Operating instructions Register sensors RS25
Operation using Ethernet Powerlink
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10 Operation using Ethernet Powerlink
10.1 Ethernet Powerlink interface
The fi gure below shows a typical example of an Ethernet Powerlink network.
Fig. 27: Example of an Ethernet Powerlink network
10.2 Cyclical and acyclical data exchange
Cyclical data exchange is controlled via a PLC and is subject to strict time
constraints. A fi xed time window is assigned to every participant (node) for
the responses to requests from the PLC. To keep cycle times low, the PLC
determines whether it sends a request to the sensor on every cycle or only
on every second or third cycle. The asynchronous phase begins once the
cyclical phase is complete. In this phase, the participants (nodes) can send
asynchronous data.
During cyclical data exchange, critical information, requests, and com-
mands are transferred, such as:
• Time-critical data from the PLC to the register sensor
• Time-critical data from the register sensor to the PLC, such as
"key codes" and "print marks"
During acyclical data exchange, non-critical information, requests, and
commands are transferred:
• Confi guration data from PLC > register sensor and register sensor > PLC
• Diagnostic data from PLC > register sensor and register sensor > PLC
