Beckhoff ELX3312, Руководство по эксплуатации

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Parameterization and programming
ELX3312 and ELX3314 62 Version: 1.3.0
5.5 Interference from equipment
When operating the ELX331x analog EtherCAT terminals, high frequency superimposed signals from
interfering devices (e.g. proportional valves, stepper motors or DC motor output stages) can be picked up by
the terminal. In order to guarantee interference-free operation, we recommend the use of separate power
supply units for the terminals and the interference-causing devices.
5.6 Wire break detection
The ELX331x terminals provide a wire break detection of the connected thermocouple. A periodical testing
current of up to 1 mA will be given to the thermocouple for detection. No voltage measurement takes place
during test.
Due to particular cases, the testing current could have a disturbing effect, the wire break detection can be
disabled by CoE object
0x80n0:0E [ } 74] (Disable wire break detection).
5.7 Process data
This section describes the individual PDOs and their content. A PDO (Process Data Object) is a unit on
cyclically transmitted process values. Such a unit can be an individual variable (e.g. the temperature as a 16-
bit value) or a group/structure of variables. The individual PDOs can be activated or deactivated separately
in the TwinCAT System Manager. The ‘Process data’ tab is used for this (visible only if the terminal is
selected on the left). A change in the composition of the process data in the TwinCAT System Manager
becomes effective only after restarting the EtherCAT system.
5.7.1 Selection of process data
The process data of the ELX3312 are set up in the TwinCAT System Manager. The PDOs can be activated
or deactivated separately. The ‘Process data’ tab is used for this (visible only if the terminal is selected on
the left).