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Table of Contents
1 GENERAL ......................................................................................................4
2 MODBUS FRAMING ......................................................................................5
2.1 Transmission Mode ..........................................................................................................................5
2.2 The RTU Frame Format ...................................................................................................................5
2.3 Address Field....................................................................................................................................5
2.4 Function Field ...................................................................................................................................5
2.5 Data Field .........................................................................................................................................5
2.6 Error Check Field..............................................................................................................................6
3 MODBUS MESSAGE FORMATS ..................................................................7
3.1 Function 03 - Read Multiple Registers..............................................................................................7
3.2 Function 04 - Read Multiple Registers..............................................................................................7
3.3 Function 06 - Write Single Register ..................................................................................................7
3.4 Function 16 - Write Multiple Registers..............................................................................................7
3.5 Function 08 - Loop-back Communications Test ...............................................................................8
3.6 Exception Responses.......................................................................................................................8
4 PROTOCOL IMPLEMENTATION ..................................................................9
4.1 Modbus Register Addresses.............................................................................................................9
4.2 Data Formats....................................................................................................................................9
4.2.1 16-bit Integer Format .................................................................................................9
4.2.2 32-bit Modulo 10000 Format....................................................................................10
4.2.3 32-bit Long Integer Format ......................................................................................10
4.3 User Assignable Registers .............................................................................................................11
4.4 Configuring and Accessing Log Files..............................................................................................12
4.5 Password Protection.......................................................................................................................12
5 POWERMETER REGISTERS DESCRIPTION.............................................13
5.1 Basic Data Registers (16-bit)..........................................................................................................13
5.2 Extended Data Registers (16/32-bit) ..............................................................................................14
5.3 Min/Max Log Registers (32-bit).......................................................................................................21
5.4 Instrument Status Registers ...........................................................................................................24
5.5 Memory Allocation Status Registers...............................................................................................26
5.6 Memory Status/Control Registers...................................................................................................27
5.7 Reset/Clear Registers ....................................................................................................................29
5.8 Basic Setup Registers ....................................................................................................................30
5.9 User Selectable Options Setup Registers.......................................................................................30
5.10 Communications Setup Registers ................................................................................................31
5.11 Analog Output Setup Registers ....................................................................................................31
5.12 Analog Expander Setup Registers................................................................................................32
5.13 Digital Inputs Allocation Registers ................................................................................................33
5.14 Timers Setup Registers ................................................................................................................34
5.15 Alarm/Event Setpoints Registers ..................................................................................................34
5.16 Pulsing Setpoints Registers..........................................................................................................38
5.17 Relay Operation Control Registers ...............................................................................................38
5.18 Pulse Counters Setup Registers...................................................................................................39
5.19 Log Memory Partitions Setup Registers .......................................................................................39
5.20 Data Log Setup Registers.............................................................................................................40
5.21 Real Time Clock Registers ...........................................................................................................41
5.22 Time Zone Information Registers .................................................................................................41
5.23 Communications Password Register ............................................................................................41
5.24 TOU System Registers Setup........................................................................................................42
5.25 TOU Daily Profiles Registers .........................................................................................................42
5.26 TOU Calendar Registers ...............................................................................................................43
5.27 TOU Calendar Years Registers .....................................................................................................44
5.28 Event Log Registers ......................................................................................................................44
5.29 Data Log Registers........................................................................................................................46
