:
Voltage
Count
5.1200V
16384
5.1220V
16384
5.1225V
16392