ABB C1900 Series, Installation Manual

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1
CONTENTS 1 INTRODUCTION
Information.
• The COMMANDER 1900 Series is extended by the
addition of a serial data communication option
designed for use with SCADA systems.
• RS422/485 Communication standard.
• Modbus RTU protocol – for master (host computer)
to slave (COMMANDER 1900) system.
• Isolated (500V) from rest of instrument.
• 3 and 5 Wire communication supported.
• Baud rate – from 1200 to 9600.
• Parity-checking – of message available.
Section Page
1 INTRODUCTION ......................................................... 1
2 ELECTRICAL INSTALLATION .................................. 2
2.1 Selection of Serial Communication
Adaptors for Personal Computers ................... 2
2.2 Recommended OPTO22 Boards ..................... 2
2.3 Pull-up and Pull-down Resistors ...................... 2
2.4 Termination Resistors ....................................... 4
2.5 RS485/422 Standard ........................................ 4
2.6 Serial Connections ........................................... 5
3 ADVANCED CONFIGURATION LEVEL .................... 6
3.1 Serial Data Communication Page .................... 7
4 MODBUS PROTOCOL ............................................... 8
4.1 Introduction to Modbus Protocol ...................... 8
4.1.1
Non-volatile Memory
Limitations ........................................... 8
4.2 Modbus Function Codes .................................. 8
5 MODBUS FUNCTIONS ............................................... 9
5.1 Read Coil Status – Function Code 01 ............. 9
5.1.1
Read Coil Status Query ...................... 9
5.1.2 Read Coil Status Response ............... 9
5.2 Read Holding Register – Function Code 03 .... 9
5.2.1
Read Holding Register Query ............ 9
5.2.2 Read Holding Register Response .... 10
5.3 Force Single Coil – Function Code 05 ........... 10
5.3.1
Force Single Coil Query ................... 10
5.3.2 Force Single Coil Response ............. 10
5.4 Preset Single Register – Function Code 06 .. 11
5.4.1
Preset Single Register Query ........... 11
5.4.2 Preset Single Register Response .... 11
5.5 Loopback Test – Function Code 08 ............... 11
5.5.1
Loopback Test Query ........................ 11
5.5.2 Loopback Test Response ................. 11
5.6 Write Multiple Registers – Function Code 16 12
5.6.1
Write Multiple Registers Query ......... 12
5.6.2 Write Multiple Registers Response .. 12
6 EXCEPTION RESPONSES ...................................... 13
6.1 Examples ....................................................... 13
7 MODBUS REGISTERS ............................................. 14
7.1 Coils .......................................................... 14
7.2 Holding Registers ........................................... 16
7.3 Controller Settings/Outputs ............................ 17
7.4 Set Points ....................................................... 18
7.5 Alarm Settings ................................................ 18
7.6 Chart Settings ................................................. 19
7.7 Ramp/Soak Settings ...................................... 19
7.8 Totalizer Settings ............................................ 20
7.9 Holding Registers –
Pasteurizer Versions Only .............................. 21