Analog electronic modules
4.2 Analog value representation
ET 200S
Manual, Edition 10/2005, A5E00514527-01
4-3
Sign
The sign (S) of the analog value is always in bit number 15:
• "0" → +
• "1" → –
Measurement resolution
The following table shows the representation of the binary analog values and the
corresponding decimal and hexadecimal representation of the units of the analog values.
The table shows the resolutions 11, 12, 13, and 15 bit + sign. Each analog value is entered
left aligned in the ACCU. The bits marked with "x" are set to "0".
Table 4-3 Measured Value Resolution of the Analog Values (SIMATIC S7 Format)
Units Analog Value
Resolution in Bits
Decimal Hexadecimal High byte Low byte
11+S 16 10
H
S 0 0 0 0 0 0 0 0 0 1 x x x x
12+S 8 8
H
S 0 0 0 0 0 0 0 0 0 0 1 x x x
13+S 4 4
H
S 0 0 0 0 0 0 0 0 0 0 0 1 x x
15 + sign 1 1
H
S 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Note
This resolution does not apply to temperature values. The converted temperature values are
the result of a conversion in the analog electronics module.
Note
The following applies with temperature measurements: When leaving the linearized nominal
range, the existing gradient of the characteristic curve is retained in the overflow and
underflow range.
To Next Page
Loading...
