95
Modbus data mapping
There are two types of monitoring data: digital targets and measurands. For
convenience and efficiency, the same data can be read from different data areas.
Measurands and other 16-bit values can be read either from the IR or HR (read-
only) area and digital target values from either the DI or coil (read-only) area. It is
also possible to read the status of the DIs as packed 16-bit registers from both the IR
and the HR area.
Consequently, all monitoring data can be read as consecutive blocks of data from
the IR or HR area.
The register and bit addresses are presented in the tables below. Some register
structures are presented in separate sections below.
The HR and IR values are unsigned 16-bit integers unless otherwise
specified.
Table 5.1.15.1.-5 Mapping of Modbus data: user-defined registers
Description HR/IR address
(.bit)
DI/Coil bit
address
Writeable Value range Comment
UDR 1 1 or 385
UDR 2 2 or 386
UDR 3 3 or 387
UDR 4 4 or 388
UDR 5 5 or 389
UDR 6 6 or 390
UDR 7 7 or 391
UDR 8 8 or 392
UDR 9 9 or 393
UDR 10 10 or 394
UDR 11 11 or 395
UDR 12 12 or 396
UDR 13 13 or 397
UDR 14 14 or 398
UDR 15 15 or 399
UDR 16 16 or 400
Table 5.1.15.1.-6 Mapping of Modbus data: status registers
Description HR/IR address
(.bit)
DI/Coil bit
address
Writeable Value range Comment
Status register 1 401 IRF code See Structure 1
Status register 2 402 Warning
codes
See Structure 1
Status register 3 403 See Structure 1
Feeder Protection Relay
Technical Reference Manual - ANSI Version
REF610REF610
1MRS755535