Atlas Copco PowerMACS 4000, User Manual

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Peripheral Devices
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Only shared signals can be mapped in the fieldbus form. A shared signal is defined by having its name
start with “SI_” or “SO_”.
Complex data types can be mapped even if their size exceeds the declared fieldbus size. Regular data
types will not be added if their size exceeds the declared fieldbus size.
When pressing the Apply button, the mapped signal in the fieldbus are being moved to the defined
address in the fieldbus area in the PLC.
A signal being deleted in the fieldbus form is moved back to the first free address in the shared area in the
PLC when pressing
Apply .
Monitoring
When connected to a TC, fieldbus data is monitored in the form. A snapshot of the fieldbus data is taken
once a second and sent to TTPM from the TC. The monitored values of the PLC signals are based on the
fieldbus data and not taken directly from the PLC. This means that if the user connects to a TC without
having pressed Apply in the fieldbus form, the signal values in the fieldbus form might not be the same as
in the PLC.
Values for signals and variables will be shown in the listview. The "value" column in the listview is empty
when not connected.
Since the refreshing of values in this form is slower than then PLC, very quick data changes in the PLC
can occur without being noticed in this form.