Siemens SIMATIC NET PROFIBUS manual Topologies of Simatic NET Profibus Networks

Topologies of SIMATIC NET PROFIBUS Networks

A break on a fiber-optic cable between two modules is detected by the modules and the network is reconfigured to form an optical bus. The entire network remains operational.

If a module fails, only the DTEs or electrical segments attached to the module are separated from the ring; the remaining network remains operational as a bus.

The problem is indicated by LEDs on the modules involved and by their signaling contacts.

After the problem is eliminated, the modules involved cancel the segmentation automatically and the bus is once again closed to form a ring.

Note

To increase the availability, the duplex cables for the outgoing and incoming paths in the ring should be routed separately.

PROFIBUS Networks SIMATIC NET	2-11
6GK1970-5CA20-0AA1 Release 2 05/2000