CS Instruments FA 550, Instruction Manual

Page: 17 / 37

Modbus
Page 17
FA 550 V1.00
11 Modbus Register
The dew point sensor FA 550 comes with a Modbus RTU Interface.
Before commissioning of the sensor
the
communication parameters
Modbus ID, Baud rate, Parity und Stop bit
must be set in order to ensure the communication with the Modbus master.
The adjustment can be done either with the CS Instruments PC service software , DS 400 , DS
500 and the hand-held instrument PI 500 done
.
Modbus communication default values:

Modbus ID : 1 (1 -247)

Baudrate: 19200 bps (1200,2400, 4800, 9600, 19200, 38400 bps)

Parity: even (none, even, odd)

Stoppbit: 1 (1,2)
Supported are following function codes:

Function code 03: Read Holding Register

Function code 16: Write multiple Register
For parameter settings/- changing see chapter 12 Operation/Modbus Settings
11.1 Register Mapping measuring values
Modbus
Register Modbus
Address No.of
Byte
Data
Type
Description
Default
Setting
Read
Write
Unit /Comment
1001 1000 4 Float Temperature R
[°C]
1003 1002 4 Float Temperature R
[°F]
1005 1004 4 Float Relative Humidity R
[%]
1007 1006 4 Float Dew Point R
[°Ctd]
1009 1008 4 Float Dew Point R
[°Ftd]
1011 1010 4 Float Absolute Humidity R
[g/m³]
1013 1012 4 Float Absolute Humidity R
[mg/m³]
1015 1014 4 Float Humidity Grade R
[g/kg]
1017 1016 4 Float Vapor Ratio (Volume) R
[ppm]
1019 1018 4 Float Saturation vapor pressure R
[hPa]
1021 1020 4 Float Partial Vapor Pressure R
[hPa]
1023 1022 4 Float Atmospheric DewPoint R
[°Ctd]
1025 1024 4 Float Atmospheric DewPoint R
[°Ftd]
Remark for DS400 / DS 500 / Handheld devices - Modbus Sensor Datatype:
„
Data Type R4-
32“ match with „Data Type Float“