2AI TC ST analog electronic module (6ES7134-4JB00-0AB0)
Manual, 04/2007, A5E01076883-01
17
Analog value representation
4
4.1 Introduction
Electronic modules with analog outputs
With the electronic module with analog inputs, continuously variable signals, such as those
occurring in temperature measurement and resistance measurement, can be acquired,
evaluated, and converted to digital values for further processing.
4.2 Analog value representation for measuring range with SIMATIC S7
Analog value representation
With the same nominal range, the digitized analog value is the same for input and output
values. Analog values are represented in two's complement.
The following table shows the analog value representation of the analog electronic modules.
Table 4-1 Analog value representation (SIMATIC S7 format)
Resolution Analog value
Bit number 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Significance of the bits S 2
14
2
13
2
12
2
11
2
10
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
Sign
The sign (S) of the analog value is always in bit number 15:
● "0" → +
● "1" → –