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BGX701-014-R03, User Manual for PT3 Transducers
Public
9.3.5 Modbus function codes
The transducer supports the function code ‘03’ to read holding registers. To read parameter values stored in
holding registers, a controller device sends a request to the slave device (transducer). This request specifies the
start register address and the number of registers to be read out. The start register is numbered from zero (for
example, 40001 = zero, 40002 =one, etc.). The transducer responds with a packet containing the values of the
registers in the range defined in the request.
9.3.5.1
Modbus mapping compatibility with different firmware versions
To read parameter values on Modbus from PT3 transducers supplied with firmware version
'TRDTB02',
you will
need to retain prefix
‘4’
in the register mapping as an input for reading parameters. For example, ‘
43018
’
9.3.6 Registers
The following register types are available in PT3:
9.3.6.1
Fixed information registers
Tabulated below are the fixed information registers available in the PT3 transducer for storing different
parameter data types:
Register address (in
decimal)
Size (in bytes)
Parameter
Format
43001
2
Modbus slave ID
Unsigned 16 bits
43002
2
Baud Rate
Unsigned 16 bits
43003
2
Stop Bits 1
Unsigned 16 bits
43004
2
Parity - NONE
Unsigned 16 bits
43005
2
MODBUS version, revision
Unsigned 16 bits
43006
2
Supported general information
register
Unsigned 16 bits
43007
2
Modbus data format
00- Hex (Not Available. For future
use)
01- 32 Bit Floating Point Format
Unsigned 16 bits
43008
2
Product type
ASCII (8 byte)
43009
2
Measuring system
Unsigned 16 bits
43010
2
Number of polls
Unsigned 16 bits
43011 to 43014
8
Transducer serial number
ASCII (8 byte)
43015 to 43018
8
Firmware name
ASCII (8 byte)
