Danfoss VLT Midi Drive FC 280 Design Guide

5 RS485 Installation and Set-up
54
5.1 Introduction
54
5.1.1 Overview 54
5.1.2 Network Connection 54
5.1.3 Hardware Set-up 55
5.1.4 Parameter Settings for Modbus Communication 55
5.1.5 EMC Precautions 55
5.2 FC Protocol
55
5.2.1 Overview 55
5.2.2 FC with Modbus RTU 56
5.3 Network Conguration
56
5.4 FC Protocol Message Framing Structure
56
5.4.1 Content of a Character (byte) 56
5.4.2 Telegram Structure 56
5.4.3 Telegram Length (LGE) 56
5.4.4 Frequency Converter Address (ADR) 57
5.4.5 Data Control Byte (BCC) 57
5.4.6 The Data Field 57
5.4.7 The PKE Field 57
5.4.8 Parameter Number (PNU) 58
5.4.9 Index (IND) 58
5.4.10 Parameter Value (PWE) 58
5.4.11 Data Types Supported by the Frequency Converter 58
5.4.12 Conversion 58
5.4.13 Process Words (PCD) 59
5.5 Examples
59
5.5.1 Writing a Parameter Value 59
5.5.2 Reading a Parameter Value 59
5.6 Modbus RTU
60
5.6.1 Prerequisite Knowledge 60
5.6.2 Overview 60
5.6.3 Frequency Converter with Modbus RTU 60
5.7 Network Conguration
60
5.8 Modbus RTU Message Framing Structure
61
5.8.1 Introduction 61
5.8.2 Modbus RTU Telegram Structure 61
5.8.3 Start/Stop Field 61
5.8.4 Address Field 61
5.8.5 Function Field 61
5.8.6 Data Field 62
Contents Design Guide
MG07B102 Danfoss A/S © 03/2016 All rights reserved. 3

Danfoss VLT Midi Drive FC 280 Specifications

General

Brand	Danfoss
Model	VLT Midi Drive FC 280
Category	DC Drives
Language	English