Basler Electric DGC-2020 - Manual (Page 431)

9400200990 Rev X DGC-2020 Modbus
™ Communication
i
APPENDIX B
• MODBUS™ COMMUNICATION
TABLE OF CONTENTS
APPENDIX B • Modbus™ COMMUNICATION .......................................................................................... B-1
Introduction ............................................................................................................................................ B-1
General Overview ............................................................................................................................... B-1
Intended Use of the Communications Protocol .................................................................................. B-1
Detailed Description of DGC-2020 Modbus
™ Protocol .......................................................................... B-1
Modbus ™ Protocol Overview .............................................................................................................. B-1
Device Address Field ...................................................................................................................... B-1
Function Code Field ........................................................................................................................ B-2
Data Block Field .............................................................................................................................. B-2
Error Check Field ............................................................................................................................ B-2
Serial Transmission Details ................................................................................................................ B-2
Message Framing / Timing Considerations ........................................................................................ B-2
Error Handling and Exception Responses ......................................................................................... B-2
Detailed DGC-2020 Message Definition ................................................................................................ B-2
Device Address .................................................................................................................................. B-2
Function Code and Data Block .......................................................................................................... B-2
Read Holding Registers .................................................................................................................. B-3
Return Query Data .......................................................................................................................... B-3
Preset Multiple Registers, Non-Broadcast & Broadcast ................................................................. B-4
Preset Single Register, Non-Broadcast & Broadcast ..................................................................... B-4
Data Formats ......................................................................................................................................... B-5
Short Integer Data Format (INT8) ...................................................................................................... B-5
Integer Data Format (INT16) .............................................................................................................. B-5
Long Integer Data Format (INT32) ..................................................................................................... B-6
32-bit Bit-Mapped Parameter Mapping .............................................................................................. B-6
Floating Point Data Format ................................................................................................................ B-6
Double Precision Data Format (DP) ................................................................................................... B-7
Triple Precision Data Format (TP) ..................................................................................................... B-7
Error Check ........................................................................................................................................ B-7
Interdependence of Preset Multiple Register Data ............................................................................ B-8
Mapping - DGC-2020 Parameters into Modicon Address Space .......................................................... B-8
Current Parameter Table .................................................................................................................... B-8
Breaker Management ..................................................................................................................... B-8
Bias Control Settings ...................................................................................................................... B-9
Pulse Outputs ............................................................................................................................... B-12
Bus Condition Detection ............................................................................................................... B-13
Senders ......................................................................................................................................... B-17
System Configuration and Status ................................................................................................. B-19
Control .......................................................................................................................................... B-22
Communication ............................................................................................................................. B-23
Protection ...................................................................................................................................... B-26
Alarms ........................................................................................................................................... B-32
Metering ........................................................................................................................................ B-34
Legacy Parameter Table for DGC-500 and DGC-1000 ................................................................. B-122
Legacy Parameter Table for DGC-2000 ........................................................................................ B-136
Figures
Figure B-1. 32-Bit Bit-Mapped Parameter Mapping .................................................................................. B-6
Tables
Table B-1. Exception Response Codes .................................................................................................... B-2
Table B-2. Floating Point Format ............................................................................................................... B-7