ELAP MEM440-Bus, Инструкция по эксплуатации

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MEM-BUS
EtherNet/IP™ ENCODER
Instruction Manual
ENIP_Manual_ENG 17/07/2018
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A DLR network is a single-fault-tolerant ring network that is intended for the interconnection of automation
devices. DLR topology is advantageous as it can tolerate a break in the network. If a break is detected, the
signals are sent out in both directions.
The EtherNet/IP™ specification include the Device Level Ring (DLR) protocol, allowing multi-port devices to
be connected in a ring topology. DLR provides for fast network fault detection and recognition in order to
support the most demanding control applications. For example, a ring of 50 nodes implementing the DLR
protocol has a worst case fault recovery time of less than 3 ms.
The DLR protocol operates at layer 2, in the OSI model. The presence of the ring topology and the operation
of the DLR protocol are transparent to higher layers protocols, such as TCP/IP and CIP, with the exception
of a DLR object that provides a DLR configuration and diagnostic interface via CIP.
1.6 CIP™ Object Model
EtherNet/IP uses an object model for network communication wherein all functions and data of a device
are defined. CIP objects are organized in Classes, Instances and Attributes.

Class
It contains related objects of a device, which is organized in instances.

Instance
It consists of different attributes that describe the properties of the instance. Different instances of
a class have the same services, the same behavior, and the same attributes. They can, however,
have different values.

Attributes
They represent the data that a device provides over EtherNet/IP. The attributes include the current
values of a configuration or an input. Typical attributes are configuration and status information.

Services
They are used to access the classes or the attributes of a class or to generate specific events. These
services execute defined actions such as reading/writing the attributes.