GFK-1504K Chapter 12 Analog Mixed I/O Modules 12-7
12
IC200ALG430
Analog Mixed Module, 12 Bit Input Current 4 Channels and
Output Current 2 Channels
Scaling
The following graphs show the relationship between the input current measured at the field
terminals and the data values for the module.
Count vs Input Current
12.202mA
0 8192 16384 24576 32767
Count
24
20
16
12
8
4
0
mA
12.194mA
12.198mA
16408
16400
16392
16384
12.19mA
8 counts =
4µA
The following equation can be used to calculate counts values:
Counts = ( Current in mA - 4mA) x (32768 / 16.38mA
)
For a change to be seen in the reported count value, input current must be increased by at
least 4µA. If the module receives an increase less than 4µA, the previous count value is
still reported. For example:
Current Count
12.190mA 16384
12.192mA 16384
12.194mA 16392