ABB AC 800F Mounting And Installation Instructions Manual page 113

4 Cabling the AC 800F
It is recommended to keep the link between the AC 800F or operator station and the
network concentrator as short as possible in this case. This reduces the risk that the
non-redundant link between the network concentrator and the AC 800F or operator
station fails. Ideally the network concentrators should be placed close to the AC 800F
or operator station.
If more than two nodes have to be linked, it is recommended to use a ring topology.
Figure 4-26 shows as an example the redundant connection of three nodes. Make
sure that the AUI cable shields are grounded properly.
Fig. 4-26 Redundant 10BaseFL cabling, case 2
The fiber optic cable links form a ring. Even if any of the links fails, the connection
between all three nodes is preserved. The three cables should be laid on separate
routes to increase safety in case of accidental damages (e.g. by excavators).
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