Operating hardware
4.4 Media redundancy
CP 1604 / CP 1616
Operating Instructions, 02/2017, C70000-G8976-C218-08
81
Note
Starting up and restarting
The MRP settings are still effective after a restart of the device or a power failure and hot
restart.
Note
Prioritized startup
If you configure MRP in a ring, you cannot use the "prioritized startup" function in PROFINET
applications on the devices involved.
If you want to use the "prioritized startup" function, then disable MRP in the configuration.
In the STEP 7 configuration, set the role of the relevant device to "Not a node in the ring".
Domain
Single MRP rings
If you want to configure a single MRP ring, leave the factory setting "mrpdomain 1" in the
"Domain" drop-down list.
All devices configured in a ring with MRP must belong to the same redundancy domain. A
device cannot belong to more than one redundancy domain.
If you leave the setting for "Domain" as the factory set "mrpdomain-1", the defaults for "Role"
and "Ring ports" also remain active.
MRP multiple rings
If you configure multiple MRP rings, the nodes of the ring will be assigned to the individual
rings with the "Domain" parameter.
Set the same domain for all devices within a ring. Set different domains for different rings.
Devices that do not belong to the same ring must have different domains.
Role
The choice of role depends on the following use cases.
●
You want to use MRP in a topology with one ring only with Siemens devices and without
monitoring diagnostic interrupts:
Assign all devices to the "mrpdomain-1" domain and the role "Manager (Auto)".
The device that actually takes over the role of redundancy manager, is negotiated by
Siemens devices automatically.
●
You want to use MRP in a topology with multiple rings only with Siemens devices and
without monitoring diagnostic interrupts (MRP multiple rings):
–
Assign the device that connects the rings the role of "Manager".
–
For all other devices in the ring topology, select the role of "Client".
