Rejeee SL711 Water Level Sensor User Manual
- June 13, 2024
- REJEEE
Table of Contents
Rejeee SL711 Water Level Sensor User Manual
General Information
SL711 is low power water level sensor with built in LoRa module, low power cunsumption, long range, high volume Li-battery, can be widely adopted in water level monitorning situations.
Sensor Type | Model |
---|---|
Water level sensor | SL711CN, SL711EU,SL711US,SL711AS, SL711AU etc |
Note
CN: Based on LoRaWAN CN470,Frequency:470~510 MHz
EU: Based on LoRaWAN EU868,Frequency:863~870 MHz
US: Based on LoRaWAN US915,Frequency:902~928 MHz
AS: Based on LoRaWAN AS923,Frequency:920~925 MHz
Features
- 1.The maximum transmission power is 22dbm, the transmission distance is long, and the open space can reach 3-5 km.
- 2.Built in 19ah high-capacity lithium sub battery, with a service life of more than 5 years.
- 3.The new generation of water level transmitter adopted, high precision, high reliability and low power consumption.
- 4.Wireless configuration for LoRa parameters
- 5.Open communication protocol and access to the third-party Lora gateway with simple configuration.
- 6.Industrial design, working temperature range -40 ℃ ~+85 ℃.
- 7.IP67 waterproof design, suitable for harsh industrial environment.
Specifications
Parameters | Features |
---|---|
CPU | STM32L151 |
Wireless | LoRa(SX1268/SX1262) |
Encription | AES128 |
Power | Built-in Li battery(Non-rechargable) |
Battery | 19000 mAh |
**** Life span | 5 Years(Data collecting every 10 seconds,Data uploading ever |
mins@SF9)
Level Range| 0~5M
Temp Range| -40℃~125℃
Precesion| ±0.25 %FS
Response time| 10 Seconds(Configurable, e,g Data collecting time)
Communication| Half-duplex
Data rate| 300bps ~ 62.5 kbps
Working temp| -40℃~80℃
Power| Max 22dBm
Sensitivity| -140 dBm
Antenna| SMA
Frequency| SX1268: CN470SX1262: EU868 / US915 / AS923
Product Details
User Instruction
Before turn on, please make sure you connect with LoRa antenna, and battery is well installed. If the battery is empty, please change the same type Li- battery.
Turn on/off
The equipment adopts waterproof keys for easy deployment. By default, the
system will automatically enter the configured wait mode after startup, and
the timeout is 60 seconds. If the sensor receives a wireless signal within 60
seconds, the wait time is automatically reset. If there is no wireless data
for 60 seconds, it will automatically enter the normal operation mode. In this
way, it is convenient for the equipment to carry out factory production test
and parameter wireless configuration.
Indicator
The device contains a dual color (red and green) LED indicator.
Red: Indicates that the key is pressed.
Green: Indicates the sending instruction or the configuration mode.
Wireless Configuration Indicator
When turn on the device, sensor is on congifuration mode, led light is green.
Sending indicator
When the device send data, led light change from green to turn off, that means
data has been send successfully.
Wireless Configuration Mode
When turn on the device, sensor is on configuration mode, led light is green
for 60 seconds. You can use LoRa Dongle for wireless configuration, here below
you can find the instruction:
http://doc.rejeee.com/web/#/32?page_id=449
Antenna
The equipment antenna interface adopts standard SMA, with the specification of
external thread and internal hole. When installing, pay attention to avoid
metal and strong interference equipment. If the installation environment is
poor, it is recommended to use a sucker antenna with feeder for installation.
Data Uploading
When turn on the device, the sensor send data immediatly When the data is
exceeding the caliation data, the sensor send data immediatly. Sensor heart
beacon, sending data periodically
Data Configuration
You can use USB dongle for data configuration, and here is the instruction SensorTool The configutation mainly include two parts: Sensor parameter: Data sending peroid, data collecting peroid, calibration LoRa parameter: like SF, RX/TX Freq etc.
Data check peroid
The default check peroid is 10 seconds and minimum is 1 seconds, max peroid is
65553 seconds. The shorter peroid, the more sensitive the response, otherwise,
the power consumption will increase.
Data uploading peroid
The default data uploading peroid is 600 seconds(e.g 10 mins, which means
sensor heartbeacon), For example, in a constant liquid level environment, that
is, data is reported every 10 minutes, and this parameter can be adjusted
according to the actual situation.
Calibration
The default calibration is 0. For special customized projects, when reporting
the data pressure value, the user can modify the calibration value as
required. Negative values are supported, unit is Pa
Viriation
The purpose of design variation is to support the equipment to report on a
periodic basis, and to judge the variation according to the sampling period.
When the sampling data and the last sent data exceed the change amount, it is
reported immediately without waiting for the reporting cycle time. In order to
support rapid response to the measured object. The internal default minimum
change of liquid level equipment is designed as 1mA. If the system default
change is not configured (i.e. 0), the internal logic judgment is based on 1mA
as the change.
See as below:
Connect to LoRaWAN Network
SL711 water level sensor is based on standard LoRaWAN Class A/C, so you can
connect to any LoRaWAN network through OTAA or ABP. On the package of device,
you can find information as below, with this information, you can connect to
any LoRaWAN server.
Here below take TTN as an example about how to connect the device to TTN server, please make sure to choose manually and the right frequency plan as below:
Sensor | LoRaWAN |
---|---|
SL711CN | ![Configuration](https://manuals.plus/wp- |
content/uploads/2023/08/Screenshot_6-137.jpg)
SL711EU|
SL711US|
SL711AS|
Data Configuration
Normally customer only needs to configure the following information under
LoRaWAN:
- Uplink Period: Data uploading Period, that means sensor collect data and send to gateway
- Check Period: Data collecting period, that means sensor collect data but not upload
Wireless data format
The device support both LoRaWAN and non LoRaWAN.
SIP(00/01)— Non LoRaWAN
**Header| ****DevAddr| ****FCtrl| ****SeqNo| Sensor
Data1| ****…| Sensor DataN| ****CRC
---|---|---|---|---|---|---|---
1 bytes| 4 bytes| 1 bytes| 2 bytes| data 1| …| data N| 2 bytes
** Head| Device ADDR| Control| Package No.|
TLV(Refer to Type)| …| TLV(Refer to Type)| CRC16=Head Sens DataN
Sensor Data use TLV(Type+Length+Value),in order to save bandwidth and power consumption (i.e., save bytes), the length field is intentionally omitted for the basic types defined in this agreement document.
Example 03 00003DF9 00 0001 00 5F71 03 0190 FB06
e.g DevAddr is 0x00003DF9
00 5F71 device information
03 0190 sensor data(unit: 0.01mA) 0x0190 = 400 = 4mA
FB06 is CRC,refer to CRC Example
SIP(02/03)— LoRaWAN
MHDR | FHDR | F Port | FRM Payload (Sensor Data) | MIC |
---|---|---|---|---|
Data 1 | ….. | Data N | ||
TLV (Refer to specific types of sensor Data) | TLV (Refer to specific types |
of sensor Data)
FPort: 1
FRMPayload: sensor data(Massage body)
Refer to Rejeee sensor data。
Sensor Data Format
Device information(0x00)
Type | Value | Value | Value |
---|---|---|---|
1 Byte | 3 bit | 5bit | 1 Byte |
0x00 | Version | Battery Level | Reserve |
Sensor data(0x03)
Type 1 Byte | Value 2 Bytes | Note |
---|---|---|
0x03 | ADC | 2 Unsigned integer of byte, default un mV |
In order to unify the terminal firmware and adapt different range sensors, the liquid level equipment transmits and reports the actual sampling value (every 1mV is equivalent to the corresponding current value of 0.01mA)。
Feature test
Standby power
Power while trun off
Single TX power
Example: Default SF9, Transmission action current power consumption,
generally 140mA (depending on antenna matching, about 120~140mA). The test is
performed in poor days.
Simple calculation method: duration is about 0.2s, power consumption=140 * 0.2s=78uAh.
Sensitivity test
t$IP SF | 411tAltat dBm. C)BW ■ 125K, 4700111z |
---|---|
SF-7 | -126 |
SF-8 | -129 |
SF-9 | -131 |
SF=10 | -134 |
SF-11 | -136 |
SF-12 | -139 |
TX power test
CRC example
- static uint16_t get_crc16(uint16_t inData, uint16_t outData) {
- outData = (outData >> 8) | (outData << 8);
- outData ^= inData;
- outData ^= (outData & 0xff) >> 4;
- outData ^= outData << 12;
- outData ^= (outData & 0xff) << 5;
- return outData;
- }
-
- static uint16_t cal_crc16(const uint8_t *pData, const uint32_t len)
- {
- uint32_t i = 0;
- uint16_t crc16 = 0xFFFF;
- for (i = 0; i < len; i++) {
- crc16 = get_crc16(*(pData++), crc16);
- }
- return crc16; }