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Motors I Automation I Energy I Transmission & Distribution I CoatingsModbus RTUCFW300User’s Manual

Modbus RTU User’s ManualSeries: CFW300Language: EnglishDocument Number: 10003806158 / 02Publication Date: 12/2018

ContentsCONTENTSCONTENTS . 3ABOUT THIS MANUAL . 5ABBREVIATIONS AND DEFINITIONS . 5NUMERICAL REPRESENTATION . 5DOCUMENTS . 51INTRODUCTION TO SERIAL COMMUNICATION . 62INTERFACE DESCRIPTION . 72.1RS485 COMMUNICATION MODULE (CFW300-CRS485) . 72.1.1RS485 module’s connector . 72.1.2RS485 Interface Characteristics . 72.1.3Terminating resistor . 82.1.4Indications . 82.1.5Connection with the RS485 Network . 82.2USB COMMUNICATION MODULE (CFW300-CUSB) . 82.2.1Indications . 92.3RS232 COMMUNICATION MODULE (CFW300-CRS232) . 92.3.1RS232 connector of the module . 92.3.2Indications . 92.3.3Connection to the RS232 Network. 93PROGRAMMING . 103.1SYMBOLS FOR THE PROPERTIES DESCRIPTION. 10P105 – 1ST/2ND RAMP SELECTION . 10P220 – LOCAL/REMOTE SELECTION SOURCE . 10P221 – SPEED REFERENCE SELECTION – LOCAL SITUATION . 10P222 – SPEED REFERENCE SELECTION – REMOTE SITUATION . 10P223 – FORWARD/REVERSE SELECTION – LOCAL SITUATION . 10P224 – RUN/STOP SELECTION – LOCAL SITUATION. 10P225 – JOG SELECTION – LOCAL SITUATION . 10P226 – FORWARD/REVERSE SELECTION – REMOTE SITUATION . 10P227 – RUN/STOP SELECTION – REMOTE SITUATION . 10P228 – JOG SELECTION – REMOTE SITUATION . 10P308 – SERIAL ADDRESS . 10P310 – SERIAL BAUD RATE . 10P311 – SERIAL INTERFACE BYTE CONFIGURATION . 11P313 – COMMUNICATION ERROR ACTION . 11P314 – SERIAL WATCHDOG . 12P316 – SERIAL INTERFACE STATUS . 12P680 – STATUS WORD . 12P681 – MOTOR SPEED IN 13 BITS . 13P682 – SERIAL CONTROL WORD. 14P683 – SERIAL SPEED REFERENCE . 144MODBUS RTU PROTOCOL . 164.1TRANSMISSION MODES . 164.2MESSAGE STRUCTURE FOR RTU MODE . 164.2.1Address . 164.2.2Function Code . 164.2.3Data Field . 164.2.4CRC . 16CFW300 3

Contents4.2.55OPERATION IN THE MODBUS RTU NETWORK – SLAVE MODE . 185.15.26AVAILABLE FUNCTIONS AND RESPONSE TIMES . 18MEMORY MAP. 18DETAILED DESCRIPTION OF THE FUNCTIONS . 206.16.26.36.46.57Time Between Messages . 16FUNCTION 03 – READ HOLDING REGISTER . 20FUNCTION 06 – WRITE SINGLE REGISTER . 20FUNCTION 16 – WRITE MULTIPLE REGISTERS . 21FUNCTION 43 – READ DEVICE IDENTIFICATION . 22COMMUNICATION ERRORS . 22FAULTS AND ALARMS RELATED TO THE MODBUS RTU COMMUNICATION . 24A128/F228 – TIMEOUT FOR SERIAL COMMUNICATION . 24I.APPENDICES. 25APÊNDICE A.APÊNDICE B.ASCII TABLE . 25CRC CALCULATION USING TABLES . 26CFW300 4

About this ManualABOUT THIS MANUALThis manual supplies the necessary information for the operation of the CFW300 frequency inverter using theModbus RTU protocol. This manual must be used together with the CFW300 user manual.ABBREVIATIONS AND DEFINITIONSASCIICRCEIATIARTUAmerican Standard Code for Information InterchangeCycling Redundancy CheckElectronic Industries AllianceTelecommunications Industry AssociationRemote Terminal UnitNUMERICAL REPRESENTATIONDecimal numbers are represented by means of digits without suffix. Hexadecimal numbers are represented withthe letter ‘h’ after the number. Binary numbers are represented with the letter ‘b’ after the number.DOCUMENTSThe Modbus RTU protocol was developed based on the following specifications and documents:DocumentMODBUS Application Protocol Specification, December28th 2006.MODBUS Protocol Reference Guide, June 1996.MODBUS over Serial Line, December 20th 2006.VersionV1.1bSourceMODBUS.ORGRev. JV1.02MODICONMODBUS.ORGIn order to obtain this documentation, consult MODBUS.ORG, which is nowadays the organization that keeps,publishes and updates the information related to the Modbus protocol.CFW300 5

Introduction to Serial Communication1 INTRODUCTION TO SERIAL COMMUNICATIONIn a serial interface the data bits are sent sequentially through a communication channel or bus. Severaltechnologies use the serial communication for data transfer, including the RS232 and RS485 interfaces.The directions that specify the RS232 and RS485 standards, however, do neither specify the character format,nor its sequence for the data transmission and reception. Therefore, besides the interface, it is also necessary toidentify the protocol used for the communication. Among the several existent protocols, one used a lot in theindustry is the Modbus RTU protocol.In the sequence the characteristics of the RS232, RS485 and USB serial interfaces available for the product willbe presented, as well as the Modbus RTU protocol for the use of this interface.CFW300 6

Interface Description2 INTERFACE DESCRIPTIONThe interfaces for serial communication RS485 or USB available for the CFW300 frequency inverter depend onthe selected communication module for the product. Following are presented information about the connectionand installation of the equipment, using different communication modules.2.1RS485 COMMUNICATION MODULE (CFW300-CRS485)Figure 2.1: Module with RS485 interfaceThis plug-in module for the CFW300 frequency inverter has one RS485 interface. This standard RS485 interfacehas two functions: Point to Point Connection with remote keypad, via mini USB 1 connector.Connection via RS485 for network operation, via terminals.DANGER!The mini USB connector is not USB compatible, therefore, It cannot be connected to USB ports.This connector only serves as the interface between the frequency inverter and Its remotekeypad.NOTE!Although RS485 communication signal is available on both connectors – mini USB and controlterminal – these signals are the same (internally). For this reason, it is not possible to use RS485interface as command source or reference source and remote keypad at the same time.2.1.1RS485 module’s connectorThe RS485 interface connections are available via control terminal using the following pin assignment:Table 2.1: RS485 connector pinout for the module (CFW300-CRS485)25262728292.1.2 12ConectorRS485 – A (-)RS485 – B ( )GNDShield (PE)N.C.DescriptionRS485 (Terminal A)RS485 (Terminal B)0V referenceCable shieldNo ConnectionRS485 Interface CharacteristicsThe interface follows the EIA/TIA-485 standard.It allows communication baud rates from 9600 up to 38400 Kbit/s.The interface is electrically isolated and with differential signal, which grants more robustness againstelectromagnetic interference.It allows the connection of up to 32 devices to the same segment. More devices can be connected by usingrepeaters 2.For connections that require distances greater than 3 meters, use remote keypad connection via control terminal.The limit of devices that can be connected on the network depends on the protocol used.CFW300 7

Interface Description A maximum bus length of 1000 meters.2.1.3Terminating resistorIt is necessary to enable a terminating resistor at both ends of the main bus for each segment of the RS485network. If the equipment located at both ends of the bus does not have termination resistors, use activeterminating to enable these resistors.Table 2.2: Configuration of the switches to configure the RS485Switch SettingS1.1 OFF e S1.2 OFFS1.1 ON e S1.2 ONS1.1 OFF e S1.2 ONS1.1 ON e S1.2 OFF2.1.4OptionRS485 Termination offRS485 Termination onThis combination is notallowedIndicationsDetails on the alarms, communications failures and communication states are made through the keypad (HMI)and product parameters.2.1.5Connection with the RS485 NetworkThe following points must be observed for the connection of the device using the RS485 interface: 2.2It is recommended the use of a shielded cable with a twisted pair of wires.It is also recommended that the cable has one more wire for the connection of the reference signal (GND).In case the cable does not have the additional wire, then the GND signal must be left disconnected.The cable must be laid separately (and far away if possible) from the power cables.All the network devices must be properly grounded, preferably at the same ground connection. The cableshield must also be grounded.Enable the termination resistors only at two points, at the extremes of the main bus, even if there arederivations from the bus.USB COMMUNICATION MODULE (CFW300-CUSB)Figure 2.2: Module with USB connectionFor this module, a USB interface with mini-USB conector is available. When connecting the USB interface, it willbe recognized as a USB to serial converter, and a virtual COM port will be created 3. Thus communication ismade with the drive via this COM port.The USB accessory also provides the connection to the remote keypad via standard RS485 interface.3It is necessary to install the USB driver on the CD-ROM supplied with the product. The COM port number created depends on theavailability in the operating system and, once connected, consult the hardware resources of the system to identify this port. .CFW300 8

Interface Description2.2.1IndicationsDetails on the alarms, communications failures and communication states are made through the keypad (HMI)and product parameters.2.3RS232 COMMUNICATION MODULE (CFW300-CRS232)Figure 2.3: Module with RS232 connection2.3.1RS232 connector of the moduleThe connection for the RS232 interface is available via terminals using the following pin assignment:Table 2.3: Pin assignment of the RS232 connector for the module .GNDDescriptionNo ConnectionReceiverTransmitterNo ConnectionReference 0 VIndicationsThe alarm, fault and status indications of the communication are made through the HMI and parameters of theproduct.2.3.3Connection to the RS232 NetworkFor the connection of the CFW300 frequency inverter using the RS232 interface, the following points must beobserved: The frequency inverter RX and TX signals must be connected respectively to the master TX and RX, besidesthe connection of the reference signal (GND).The RS232 interface is very susceptible to interferences. Therefore, the cable used for communication mustbe as short as possible – always shorter than ten meters.The passage of the cable must be done separately (and if possible distant) from the power supply cables.All network devices must be properly grounded, preferably to the same connection with the ground.CFW300 9

Programming3 PROGRAMMINGNext, the CFW300 frequency inverter parameters related to the Modbus RTU communication will be presented.3.1SYMBOLS FOR THE PROPERTIES DESCRIPTIONROCFGReading only parameterParameter that can be changed only with a stopped motor.P105 – 1ST/2ND RAMP SELECTIONP220 – LOCAL/REMOTE SELECTION SOURCEP221 – SPEED REFERENCE SELECTION – LOCAL SITUATIONP222 – SPEED REFERENCE SELECTION – REMOTE SITUATIONP223 – FORWARD/REVERSE SELECTION – LOCAL SITUATIONP224 – RUN/STOP SELECTION – LOCAL SITUATIONP225 – JOG SELECTION – LOCAL SITUATIONP226 – FORWARD/REVERSE SELECTION – REMOTE SITUATIONP227 – RUN/STOP SELECTION – REMOTE SITUATIONP228 – JOG SELECTION – REMOTE SITUATIONThese parameters are used in the configuration of the command source for the CFW300 frequency inverter localand remote situations. In order that the device be controlled through the Modbus RTU interface, the options‘serial’ available in these parameters, must be selected.The detailed description of these parameters is found in the CFW300 programming manual.P308 – SERIAL ADDRESSRange:Properties:1 to 247CFGDefault: 1Description:It allows programming the address used for the inverter serial communication. It is necessary that each device inthe network has an address different from all the others.P310 – SERIAL BAUD RATERange:Properties:0 9600 bits/s1 19200 bits/s2 38400 bits/sCFGDefault: 1Description:It allows programming the baud rate for the serial communication interface, in bits per second. This baud ratemust be the same for all the devices connected to the network.CFW300 10