Product manual
SPECIFICATION
product name： | Integrated transmitter for soil temperature, humidity, and salinity |
Model： | WLS-06-SL |
version： | V1.0 |
Creator： | He Genwen |
reviewed by： | Yuan Chao |
1、brief introduction
The S-THEC-R-A-L2000 integrated sensor for soil temperature, humidity, and salinity adopts a high-precision digital sensing chip combined with embedded processing and calculation to collect and measure the temperature, humidity, and conductivity (EC) of soil. It has the characteristics of high sensitivity, accurate measurement, stable operation, low power consumption, good weather resistance, and easy use, and can be widely used in industries such as agriculture, forestry, horticulture, and planting.
Each sensor undergoes temperature coefficient calibration and soil moisture accuracy calibration before leaving the factory, ensuring that users can directly collect data during application. The sensor is based on RS-485 serial bus standard communication and has strong anti-interference ability.
1. Functional characteristics
1) Adopting independently developed RF resonant circuit, stable signal and strong penetration power
2) Embedded moisture and conductivity models and compensation calculations for different soils with high accuracy
3) Wide measurement range, good linearity, and wide applicability
4) Built in memory, no maintenance or on-site calibration required
5) Energy saving and power-saving mode support can meet the demanding power consumption requirements in low-power measurement scenarios
6) Completely sealed, resistant to acid and alkali corrosion, can be buried in soil or directly immersed in water for long-term dynamic testing
2.Specification
Soil temperature measurement |
Typical accuracy: 0.5 ℃
High precision range: 0-50 ℃ Resolution: 0.1 ℃ Range: -40 ℃ -85 ℃ |
Measurement of soil moisture content | Typical accuracy：3% resolution ratio：0.1% range：0-100% |
Conductivity and salinity measurement | Typical accuracy：3% resolution ratio：0.01 mS/cm range：0-655.35 mS/cm |
Working temperature range | -40℃-85℃ |
Collection time | < 0.2 秒 |
consumption | average current:7.0mA@12V peak current:9.5mA@12V |
Supply Voltage | DC 8-28V |
interface | RS485(MODBUS agreement) |
Wire length | Default 2 meters(customizable) |
Product size | 72*45*15mm(housing)，65mm (Steel needle length) |
2、Interface Description
Connect the sensor according to the instructions in the wiring diagram in Figure 1, then insert the sensor probe pins into the soil to be measured, connect the power, and obtain the soil temperature, soil humidity, and soil salinity values at the measurement point.
Figure 1 Sensor Wiring Diagram (Dimensional Tolerance: ± 1.0mm)
3、communication protocol
1.Basic communication parameters
Data bits | 8 digits |
Parity bit | not have |
stop bit | 1 digit |
Check Code | 16 bit CRC verification code |
BAUD | 9600bps |
2. Definition of data frame format
Using Modbus RTU communication protocol, the format is as follows:
Address code=1 byte
Function code=1 byte
Data area=N bytes
Error check=16 bit CRC code (low byte first)
Address Code: The address code is the address of the sensor and is unique in the communication network (factory default is 0x01).
Function code: Instruction function indication issued by the host, function code 0x03 reads register data, and function code 0x06 writes to a single register. Data area: The data area is specific communication data, please note that the high byte of 16 bits data comes first. CRC code: Two byte checksum, with low bytes before and high bytes after.
Host inquiry frame structure
Address code | function code | Register Start Address | register length | Check code low bit | Check code high bit |
1 byte | 1 byte | 2 byte | 2 byte | 1 byte | 1 byte |
Slave response frame structure
Address code | function code | Effective Bytes | data area | Check code low bit | Check code high bit |
1 byte | 1 byte | 1 byte | …… | 1 byte | 1 byte |
3.Register data
Register Start Address | The unit of data length is 2Bytes | content | illustrate | operate |
0000H-0001H | 2 |
| reserve |
|
0002H | 1 | 485 node address | Unsigned integer, 1-252 | Reading and writing |
0003H-0009H | 7 |
| reserve |
|
000AH | 1 | Oscillation count value | Unsigned integer, 0-65535 | read only |
000BH | 1 | temperature | Signed number (increased by 10 times), -40.0~100.0℃ | read only |
000CH | 1 | temperature | Unsigned percentage, resolution 0.1% (increased by 10 times) | read only |
000DH | 1 | Soil salt score | Unsigned number, resolution 0.01mS/cm | read only |
4. Communication protocol examples and explanations
4.1. Read the inquiry frame for soil temperature, soil humidity, and soil salinity values at sensor address 0x01
Example: 01 03 00 0B 00 03 74 09 Queries 4-word (8 Byte) data from node 1 with a starting address of 0x000B
Address code | function code | start address | The unit of data length is 2Byte | Check code low bit | Check code high bit |
0x01 | 0x03 | 0x00 0x0B | 0x00 0x03 | 0x74 | 0x09 |
Response frame (e.g. reading a temperature of -10.1 ℃, soil humidity of 15.5%, and soil salinity value of 1mS/cm)
Address code | function code | Effective Bytes | Temperature value | soil moisture | Soil salt score | Check code low bit | Check code high bit |
0x01 | 0x03 | 0x06 | 0xFF 0x9B | 0x00 0x9B | 0x00 0x64 | 0x20 | 0xA2 |
pour：
1) Temperature: When the temperature is below 0 ℃, upload 0xFF9B (hexadecimal) as a complement=-101=>Temperature=-10.1 ℃
2) Soil moisture: unsigned number
0x009B (hexadecimal)=155=>Soil moisture=15.5%
3) Soil salt score: unsigned number
0x0064 (hexadecimal)=100=>Soil salt score=1mS/cm
4.2. Modifying Sensor Address
Example: Changing address 01 to address 02
Note: When modifying the address, only one sensor can be connected to the bus, and the starting address is always 0x00 0x02
Set Frame
Address code | function code | start address | New sensor address | Check code low bit | Check code high bit |
0xFE | 0x06 | 0x00 0x02 | 0x00 0x02 | 0xBD | 0xC4 |
Reply frame
Address code | function code | start address | New sensor address | Check code low bit | Check code high bit |
0xFE | 0x06 | 0x00 0x02 | 0x00 0x02 | 0xA9 | 0xF8 |
4、matters needing attention
1. Please check if the packaging is intact and verify if the product model matches the selection.
2. Do not connect wires with electricity. Only after the wiring is completed and checked for accuracy can it be powered on.
3. Do not arbitrarily modify the components or wires that have been soldered before the product leaves the factory. If there is a need for modification, please contact the manufacturer.
4. Sensors belong to precision devices. Users should not disassemble them themselves or use sharp objects or corrosive liquids to contact the surface of the sensor to avoid damaging the product.
5. The soil to be tested should not contain metal substances as much as possible, otherwise it may cause deviation in the test data.
