Beckhoff EL3773, Documentation

Page: 78 / 179

Commissioning
EL3773 78 Version: 2.5
Fig. 90: Basic EtherCAT Slave Diagnosis in the PLC
The following aspects are covered here:
Code Function Implementation Application/evaluation
A The EtherCAT Master's diagnostic infor-
mation
updated acyclically (yellow) or provided
acyclically (green).
At least the DevState is to be evaluated for
the most recent cycle in the PLC.
The EtherCAT Master's diagnostic informa-
tion offers many more possibilities than are
treated in the EtherCAT System Documenta-
tion. A few keywords:
• CoE in the Master for communication
with/through the Slaves
• Functions from TcEtherCAT.lib
• Perform an OnlineScan
B In the example chosen (EL3102) the
EL3102 comprises two analogue input
channels that transmit a single function
status for the most recent cycle. Status
• the bit significations may be
found in the device
documentation
• other devices may supply
more information, or none
that is typical of a slave
In order for the higher-level PLC task (or cor-
responding control applications) to be able to
rely on correct data, the function status must
be evaluated there. Such information is
therefore provided with the process data for
the most recent cycle.