SIOL-EI8B-USER-M
13
Description
Powered by
Version 1, May 2022
3.3.2. RPI
Requested Packet Interval (RPI)
When setting up an EtherNet/IP system, the RPI value must be carefully set in the scanner. The RPI
value determines the speed at which the scanner sends EtherNet/IP messages (packets). It also
determines the maximum speed at which the bus node sends messages.
The scanner sends the RPI when establishing a connection with a bus node so the system uses the same
time base. The RPI is also the interval at which the scanner will expect a response. An RPI that is too
short will result in increased network traffic.
The system slows as it processes the additional traffic because traffic on the network that is not intended
for the IO-Link devices must also be evaluated. The delays may make the system unable to meet the RPI.
The controller will report an error (timeout) if the response time of the device exceeds the set RPI time by
a factor of 4.
Please note:
a | Configurations which require RPI times shorter than 10ms must be tested in advance for correct
operation.
b | The minimum supported RPI time is 1 ms.
For further information, refer to
Section 8.2, “RPI configuration”
3.3.3. Device Level Ring (DLR)
Device Level Ring (DLR)
Device Level Ring (DLR) is a protocol which allows media redundancy in a ring topology, e.g. for
EtherNet/IP™ devices.
A ring network consists of at least one ring supervisor and any desired number of devices.
There are two different methods of building the topology and detecting cable breaks inside the ring:
a | Beacon-based
b | Announce-based
Devices which support DLR must have implemented the DLR object (0x47) which details configuration
and diagnostic. The use of modules which are not DLR-compliant in an EtherNet/IP ring network is not
excluded. However, it results in a higher ring recovery time when the ring topology is interrupted.
NOTE
The modules described in this manual support the beacon-based DLR technology. The described
modules do not support the ring supervisor function and can not be used as ring supervisor.
