Mrp - Siemens S7-300 Configuration Manual

Configuring the Ethernet CP with STEP 7
3.5 Media redundancy
3.5.2

MRP

The "MRP" method conforms to the Media Redundancy Protocol (MRP) specified in the
following standard:
IEC 62439-2 Edition 1.0 (2010-02) Industrial communication networks - High availability
automation networks Part 2: Media Redundancy Protocol (MRP)
The reconfiguration time after an interruption of the ring is a maximum of 0.2 seconds.
Requirements
Requirements for problem-free operation with the MRP media redundancy protocol are as
follows:
● MRP is supported in ring topologies with up to 50 devices. In topologies with X300 IE
switches, up to 100 nodes are supported.
Exceeding this number of devices can lead to a loss of data traffic.
● The ring in which you want to use MRP may only consist of devices that support this
function.
These include, for example, some of the Industrial Ethernet SCALANCE X switches,
some of the communications processors (CPs) for SIMATIC S7 and PG/PC or non-
Siemens devices that support this function.
● All devices must be interconnected via their ring ports.
● "MRP" must be activated on all devices in the ring (see section "MRP configuration
(Page 74)").
● The connection settings (transmission medium / duplex) must be set to full duplex and at
least 100 Mbps for all ring ports. Otherwise there may be a loss of data traffic.
– STEP 7: Set all the ports involved in the ring to "Automatic settings" in the "Options"
– WBM: If you configure with Web Based Management, the ring ports are set
72
tab of the properties dialog.
automatically to autonegotiation.
Configuring and commissioning S7 CPs for Industrial Ethernet
Configuration Manual, 09/2013, C79000-G8976-C182-13