Table Of Contents - CARLO GAVAZZI EM21 - COMMUNICATION PROTOCOL V1 REV0 Communication Protocol Manual

1.1 Introduction ...........................................................................................................................................3
1.2 MODBUS functions ...............................................................................................................................3
1.2.1 Function 03h (Read Holding Registers) ..............................................................................3
1.2.2 Function 04h (Read Input Registers) ..................................................................................4
1.2.3 Function 06h (Write Single Holding Register) .....................................................................4
1.2.4 Function 08h (Diagnostic with sub-function code 00h)........................................................5
1.2.5 Broadcast mode ..................................................................................................................5
1.3 Application notes...................................................................................................................................6
1.3.1 RS485 general considerations ............................................................................................6
1.3.2 MODBUS timing ..................................................................................................................6
2 TABLES .........................................................................................................................................7
2.1 Data format representation In Carlo Gavazzi instruments ....................................................................7
2.1.1 Geometric representation ....................................................................................................7
2.2 Maximum and minimum electrical values in EM21 ...............................................................................7
2.3 Instantaneous variables and meters .....................................................................................................8
2.4 Firmware version and revision code .....................................................................................................8
2.5 Programming lock status.......................................................................................................................8
2.6 Carlo Gavazzi Controls identification code ...........................................................................................9
2.7 Programming parameter tables.............................................................................................................9
2.7.1 Password configuration menu .............................................................................................9
2.7.2 "Application" menu...............................................................................................................9
2.7.3 System configuration menu .................................................................................................9
2.7.4 PT and CT configuration menu............................................................................................9
2.7.5 Pulse output configuration menu .......................................................................................10
2.7.6 Serial port configuration menu...........................................................................................10
2.7.7 Reset commands...............................................................................................................10
2.7.8 Note ...................................................................................................................................10
3 REVISIONS..................................................................................................................................10
Index