ATV303 Modbus 通讯手册 (English) 本文档是最新的，但可能会参考过时产品。

This document provides information for the Altivar 303 variable speed drives for asynchronous motors, focusing on Modbus communication capabilities. It covers connection to RS485 bus, configuration of the Modbus serial port, and IO Scanner configuration parameters. The document details supported Modbus functions including Read Holding Registers, Write Multiple Registers, and Read Device Identification. It explains the ATV303 state machine based on IEC 61800-7 standard, including status word and command word descriptions. The guide includes practical application examples demonstrating connection to M218 PLC with Modbus master serial port. Technical specifications cover RS485 bus schematics, protection against interference, communication parameters, and CRC16 calculation methods. The document is designed for qualified personnel responsible for installation, configuration, and maintenance of Schneider Electric Altivar 303 drives. Note: AI-generated document summary. Please check the original document for detailed information.