Related Manuals for ABB C250
Summary of Contents for ABB C250
- Page 1 User Guide Control IM/C250–MOD_2 MODBUS (RTU) Communications Option C250 and V250...
- Page 2 Electrical Safety This instrument complies with the requirements of CEI/IEC 61010-1:2001-2 "Safety requirements for electrical equipment for measurement, control, and laboratory use". If the instrument is used in a manner NOT specified by the Company, the protection provided by the instrument may be impaired. Symbols One or more of the following symbols may appear on the instrument labelling: Warning –...
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Page 3: Table Of Contents
CONTENTS INTRODUCTION ................... 2 ELECTRICAL INSTALLATION ..............3 2.1 Host Computer Serial Communications ..........3 2.2 OPTO22 Boards for use with Personal Computers ....... 3 2.3 Two-wire and Four-wire Connection ............. 3 2.4 Pull-up and Pull-down Resistors ............4 2.5 Termination Resistor ................5 2.6 Serial Connections ................. -
Page 4: Introduction
1 INTRODUCTION This Operating Guide describes the COMMANDER 250/V250 MODBUS serial data communications option and must be used in conjunction with the standard User Guide (part no. IM/C250 or IM/V250) supplied with the instrument. Warnings. • If the equipment is used in a manner not specified by the Company, the protection provided by the equipment may be impaired. -
Page 5: Electrical Installation
2.3 Two-wire and Four-wire Connection – Figs. 2.1 and 2.2 MODBUS serial communications must be configured as either two-wire or four-wire serial links – see Figs. 2.1 and 2.2. Two-/four-wire operation must also be selected in the Configuration Mode – see Section 3.1. C250 Host Computer V250 Refer to page 2 1.8kΩ... -
Page 6: Pull-Up And Pull-Down Resistors
2 1.8kΩ Pull-down Tx– Resistor 1.8kΩ Pull-up Rx– Resistor 1.8kΩ Pull-down Resistor Fig. 2.2 Pull-up and Pull-down Resistors (Four-wire Operation) C250 / V250 Refer to page 2 Master First Slave Last Slave Rx– Tx– Host Computer Tx– Rx– 120Ω... -
Page 7: Termination Resistor
Up to 300m e.g. Belden 9502 or equivalent. – twin twisted pair with separate foil screens and integral drain Up to 1200m wires, e.g. Belden 9729 or equivalent. C250 V250 Refer to page 2 OPTO22 Adaptor Board Connections Tx–... -
Page 8: Configuration
MODBUS link must be assigned a unique address in the range 1 to 99. See Addr section 4.4 of the relevant User Guide (MODBUS Address Frame, S – Serial Communication Configuration T – Serial Communications Parity C250/V250 C250/V250 PrSt PrSt 2100... -
Page 9: Modbus Protocol
4 MODBUS PROTOCOL Notes. • The COMMANDER 250/V250 operates as a MODBUS, Remote Terminal Unit (RTU) slave. • Parity checking – detects transmission errors in individual characters. • Cyclic redundancy checking – detects errors in the master messages and slave responses. •... -
Page 10: Modbus Function Codes
…4 MODBUS Protocol 4.2 MODBUS Function Codes The function code instructs the addressed slave which function to perform. Table 4.1 shows the function codes, and describes the action they initiate. Function Function Description Code Title Read Read up to 16 consecutive discrete (Boolean) points Coil Status from a specific starting point. -
Page 11: Modbus Functions
5 MODBUS FUNCTIONS This section shows typical examples of MODBUS function codes 01, 03, 05, 06, 08 and 16. Not all addressable parameters used in the examples which follow are valid for both instrument types – see Sections 7.1 to 7.4. 5.1 Read Coil Status –... -
Page 12: Read Holding Register - Function Code 03
…5 MODBUS Functions 5.2 Read Holding Register – Function Code 03 5.2.1 Read Holding Register Query The Read Holding Register Query obtains the contents of up to eight holding registers in the addressed slave. Note. The data start register must contain the offset address of the first register to be accessed, e.g. -
Page 13: Force Single Coil - Function Code 05
5 MODBUS Functions… 5.3 Force Single Coil – Function Code 05 5.3.1 Force Single Coil Query This message forces a single coil either ON or OFF. The data value 65,280 (FF00 HEX) sets the coil ON and the value zero turns it OFF. All other values are illegal and have no effect on coil status. -
Page 14: Preset Single Register - Function Code 06
…5 MODBUS Functions Preset Single Register – Function Code 06 5.4.1 Preset Single Register Query The Preset Single Register Query modifies the contents of a holding register. Note. Function codes 05, 06 and 16 are the only messages that are recognized as valid for broadcast. -
Page 15: Loopback Test - Function Code 08
5 MODBUS Functions… Loopback Test – Function Code 08 5.5.1 Loopback Test Query The Loopback Test Query tests the MODBUS system and does not affect the operation of the slave. Variations in the response may indicate faults in the MODBUS system. -
Page 16: Write Multiple Registers - Function Code 16
…5 MODBUS Functions Write Multiple Registers – Function Code 16 5.6.1 Write Multiple Registers Query This message is used to change the contents of up to eight holding registers at a time. When used with slave address zero (broadcast mode) all slave controllers load the selected registers with the contents specified. -
Page 17: Exception Responses
6 EXCEPTION RESPONSES The exception response codes sent by the slave are shown in Table 6.1. When a slave detects one of these errors, it sends a response message to the master consisting of slave address, function code, error code and error check fields. Exception Exception Response Exception Response... -
Page 18: Addressable Parameters
7 ADDRESSABLE PARAMETERS 7.1 COMMANDER 250/V250 – Coils Coil No. Variable Label Read/Write Limits/Values Process Variable Fail State 1 = Failed Remote Set Point Fail State 1 = Failed A/D Converter Fail State 1 = Failed Alarm State 1 1 = Active Alarm Indicator 1 1 = On Alarm State 2... -
Page 19: Control Settings
7 ADDRESSABLE PARAMETERS… …7.2 COMMANDER 250/V250 – Registers 7.2.2 Control Settings Register Variable Label Read/Write Limits/Values Process Variable Input –999 to 9999 Control Set Point –999 to 9999 Output 1 –80 to 1100 Auto/Manual State 0 = Auto; 1 = Manual 0 = Local 1 = Remote 2 = Fixed Set Point 1... -
Page 20: Alarm Settings
…7 ADDRESSABLE PARAMETERS …7.2 COMMANDER 250/V250 – Registers 7.2.3 Set Points Register Variable Label Read/Write Limits/Values Set Point High –999 to 9999 Set Point Low –999 to 9999 Local Set Point –999 to 9999 Remote Set Point Input –999 to 9999 Fixed Set Point 1 –999 to 9999 Fixed Set Point 2... - Page 21 NOTES...
- Page 22 NOTES...
- Page 23 We provide a comprehensive after sales service via a Worldwide Service Organization. Contact one of the following offices for details on your nearest Service and Repair Centre. United Kingdom ABB Limited Tel: +44 (0)1480 475 321 Fax: +44 (0)1480 217 948 United States of America ABB Inc.
- Page 24 ABB has Sales & Customer Support expertise The Company’s policy is one of continuous product in over 100 countries worldwide improvement and the right is reserved to modify the information contained herein without notice. www.abb.com Printed in UK (02.04) © ABB 2004 ABB Limited ABB Inc.