Process Image; Overview - WAGO 750-489 Manual

WAGO-I/O-SYSTEM 750
750-489 4AI RTD/TC/Strain Gauge Ex i
4

Process Image

The I/O module 750-489 provides one control/status byte (8 bits) and one data
word (16 bits) per channel.
The I/O module records input current and voltage ranges with a 16-bit processing
value resolution.
The digitized measured value is transmitted to the process image of the fieldbus
coupler/controller in a data word (16 bits) as an input byte "0" (low) and input byte
"1" (high). The I/O module can be parameterized (Siemens S5 FB250 format) in
such a way that additional error and status information, which can be used to
identify an error, can be transmitted in the three lowest (B0 ... B2) of the sixteen
bits. If the measurement is below or above the measurement range, bit B0 is set
to 1, and, in the event of an overflow or underflow, bit B1 is set to 1. Bit B2 is not
used. The measured value is then mapped with a resolution of thirteen bits to bits
B3 ... B15.
The WAGO-I/O-CHECK commissioning tool can be used to parameterize the
required operating mode. Alternatively, the I/O module can also be
parameterized via PROFIBUS and PROFINET device description (GSD file).
The parameterization description can be found in section "Commissioning" >
"Configuration and Parameterization via GSD file."
4.1

Overview

Representation of control/status bytes depends on fieldbus
coupler/controller!
The I/O module always provides a complete process image, including control
bytes/status bytes, to the fieldbus coupler/controller. The WAGO-I/O-CHECK
commissioning tool accesses this complete commissioning process image. The
fieldbus coupler/controller uses a different process image for provision of cyclic
process data via the fieldbus. Representation of the control bytes/status bytes
may be suppressed in this other process image, depending on the fieldbus
coupler/controller being used
Process Image
Version 1.1.0, valid from FW Version 02
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Manual