INVT Goodrive270 Series User Manual

Goodrive270 series VFD for fan and pump Communication protocol
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1#
15#
32#
6
#
Main control
device
Figure 9-5 Star connection
Use shielded cables, if possible, in multi-device connection. The baud rates, data bit check settings,
and other basic parameters of all the devices on the RS485 line must be set consistently, and
addresses cannot be repeated.
9.3.2 RTU mode
9.3.2.1 RTU communication frame structure
When a controller is set to use the RTU communication mode on a Modbus network, every byte (8
bits) in the message includes 2 hexadecimal characters (each includes 4 bits). Compared with the
ASCII mode, the RTU mode can transmit more data with the same baud rate.
Code system
• 1 start bit
• 7 or 8 data bits; the minimum valid bit is transmitted first. Each frame domain of 8 bits includes 2
hexadecimal characters (0–9, A–F).
• 1 odd/even check bit; this bit is not provided if no check is needed.
• 1 stop bit (with check performed), 2 bits (without check)
Error detection domain
• Cyclic redundancy check (CRC)
The following table describes the data format.
11-bit character frame (Bits 1 to 8 are data bits)
Start bit
BIT1
BIT2
BIT3
BIT4
BIT5
BIT6
BIT7
BIT8
Check bit
Stop bit
10-bit character frame (Bits 1 to 7 are data bits)
Start bit
BIT1
BIT2
BIT3
BIT4
BIT5
BIT6
BIT7
Check bit
Stop bit
In a character frame, only the data bits carry information. The start bit, check bit, and stop bit are used
to facilitate the transmission of the data bits to the destination device. In practical applications, you
must set the data bits, parity check bits, and stop bits consistently.
In RTU mode, the transmission of a new frame always starts from an idle time (the transmission time
of 3.5 bytes). On a network where the transmission rate is calculated based on the baud rate, the

INVT Goodrive270 Series Specifications

General

Control Mode	V/F control, Sensorless vector control
IP Rating	IP20
Cooling Method	Air cooling
Overload Capacity	150% for 60 seconds
Protection Functions	Overcurrent, Overvoltage, Undervoltage, Overheat, Overload, Short circuit
Communication	RS485, Modbus
Application	Water pump
Input Frequency	50Hz/60Hz
Output Voltage	0~Rated Voltage
Rated Current	Depends on the model
Operating Temperature	-10°C to +40°C
Storage Temperature	-20°C to 60°C
Humidity	<95% (non-condensing)
Altitude	Below 1000m

Summary

Change History

Preface

Safety Precautions

Safety Definitions and Warnings

Defines safety terms (Danger, Warning, Note) and lists warning symbols.

General Safety Guidelines

Covers essential precautions for handling, installation, operation, and maintenance.

Quick Startup Guide

Product Inspection and Environment Checks

Details unpacking, pre-use checks, and environmental requirements for VFD installation.

Basic Commissioning Steps

Outlines fundamental steps for initial VFD setup, motor parameter configuration, and autotuning.

Product Overview

Working Principles and Specifications

Explains the VFD's basic principles, technical specifications, and features.

Model Designation and Ratings

Details the VFD model designation code and product ratings for various power outputs.

VFD Structure and Components

Illustrates the physical structure and identifies the main components of the VFD.

Installation Guidelines

Mechanical Installation

Covers environment, direction, mounting methods, clearances, and cabinet installation.

Wiring Guidelines

Details main circuit, control circuit, external keypad, and wiring protection procedures.

Basic Operation Guidelines

Keypad Operation and Display

Explains LED and LCD keypad functions, parameter display, and editing.

Core VFD Configuration and Control Modes

Covers parameter configuration, autotuning, control modes (Vector, Space Voltage), and frequency settings.

Advanced Functions and Controls

Details Simple PLC, PID control, water pump control, and protection features.

Function Parameter List

Basic and Motor Parameters (P00-P03)

Covers basic functions, motor 1 parameters, vector control, and V/F control for motor 1.

Control and I/O Parameters (P04-P07, P09-P11)

Details V/F control for motor 2, input/output terminals, human-machine interface, enhanced functions, PID, and protection.

Specific Functions and Settings (P10, P12-P28, P90-P96)

Covers Simple PLC, motor 2 parameters, communication, status, HVAC, water pump, and protection functions.

Troubleshooting Common Faults

Fault Indicators and Reset

Explains how faults are indicated and how to reset them.

Fault History and Solutions

Lists common faults, their causes, and solutions for troubleshooting.

Interference Countermeasures

Addresses interference issues with sensors, RS485, motor cables, and RCDs.

VFD Maintenance

Periodical Inspection and Cooling Fan

Outlines routine checks for VFD components and procedures for cooling fan replacement.

Capacitor and Power Cable Maintenance

Describes capacitor reforming, replacement, and power cable inspection.

Communication Protocol

Modbus RTU Communication

Details Modbus protocol, RTU frame structure, error checks, and command examples.

Expansion Card Communication

Explains wiring and functions for PROFIBUS, CAN, and PROFINET expansion cards.

Technical Data and Compliance

Derating, Specifications, and EMC

Covers derating conditions, technical specifications, EMC requirements, and application standards.

Dimension Drawings

Keypad and VFD Mounting Dimensions

Provides detailed dimensions for keypads, VFDs, and mounting brackets.

Optional Peripheral Accessories

Filters, Reactors, and Cables

Details selection guidelines for filters, reactors, and power/control cables.

Breakers, Contactors, and Other Accessories

Covers selection of breakers, contactors, and other optional accessories.

Further Information

Product Queries and Feedback

Contact information for product queries, service, and manual feedback.