Danfoss VLT Compressor Drive CDS 803 Design Manual page 5

Contents
7.5 Examples
7.6 Modbus RTU Overview
7.7 Network Configuration
7.8 Modbus RTU Message Framing Structure
7.9 How to Access Parameters
7.10 Examples
MG18N202
Design Guide
7.4.1 Content of a Character (byte)
7.4.2 Telegram Structure
7.4.3 Telegram Length (LGE)
7.4.4 Frequency Converter Address (ADR)
7.4.5 Data Control Byte (BCC)
7.4.6 The Data Field
7.4.7 The PKE Field
7.4.8 Parameter Number (PNU)
7.4.9 Index (IND)
7.4.10 Parameter Value (PWE)
7.4.11 Data Types Supported by the Frequency Converter
7.4.12 Conversion
7.4.13 Process Words (PCD)
7.6.1 Prerequisite Knowledge
7.6.2 What the User Should Already Know
7.6.3 Overview
7.6.4 Frequency Converter with Modbus RTU
7.8.1 Introduction
7.8.2 Modbus RTU Telegram Structure
7.8.3 Start/Stop Field
7.8.4 Address Field
7.8.5 Function Field
7.8.6 Data Field
7.8.7 CRC Check Field
7.8.8 Coil Register Addressing
7.8.9 How to Control the Frequency Converter
7.8.10 Function Codes Supported by Modbus RTU
7.8.11 Modbus Exception Codes
7.9.1 Parameter Handling
7.9.2 Storage of Data
7.10.1 Read Coil Status (01 hex)
7.10.2 Force/Write Single Coil (05 hex)
7.10.3 Force/Write Multiple Coils (0F hex)
7.10.4 Read Holding Registers (03 hex)
Danfoss A/S © 12/2015 All rights reserved.
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