Siemens SIMATIC ET 200eco PN - Analog Value Representation for Measuring Ranges with SIMATIC S7; Measuring Ranges of the Analog Input Device in S7 Format

I/O device analog input/analog output
10.1 I/O device analog input
ET 200eco PN
182 Operating Instructions, 08/2016, A5E01250250-AJ
10.1.5
Analog value representation for measuring ranges with SIMATIC S7
Representation of analog values
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 representation of analog values of the analog input.
Table 10- 6 Representation of analog values (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 Sig
n
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" → -
10.1.6
Measuring ranges of the analog input device in S7 format
Voltage measuring ranges: Measuring range 1 to 5 V
Measuring range
1 to 5 V
Units
Range
Decimal
Hexadecimal
> 5.704 V 32767 7FFF
H
Overflow
5.704 V
32511
7EFF
H
Overrange
27649
6C01
H
5 V
27648
6C00
H
Nominal range
4 V
20736
5100
H
1 V + 144.7 µV
1
0001
H
1 V
0
0000
H
-1
FFFF
H
Underrange
0.296 V
-4864
ED00
H
< 0.296 V
32767
7FFF
H
Wire break
- 32768
8000
H
Underflow