Rockwell-automation 284E ArmorStart with EtherNet/IP - User Manual Instrukcja Użytkownika Pobierz pdf (Strona 62)

62 Rockwell Automation Publication 280E-UM001B-EN-P - July 2012

Chapter 3 Introduction to EtherNet/IP and Device Level Ring Technology

Device Level Ring (DLR)

Introduction

A DLR protocol defines a set of behaviors, refer to Figure44. A ring supervisor

keeps packets of information from circulating infinitely around the ring by

blocking one of the ports. A beacon frame constantly is detected on both ring

supervisor ports. If a beacon frame is not detected the supervisor detects the

physical layer issue and reconfigures the network to a linear topology without the

loss of any node communication or data. Once repaired the ring supervisor

reconfigures back to ring mode.

Figure 44 - DLR Protocol

As shown in Figure45, when a physical layer failure is detected the adjacent

nodes to the fault generate a link status message that the ring supervisor

acknowledges. The ring supervisor unblocks the port to allow communication.

The neighboring nodes to the fault identify the fault and reconfigure themselves

to support a linear topology. Now, both the ring supervisor and nodes are

configured to support a linear topology.

IMPORTANT

Products with EtherNet/IP embedded switch technology have two ports to connect to

a linear or DLR network in a single subnet.

You cannot use these ports as two Network Interface Cards (NICs) connected to two

different subnets.

1 2 ... 57 58 59 60 61 62 63 64 65 66 67 ... 347 348

Brak uwag

Rockwell-automation 284E ArmorStart with EtherNet/IP - User Manual Instrukcja Użytkownika Strona 62