GE VersaMax IC200PWR002 - Page 360

GFK-1504N Chapter 10 Analog Input Modules 10-45
10
IC200ALG264, IC200ALG266
Analog Input Module, 15 Bit Current 15 Channels
Scaling
The following graphs illustrate the relationship between the input current
measured at the field terminals and the data that is output by the module.
Count and 4-20mA Input Current
12.1935mA
0 8192 16384 24576 32767
Count
24
20
16
12
8
4
0
mA
12.1925mA
12.193mA
16386
16385
16384
12.192mA
0.5µA = 1counts
10.241875mA
10.240625mA
10.24125mA
16386
16385
16384
10.240mA
0.625µA = 1counts
0-20mA Range
4-20mA Range
Note 2) 4-20mA Range
20.000mA
32000
20.3835mA
32767
20.384mA
32000
Note 1) 4-20mA Range
4.000mA
0
4.077mA
154
4.0765mA
0
The following equations can be used to calculate count values:
4-20mA Range: Counts = (Current in mA - 4mA) x (32000 / 16mA)
0-20mA Range: Counts = (Current in mA ) x (32000 / 20mA)
Note 1: In 4-20mA mode, signal inputs below 4.077mA are converted to zero counts.
Note 2: In 4-20mA mode, signal inputs at 20.000mA or above 20.383mA are converted to
32000 counts