Redundancy

Ethernet POWERLINK is redundancy-capable. Both the stations and the master can be redundant:

• With ring redundancy, the stations are connected in a ring to 2 ports of the master. In case of an error, the master recognizes that the telegrams are not arriving at the end of the ring and henceforth sends the telegrams on both ports.
• In the case of partial ring redundancy, the principle is similar, but only some of the stations are present in the ring and are therefore redundancy-capable.
• With master redundancy, 2 or more masters are present in the network. One master operates as a managing node (MN) and the other masters act as stations in hot standby mode. If a failure of the MN is detected, the redundant master is activated immediately without a restart and takes over the task of the failed MN.