Equipment Description
Communication
Overview
Safety-Related Communication
The Safety PLCs and remote output devices communicate with each other and the PC over Ethernet using SafeEthernet protocol.
The Safety PLCs communicate with each other and with a PC through a star or linear Ethernet layout. A PC can be connected at any place in the network.
The communication section is connected to the safe microprocessor system. It controls communication between PES and other systems via powerful interfaces, such as 100 BaseT: SafeEthernet, Modbus TCP/IP
Communication via switches
The switch integrated into each system for SafeEthernet communication is shown on the block diagram (see Block Diagram, p. 26).
In contrast to a hub, a switch can store data packets for a short period of time in order to establish a temporary connection between two communication partners (transmitter/receiver) for transferring data. This way, collisions (typically occurring in hubs) can be avoided, and the load on the network can be reduced. For controlled data transfer, every switch needs an address/port relation table. This table will be automatically generated in a
The switch automatically switches between the transfer rates of 10 and 100 MBit/s full and half duplex transmissions.
The switch controls communication between different devices. The switch can address up to 1000 absolute MAC addresses.
Autocrossing recognises if cables with crossed wires have been connected, and the switch adjusts accordingly.
For networking via Ethernet, the XPSMF2DO801 safety remote output device is equipped with two connections arranged on the lower side panel of the case. Various systems can be networked as required via Ethernet star or line configuration. A PC can also be connected wherever required.
Note: When building the network, ensure that no network loops are formed. The system must receive data along only one path.
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