SE02-NB -- NB-IoT Soil Moisture & EC Sensor User Manual
Table of Contents:
- 1. Introduction
- 2. Use SE02-NB to communicate with IoT Server
- 2.1 Send data to IoT server via NB-IoT network
- 2.2 Payload Types
- 2.3 Test Uplink and Change Update Interval
- 2.4 Trggier an uplink by external interrupt
- 2.5 Clock logging (Since firmware version v1.2.1)
- 2.6 Example Query saved historical records
- 2.7 Uplink log query
- 2.8 Scheduled domain name resolution
- 2.9 Set the QoS level
- 2.10 Set the downlink debugging mode(Since firmware v1.1.0)
- 2.11 Domain name resolution settings(Since firmware v1.1.0)
- 3. Configure SE02-NB
- 4. Battery & Power Consumption
- 5. Firmware update
- 6. FAQ
- 7. Order Info
- 8. Packing Info
- 9. Support
1. Introduction
1.1 What is NB-IoT Soil Moisture & EC Sensor
The Dragino SE02-NB is a NB-IoT Soil Moisture & EC Sensor for IoT of Agriculture which has 2 sensor probes. It is designed to measure the soil moisture of saline-alkali soil and loamy soil. The soil sensor uses FDR method to calculate the soil moisture with the compensation from soil temperature and conductivity. It also has been calibrated in factory for Mineral soil type.
It detects Soil Moisture, Soil Temperature and Soil Conductivity, and uploads the value via wireless to NB-IoT IoT Server.
SE02-NB supports different uplink methods including MQTT, MQTTs, UDP, TCP or CoAP for different application requirement, and support uplinks to various IoT Servers.
SE02-NB supports BLE configure and OTA update which make user easy to use.
SE02-NB is powered by 8500mAh Li-SOCI2 battery, it is designed for long-term use up to several years.
SE02-NB has optional built-in SIM card and default IoT server connection version. Which makes it works with simple configuration.
1.2 Features
- NB-IoT Bands: B1/B2/B3/B4/B5/B8/B12/B13/B17/B18/B19/B20/B25/B28/B66/B70/B85 @H-FDD
- Ultra-low power consumption
- External 2× sensor probes, probe length: 2.5m
- Monitor Soil Moisture
- Monitor Soil Temperature
- Monitor Soil Conductivity
- Multiply Sampling and one uplink
- Support Bluetooth v5.1 remote configure and update firmware
- Uplink on periodically
- Downlink to change configure
- 8500mAh Battery for long term use
- Nano SIM card slot for NB-IoT SIM
1.3 Specification
Common DC Characteristics:
- Supply Voltage: 2.5v ~ 3.6v
- Operating Temperature: -40 ~ 85°C
Soil Moisture:
- Range: 0-100.00 V/V %
- Resolution: 0.01 V/V %
- Accuracy: ±3% (0-53%)V/V %, ±5% (>53%) V/V %
- Measure Method: FDR , with temperature &EC compensate
Soil Temperature
- Range: -40.00°C ~ 85.00°C
- Resolution: 0.01°C
- Accuracy: -10°C ~ 50°C:<0.3°C, All other: <0.6°C
- Measure Method: RTD, and calibrate
Soil Conductivity
- Range: 0-20000 uS/cm(25°C)(0-20.0EC)
- Resolution: 1 uS/cm
- Accuracy: 2%FS
- Measure Method: Conductivity, with temperature compensate
NB-IoT Spec:
NB-IoT Module: BC660K-GL
Support Bands:
- B1 @H-FDD: 2100MHz
- B2 @H-FDD: 1900MHz
- B3 @H-FDD: 1800MHz
- B4 @H-FDD: 2100MHz
- B5 @H-FDD: 860MHz
- B8 @H-FDD: 900MHz
- B12 @H-FDD: 720MHz
- B13 @H-FDD: 740MHz
- B17 @H-FDD: 730MHz
- B18 @H-FDD: 870MHz
- B19 @H-FDD: 870MHz
- B20 @H-FDD: 790MHz
- B25 @H-FDD: 1900MHz
- B28 @H-FDD: 750MHz
- B66 @H-FDD: 2000MHz
- B70 @H-FDD: 2000MHz
- B85 @H-FDD: 700MHz
Battery:
- Li/SOCI2 un-chargeable battery
- Capacity: 8500mAh
- Self Discharge: <1% / Year @ 25°C
- Max continuously current: 130mA
- Max boost current: 2A, 1 second
Power Consumption
- STOP Mode: 10uA @ 3.3v
- Max transmit power: 350mA@3.3v
1.4 Applications
- Smart Agriculture
1.5 Sleep mode and working mode
Deep Sleep Mode: Sensor doesn't have any NB-IoT activate. This mode is used for storage and shipping to save battery life.
Working Mode: In this mode, Sensor will work as NB-IoT Sensor to Join NB-IoT network and send out sensor data to server. Between each sampling/tx/rx periodically, sensor will be in IDLE mode), in IDLE mode, sensor has the same power consumption as Deep Sleep mode.
1.6 Button & LEDs
| Behavior on ACT | Function | Action |
|---|---|---|
| Pressing ACT between 1s < time < 3s | Send an uplink | If sensor has already attached to NB-IoT network, sensor will send an uplink packet, blue led will blink once. |
| Pressing ACT for more than 3s | Active Device | Green led will fast blink 5 times, device will enter OTA mode for 3 seconds. And then start to attach NB-IoT network. |
| Fast press ACT 5 times. | Deactivate Device | Red led will solid on for 5 seconds. Means device is in Deep Sleep Mode. |
Note: When the device is executing a program, the buttons may become invalid. It is best to press the buttons after the device has completed the program execution.
1.7 BLE connection
SE02-NB support BLE remote configure and firmware update.
BLE can be used to configure the parameter of sensor or see the console output from sensor. BLE will be only activate on below case:
- Press button to send an uplink
- Press button to active device.
- Device Power on or reset.
If there is no activity connection on BLE in 60 seconds, sensor will shut down BLE module to enter low power mode.
1.8 Pin Definitions , Switch & SIM Direction
1.8.1 Jumper JP2
Power on Device when put this jumper.
1.8.2 BOOT MODE / SW1
1) ISP: upgrade mode, device won't have any signal in this mode. but ready for upgrade firmware. LED won't work. Firmware won't run.
2) Flash: work mode, device starts to work and send out console output for further debug
1.8.3 Reset Button
Press to reboot the device.
1.8.4 SIM Card Direction
See this link. How to insert SIM Card.
1.9 Mechanical
Main Device Dimension:
Probe Dimension:
1.10 Installation in Soil
Measurement the soil surface
Choose the proper measuring position. Avoid the probe to touch rocks or hard things. Split the surface soil according to the measured deep. Keep the measured as original density. Vertical insert the probe into the soil to be measured. Make sure not shake when inserting.
Dig a hole with diameter > 20CM.
Horizontal insert the probe to the soil and fill the hole for long term measurement.
2. Use SE02-NB to communicate with IoT Server
2.1 Send data to IoT server via NB-IoT network
The SE02-NB is equipped with a NB-IoT module, the pre-loaded firmware in SE02-NB will get environment data from sensors and send the value to local NB-IoT network via the NB-IoT module. The NB-IoT network will forward this value to IoT server via the protocol defined by SE02-NB.
Below shows the network structure:
There are two version: -GE and -1T version of SE02-NB.
GE Version: This version doesn't include SIM card or point to any IoT server. User needs to use AT Commands to configure below two steps to set SE02-NB send data to IoT server.
- Install NB-IoT SIM card and configure APN. See instruction of Attach Network.
- Set up sensor to point to IoT Server. See instruction of Configure to Connect Different Servers.
Below shows result of different server as a glance.
| Servers | Dash Board | Comments |
| Node-Red |
| |
| DataCake |
| |
| Tago.IO | ||
| General UDP | Raw Payload. Need Developer to design Dash Board | |
| General MQTT | Raw Payload. Need Developer to design Dash Board | |
| ThingSpeak |
| |
| ThingsBoard |
|
1T Version: This version has 1NCE SIM card pre-installed and configure to send value to ThingsEye. User Just need to select the sensor type in ThingsEyeand Activate SE02-NB and user will be able to see data in ThingsEye. See here for ThingsEye Config Instruction.
2.2 Payload Types
To meet different server requirement, SE02-NB supports different payload type.
Includes:
- General JSON format payload. (Type=5)
- HEX format Payload. (Type=0)
- ThingSpeak Format. (Type=1)
- ThingsBoard Format. (Type=3)
User can specify the payload type when choose the connection protocol. Example:
AT+PRO=2,0 // Use UDP Connection & hex Payload
AT+PRO=2,5 // Use UDP Connection & Json Payload
AT+PRO=3,5 // Use MQTT Connection & Json Payload
2.2.1 General Json Format(Type=5)
This is the General Json Format. As below:
{"IMEI":"863663062798914","IMSI":"460083513507314","Model":"SE02-NB","tem":21.0,"hum":19.4,"ec":7465,"tem2":20.8,"hum2":21.2,"ec2":8147,"interrupt":0,"interrupt_level":0,"battery":3.27,"signal":17,"time":"2024/11/23 01:06:52","1":[0.0,0.0,0,0.0,0.0,0,"2024/11/23 00:53:30"],"2":[0.0,0.0,0,0.0,0.0,0,"2024/11/23 00:38:30"],"3":[0.0,0.0,0,0.0,0.0,0,"2024/11/23 00:23:30"],"4":[0.0,0.0,0,0.0,0.0,0,"2024/11/23 00:08:30"],"5":[0.0,0.0,0,0.0,0.0,0,"2024/11/22 23:53:30"],"6":[0.0,0.0,0,0.0,0.0,0,"2024/11/22 23:38:30"],"7":[0.0,0.0,0,0.0,0.0,0,"2024/11/22 23:23:30"],"8":[0.0,0.0,0,0.0,0.0,0,"2024/11/22 23:08:30"]}
Notice, from above payload:
- Temperature, Humidity, Soil conductivity, Temperature 2, Humidity 2, Soil conductivity 2, Interrupt, Interrupt_level, Battery, Signal & time are the value at uplink time.
- Json entry 1 ~ 8 are the last 1 ~ 8 sampling data as specify by AT+CLOCKLOG=1,65535,15,8 Command. Each entry includes (from left to right): Soil Temperature, Soil Moisture, Soil Conductivity(EC), Soil Temperature 2, Soil Moisture 2, Soil Conductivity 2(EC) & Sampling time.
2.2.2 HEX format Payload(Type=0)
This is the HEX Format. As below:
f863663062798914f460083513507314366e0cd811010000079f08311da7084d081e1f9067412b770000000000000000000000006741278a000000000000000000000000674124060000000000000000000000006741208200000000000000000000000067411cfe0000000000000000000000006741197a000000000000000000000000674115f60000000000000000000000006741127200000000000000000000000067410eee
If we use the MQTT client to subscribe to this MQTT topic, we can see the following information when the NB sensor uplink data.
Version:
These bytes include the hardware and software version.
Higher byte: Specify Sensor Model: 0x36 for SE02-NB
Lower byte: Specify the software version: 0x82=130, means firmware version 1.3.0
BAT (Battery Info):
Ex1: 0x0CD1 = 3281mV
Signal Strength:
NB-IoT Network signal Strength.
Ex1: 0x16 = 22
0 -113dBm or less
1 -111dBm
2...30 -109dBm... -53dBm
31 -51dBm or greater
99 Not known or not detectable
Soil Moisture
Get the moisture content of the soil. The value range of the register is 0-10000(Decimal), divide this value by 100 to get the percentage of moisture in the soil.
For example, if the data you get from the register is 0x05 0xDC, the moisture content in the soil is 05DC(H) = 1500(D) /100 = 15%.
Soil Temperature
Get the temperature in the soil. The value range of the register is -4000 - +800(Decimal), divide this value by 100 to get the temperature in the soil. For example, if the data you get from the register is 0x09 0xEC, the temperature content in the soil is
Example:
If payload is 0105H: ((0x0105 & 0x8000)>>15 === 0),temp = 0105(H)/100 = 2.61 °C
If payload is FF7EH: ((FF7E & 0x8000)>>15 ===1),temp = (FF7E(H)-FFFF(H))/100 = -1.29 °C
Soil Conductivity (EC)
Obtain soluble salt concentration in soil or soluble ion concentration in liquid fertilizer or planting medium. The value range of the register is 0 - 20000(Decimal)( Can be greater than 20000).
For example, if the data you get from the register is 0x00 0xC8, the soil conductivity is 00C8(H) = 200(D) = 200 uS/cm.
Generally, the EC value of irrigation water is less than 800uS / cm.
TimeStamp:
Unit TimeStamp Example: 665eb834(H) = 1717483572(D)
Put the decimal value into this link(https://www.epochconverter.com)) to get the time.
2.2.3 ThingsBoard Payload(Type=3)
Type3 payload special design for ThingsBoard, it will also configure other default server to ThingsBoard.
{
"topic": "2276492",
"payload": {
"IMEI": "863663062798930",
"Model": "SE02-NB",
"tem": 26.0,
"hum": 47.6,
"ec": 8806,
"tem2": 26.0,
"hum2": 55.0,
"ec2": 8973,
"interrupt": 0,
"interrupt_level": 0,
"battery": 3.29,
"signal": 22,
"1": [26.0, 47.6, 8915, 26.0, 55.0, 8918, "2024/06/04 07:08:13"],
"2": [26.0, 47.6, 8933, 26.0, 55.0, 9028, "2024/06/04 07:06:13"],
"3": [26.0, 47.6, 8907, 26.0, 55.1, 8907, "2024/06/04 07:04:13"],
"4": [26.0, 47.6, 8845, 26.0, 55.0, 9044, "2024/06/04 07:02:13"],
"5": [26.0, 47.6, 8917, 26.0, 55.1, 8985, "2024/06/04 07:00:13"],
"6": [26.0, 47.5, 8883, 26.0, 55.0, 9041, "2024/06/04 06:58:13"],
"7": [26.0, 47.6, 8965, 26.0, 55.0, 8952, "2024/06/04 06:56:13"],
"8": [26.0, 47.6, 8844, 26.0, 55.0, 8994, "2024/06/04 06:54:13"]
}
}
2.2.4 ThingSpeak Payload(Type=1)
This payload meets ThingSpeak platform requirement. It includes six fields. Form 1~8 are:
Temperature, Humidity, Conduct soil, Temperature 2, Humidity 2, Conduct soil 2, Battery & Signal. This payload type only valid for ThingsSpeak Platform.
As below:
field1=Temperature value&field2=Humidity value&field3=Conduct soil value&field4=Temperature 2 value&field5=Humidity 2 value&field6=Conduct soil 2 value&field7=Battery value&field8=Signal value
2.3 Test Uplink and Change Update Interval
By default, Sensor will send uplinks every 2 hours
User can use below commands to change the uplink interval.
AT+TDC=7200 // Set Update Interval to 7200s
User can also push the button for more than 1 seconds to activate an uplink.
2.4 Trggier an uplink by external interrupt
SE02-NB has an external trigger interrupt function. Users can use the GPIO_EXIT pin to trigger the upload of data packets.
AT command:
- AT+INTMOD // Set the trigger interrupt mode
- AT+INTMOD=0 // Disable Interrupt
- AT+INTMOD=1 // Trigger by rising and falling edge
- AT+INTMOD=2 // Trigger by falling edge
- AT+INTMOD=3 // Trigger by rising edge
2.5 Clock logging (Since firmware version v1.2.1)
Sometimes when we deploy lots of end nodes in field. We want all sensors sample data at the same time, and upload these data together for analyze. In such case, we can use clock loging feature.
We can use this command to set the start time of data recording and the time interval to meet the requirements of the specific collection time of data.
- AT command: AT+CLOCKLOG=a,b,c,d
a: 0: Disable Clock logging. 1: Enable Clock Logging
b: Specify First sampling start second: range (0 ~ 3599, 65535) // Note: If parameter b is set to 65535, the log period starts after the node accesses the network and sends packets.
c: Specify the sampling interval: range (0 ~ 255 minutes)
d: How many entries should be uplink on every TDC (max 32)
Note: To disable clock recording, set the following parameters: AT+CLOCKLOG=1,65535,0,0
Example:
AT+CLOCKLOG=1,65535,1,5
After the node sends the first packet, data is recorded to the memory at intervals of 1 minute. For each TDC uplink, the uplink load will include: battery information + the last 5 memory records (payload + timestamp).
Note: Users need to synchronize the server time before configuring this command. If the server time is not synchronized before this command is configured, the command takes effect only after the node is reset.
- Downlink command: 0x0A
Format: Command Code (0x0A) followed by 5 bytes.
- Example 1: Downlink Payload: 0A01FFFF0F08 // Set SHT record time: AT+CLOCKLOG=1,65535,15,8
- Example 1: Downlink Payload: 0A0104B00F08 // Set SHT record time: AT+CLOCKLOG=1,1200,15,8
Note: When entering the downlink payload, there must be no Spaces between bytes.
2.6 Example Query saved historical records
- AT command: AT+CDP
This command can be used to search the saved history, recording up to 32 groups of data, each group of historical data contains a maximum of 100 bytes.
2.7 Uplink log query
- AT command: AT+GETLOG
This command can be used to query upstream logs of data packets.
2.8 Scheduled domain name resolution
This command is used to set up scheduled domain name resolution
AT command:
- AT+DNSTOMER=XX // Unit: hour
After setting this command, domain name resolution will be performed regularly.
2.9 Set the QoS level
This command is used to set the QoS level of MQTT.
AT command:
- AT+MQOS=xx // 0~2
Downlink command: 0x07
Format: Command Code (0x07) followed by 1 byte.
Ex1: Downlink payload: 0x0700 // AT+MQOS=0
Ex2: Downlink payload: 0x0701 // AT+MQOS=1
2.10 Set the downlink debugging mode(Since firmware v1.1.0)
Feature: Set the conversion between the standard version and 1T version downlinks.
AT command: AT+DOWNTE
| Command Example | Function/Parameters | Response/Explanation |
|---|---|---|
| AT+DOWNTE=? | Get current Settings | 0,0 (default) |
AT+DOWNTE=a,b | a: Set the conversion between the downlink of the standard version and 1T version | 0: Set the downlink of the standard version. |
| b: Enable/Disable downlink debugging | 0: Disable downlink debugging mode. |
Example:
- AT+DOWNTE=0,1 // Set to standard version downlink, and enable downlink debugging.
- AT+DOWNTE=1,1 // Set to 1T version downlink, and enable downlink debugging.
Downlink Command:
No downlink commands for feature
2.11 Domain name resolution settings(Since firmware v1.1.0)
Feature: Set dynamic domain name resolution IP.
AT command: AT+BKDNS
| Command Example | Function/Parameters | Response/Explanation |
|---|---|---|
AT+BKDNS=? | Get current Settings | 0,0,NULL (default) |
AT+BKDNS=a,b,c | a: Enable/Disable dynamic domain name resolution. | 1: Disable dynamic domain name update. The ip address will be saved after the domain name is resolved, if the next domain name resolution fails, the last saved ip address will be used. 2: Enable dynamic domain name update. The ip address will be saved after domain name resolution, if the next domain name resolution fails, the last saved ip address will be used, and the domain name resolution will be updated regularly according to the time set by the customer. |
| b: Set the time to update the domain name resolution at regular intervals. | Unit: hour | |
c: Set the IP address manually. | The format is the same as AT+SERVADDR. |
Example:
- AT+BKDNS=1,0 // Dynamic domain name resolution is disabled.
- AT+BKDNS=2,1 // The dynamic domain name resolution function is enabled and the automatic update time is set to 1 hour.
- AT+BKDNS=2,4,3.69.98.183,1883 // The dynamic domain name resolution function is enabled and the automatic update time is set to 4 hour, and manually set the ip address, if the domain name failed to resolve, it will directly use this ip to communicate. When the next domain name resolution is successful, it will be updated to the ip address of the successful resolution.
Downlink Command:
No downlink commands for feature
3. Configure SE02-NB
3.1 Configure Methods
SE02-NB supports below configure method:
- AT Command via Bluetooth Connection (Recommended): BLE Configure Instruction.
- AT Command via UART Connection : See UART Connection.
3.2 Serial Access Password
After the Bluetooth or UART connection is successful, use the Serial Access Password to enter the AT command window.
The label on the box of the node will print the initial password: AT+PIN=xxxxxx, and directly use the six-digit password to access the AT instruction window.
If you need to change the password, use AT+PWORD=xxxxxx (6 characters), NB nodes only support lowercase letters.
Note: After entering the command, you need to add a line break, and you can also set automatic line breaks in the Bluetooth tool or UART connection tool.
3.3 AT Commands Set
AT+<CMD>? : Help on <CMD>
AT+<CMD> : Run <CMD>
AT+<CMD>=<value> : Set the value
AT+<CMD>=? : Get the value
General Commands
AT : Attention
AT? : Short Help
ATZ : MCU Reset
AT+TDC : Application Data Transmission Interval
AT+CFG : Print all configurations
AT+CFGMOD : Working mode selection
AT+DEUI : Get or set the Device ID
AT+INTMOD : Set the trigger interrupt mode
AT+5VT : Set extend the time of 5V power
AT+PRO : Choose agreement
AT+RXDL : Extend the sending and receiving time
AT+DNSCFG : Get or Set DNS Server
AT+GETSENSORVALUE : Returns the current sensor measurement
AT+NOUD : Get or Set the number of data to be uploaded
AT+CDP : Read or Clear cached data
AT+SERVADDR : Server Address
MQTT Management
AT+CLIENT : Get or Set MQTT client
AT+UNAME : Get or Set MQTT Username
AT+PWD : Get or Set MQTT password
AT+PUBTOPIC : Get or Set MQTT publish topic
AT+SUBTOPIC : Get or Set MQTT subscription topic
Information
AT+FDR : Factory Data Reset
AT+PWORD : Serial Access Password
AT+LDATA : Get the last upload data
AT+CDP : Read or Clear cached data
4. Battery & Power Consumption
SE02-NB use ER26500 + SPC1520 battery pack. See below link for detail information about the battery info and how to replace.
Battery Info & Power Consumption Analyze .
5. Firmware update
User can change device firmware to::
- Update with new features.
- Fix bugs.
Firmware and changelog can be downloaded from : Firmware download link
Methods to Update Firmware:
- (Recommended way) OTA firmware update via BLE: Instruction.
- Update through UART TTL interface : Instruction.
6. FAQ
6.1 How can I access t BC660K-GL AT Commands?
User can access to BC660K-GL directly and send AT Commands.
6.2 Can I calibrate SE02-NB to different soil types?
SE02-NB is calibrated for saline-alkali soil and loamy soil. If users want to use it for other soil, they can calibrate the value in the IoT platform base on the value measured by saline-alkali soil and loamy soil. The formula can be found at this link.
6.3 How to configure the certificate?
User can can refer to this description to configure the certificate.
7. Order Info
Part Number: SE02-NB-XX
XX:
- GE: General version ( Exclude SIM card)
- 1T: with 1NCE* 10 years 500MB SIM card and Pre-configure to ThingsEye server
1NCE SIM Card NB-IoT network coverage: Austria, Belgium, Bulgaria, China, Croatia, Czech Republic, Denmark, Estonia, Finland, Germany, Great Britain, Greece, Hungary, Ireland, Italy, Latvia, Malta, Netherlands, Norway, Portugal, Puerto Rico, Russia, Slovak, Republic, Slovenia, Spain, Sweden, Switzerland, Taiwan, USA, US Virgin Islands.
8. Packing Info
Package Includes:
- SE02-NB NB-IoT Soil Moisture & EC Sensor x 1
- External antenna x 1
Dimension and weight:
- Device Size: cm
- Device Weight: g
- Package Size / pcs : cm
- Weight / pcs : g
9. Support
- Support is provided Monday to Friday, from 09:00 to 18:00 GMT+8. Due to different timezones we cannot offer live support. However, your questions will be answered as soon as possible in the before-mentioned schedule.
- Provide as much information as possible regarding your enquiry (product models, accurately describe your problem and steps to replicate it etc) and send a mail to Support@dragino.cc.