Manual
Weather Sensor u[sonic]WS7 Modbus
(16480) u[sonic]WS7 Modbus
Manual
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Modbus data protocols u[sonic]WS7 Modbus
This manual covers the general Modbus specification common to all Modbus sensors from LAMBRECHT meteo. The manual
allows easy operation of all LAMBRECHT meteo Modbus sensors. Some sensors of the Modbus family offer additional regis
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ters and functions, which are described in separate documents via the registers and functions described here. The registers
and functions described in this manual are sufficient for general operation of Modbus sensors in a weather station or PLC.
6.1 General
The Lambrecht meteo Modbus sensors follow the specification of the Modbus organization: “MODBUS APPLICATION PRO
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TOCOL SPECIFICATION V1.1b3”.
(See www.modbus.org).
6.2
Data encoding
MODBUS uses the “Big-Endian” format for addresses and data. This means that if a value is transmitted with a number format
which is larger than a single byte, that the “most significant byte” is sent first.
Example Big-Endian:
Register size value 16 - bits
0x1234 is transmitted in the sequence: 0x12 0x34.
To obtain the real measuring value, divide the received register value by the divisor (provided in 6.5, 6.6).
Values of -9999 indicate an internal sensor error.
6.3
Standard configuration - default
Baud rate:
19200 Baud
Byte frame according:
8E1 (1 start bit, 8 data bits, 1 parity bit (even parity), 1 stop bit)
RTU Sensor address:
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Default addresses of the LAMBRECHT sensors:
Address
Sensor
1
Wind speed
2
Wind direction
3
Precipitation rain[e]
4
THP
5
EOLOS IND · u[sonic]WS6
6
com[b]
7
PREOS
8
ARCO
9
u[sonic]
10
Pyranometer 2nd Class
11
Secondary standard Pyranometer
12
PT100 to Modbus converter (temperature)
13
u[sonic]WS7
6.4
Available Modbus commands
The LAMBRECHT Modbus sensors support the following commands:
• “Read Holding Register” command:
0x03 (descriptive sensor data registers)
• “Read Input Register” command:
0x04 (measured values registers)
(every measured value is to be requested individually)
• “Write Multiple Register” command:
0x10 (Write to configuration registers)
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