GE LM10, Instruction Manual

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CHAPTER A: DEVICENET OVERVIEW
LM10 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL A–5
The Object Model:
The Object Model provides a template for organizing and implementing the Attributes,
Services and Behaviors of the components of a DeviceNet product.
The model provides an addressing scheme for each Attribute consisting of four
components i.e Node Address, Object Class Identifier, Instance Number, and Attribute
Number. This four-level address is used in conjunction with an Explicit Messaging
Connection to transfer the data from one place to another on a DeviceNet network.
Device Profiles:
To promote the interchangeability of alike devices, a “Device Profile” of main device
classes for industrial automation have to be specified that secure the same basic
(“standard”) behavior of devices of different manufacturers.
Beside a description of the device functionality, the device model must also provide a
description of the device identity, version number, status, diagnostic information,
communication facilities, and configuration parameters.
A DeviceNet device profile must contain the following information:
• An object model for the device type.
• The I/O data format for the device type.
• Configuration data and the public interfaces to that data. This information is
contained in an Electronic Data Sheet (EDS file) included with the device.
The DeviceNet specification defines an Electronic Data Sheet which is a simple file format
that allows product-specific information to be made available by vendors for all other
vendors. This makes possible user-friendly configuration tools that can be easily updated
without having to constantly revise the configuration software tool.