WAGO-I/O-SYSTEM 750 XTR
Process Image 31
750-483/040-000 2AI 0-30 VDC Diff XTR
Manual
Version 1.1.0
4
Process Image
Mapping of process data in the process image of fieldbus systems
The representation of the I/O modules’ process data in the process image
depends on the fieldbus coupler/controller used. Please take this information as
well as the particular design of the respective control/status bytes from the
section “Fieldbus Specific Design of the Process Data” included in the description
concerning the process image of the fieldbus coupler/controller used.
Evaluation of Status Byte
Some fieldbus systems can process status information of process value by
means of a status byte.
This status byte can be displayed via the commissioning tool
WAGO-I/O-
CHECK
.
However, processing via the fieldbus coupler/controller is optional, which means
that accessing or parsing the status information depends on the fieldbus system.
The 750-483/040-000 analog input module transfers 16-bit measued values and
8 status bits (optional) per channel.
The digitized measured value is transferred to the process image of the
coupler/controller in a data word (16 bit) as input byte 0 (low) and input byte 1
(high).
This value is mapped at a resolution of 14 bit to bit B1 … B14.
The status of the first least significant bit B0 is not defined in the range from
0 V … +30 V. Therefore, in the “Process Image” table, it is shown as “X”.
The hexadecimal and decimal measured values in the table are specified under
the assumption that the first bit has the status “0”.
If status “1” is taken into consideration for the bit, the decimal measured value is
higher than in the table by a value of 1.
For the 750-483/040-000, the input voltage range of 0 V … 30 V is scaled to the
numeric value range of 0x0000 … 0x7FFF.
