Media Redundancy With Planned Duplication Of Frames (Mrpd) - Siemens SIMATIC PROFINET Function Manual

Functions
5.4 Media redundancy (ring topologies)
Ring port 1 / Ring port 2
Select one at a time those ports you want to configure as ring port 1 or ring port 2. The drop-
down list box shows the selection of possible ports for each device type. If the ports are set
at the factory, then the fields are unavailable.
If you use single-stage commissioning, use the preset ring ports in STEP 7.
Diagnostic interrupts
If diagnostic interrupts to the MRP state are to be output in the local CPU, select the
"Diagnostic interrupts" check box. The following diagnostic interrupts can be configured:
● Wiring or port error
Diagnostic interrupts will be generated for the following errors in the ring ports:
– A neighbor of the ring port does not support MRP.
– A ring port is connected to a non-ring port
– A ring port is connected to the ring port of another MRP domain.
● Interruption / return (redundancy manager only)
If the ring is interrupted and the original configuration is returned, diagnostic interrupts will
be generated. If both of these interrupts occur within 0.2 seconds, this indicates an
interruption of the ring.
You can respond to these events in the user program by programming the appropriate
response in the diagnostic error interrupt OB (OB 82).
5.4.3

Media Redundancy with Planned Duplication of frames (MRPD)

MRP extension "Media Redundancy with Planned Duplication of frames" (MRPD)
The MRP extension "Media Redundancy with Planned Duplication of frames" (MRPD)
provides the advantage that, in the case of a failure of a device or a line in the ring, all other
devices continue to be supplied with IO data without interruption and with short update times.
MRPD is based on IRT and MRP. To realize media redundancy with short update times, the
PROFINET devices participating in the ring send their data in both directions. The devices
receive this data at both ring ports so that there is no reconfiguration time.
Requirements for media redundancy with MRPD
● All the devices of the ring must support MRPD, for example interface module IM
155-6 PN HS as of firmware version 4.0.
● You have configured MRP for all the devices of the ring. You have assigned the MRP role
"Not device in the ring" to devices that are not located in the ring.
● You have configured IRT for all the involved components.
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PROFINET with STEP 7 V14
Function Manual, 09/2016, A5E03444486-AG