Download Operating Instructions - VEGAPULS 68

Supplement
Examples of telegram configuration
In the following you will see how the modules can be combined and how the appendant data
telegram is structured.
Example 1 (standard setting) with distance value and additional cyclical value:
l
l
AI (PA-OUT)
Additional Cyclic Value
Byte-No.
Format
Value
1
2
3
4
IEEE-754Floating point value
PA-OUT
(FB1)
5
Status
Status
(FB1)
6
7
8
9
IEEE-754Floating point value
Additional Cyclic
Value
10
Status
Status
Example 2 with distance value without additional cyclical value:
l
l
AI (PA-OUT)
Free Place
Byte-No.
Format
Value
1
2
3
4
IEEE-754Floating point value
PA-OUT
(FB1)
5
Status
Status
(FB1)
Note:
Bytes 6-10 are not used in this example.
Data format of the output signal
Byte4 Byte3 Byte2 Byte1 Byte0
Status
Value (IEEE-754)
Fig. 40: Data format of the output signal
The status byte corresponds to profile 3.0 "Profibus PA Profile for Process Control Devices"
coded. The status "Measured value OK" is coded as 80 (hex) (Bit7 = 1, Bit6 … 0 = 0).
66
VEGAPULS 68 - Profibus PA
29263-EN-070305
The measured value is transferred as a 32 bit floating point number in the IEEE-754 format.