www.dragino.com LHT65 Temperature & Humidity Sensor User Manual Document Version: 1.1 Image Version: v1.3 Version Description Date 0.9 Draft 2019-May-14 1.0 Release 2019-Jun-15 1.
www.dragino.com 1. 2. Introduction .............................................................................................................................. 4 1.1 What is LHT65 Temperature & Humidity Sensor ........................................................................ 4 1.2 Features ...................................................................................................................................... 5 1.3 Specifications.................................................
www.dragino.com 3.2.2 3.3 4. Battery Analyze ........................................................................................................................ 25 3.3.1 Battery Type .................................................................................................................... 25 3.3.2 Power consumption Analyze .......................................................................................... 26 Sensors & Accessories ................................................
www.dragino.com 1. Introduction 1.1 What is LHT65 Temperature & Humidity Sensor The Dragino LHT65 Temperature & Humidity sensor is a Long Range LoRaWAN Sensor. It includes a built-in SHT20 Temperature & Humidity sensor and has an external sensor connector to connect to external sensors such as Temperature Sensor, Soil Moisture Sensor, Tilting Sensor etc . The LHT65 allows users to send data and reach extremely long ranges.
www.dragino.com 1.2 Features Wall mountable LoRaWAN Class A protocol Frequency Bands: CN470/EU433/KR920/US915/EU868/AS923/AU915 AT Commands to change parameters Remote configure parameters via LoRaWAN Downlink Firmware upgradable via program port Built-in 2400mAh battery for more than 10 year use. Built-in Temperature & Humidity sensor Optional External Sensors Tri-color LED to indicate status 3200 set sensor record with time stamp 1.
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www.dragino.com 2. Operation Mode 2.1 How to activate LHT65? The LHT65 has two working modes: Deep Sleep Mode: LHT-65 doesn’t have any LoRaWAN activate. This mode is used for storage and shipping to save battery life. Working Mode: In this mode, LHT65 will works as LoRaWAN Sensor mode to Join LoRaWAN network and send out the sensor data to server. Between each sampling/tx/rx periodically, LHT65 will be in STOP mode (IDLE mode), in STOP mode, device has the same power consumption as Deep Sleep mode.
www.dragino.com Assume the LG308 is already set to connect to TTN network . We need to add the LHT65 device in TTN: Step 1: Create a device in TTN with the OTAA keys from LHT65. Each LHT65 is shipped with a sticker with the default device EUI as below: User can enter these keys in the LoRaWAN Server portal. Below is TTN screen shot: Add APP EUI in the application.
www.dragino.com Step 2: Use ACT button to activate LHT65 and it will auto join to the TTN network. After join success, it will start to upload sensor data to TTN and user can see in the panel. 2.4 Uplink Payload The uplink payload includes totally 11 bytes. Uplink packets use FPORT=2 and every 10 minutes send one uplink by default. After each uplink, the BLUE LED will blink once.
www.dragino.com 2.4.1 Decoder in TTN function Decoder(bytes, port) { // Decode an uplink message from a buffer // (array) of bytes to an object of fields. var value=(bytes[0]<<8 | bytes[1]) & 0x3FFF; var batV=value/1000;//Battery,units:V value=bytes[2]<<8 | bytes[3]; if(bytes[2] & 0x80) {value |= 0xFFFF0000;} var temp_SHT=(value/100).toFixed(2);//SHT20,temperature,units:℃ value=bytes[4]<<8 | bytes[5]; var hum_SHT=(value/10).
www.dragino.com } 2.4.2 BAT-Battery Info These two bytes of BAT include the battery state and the actually voltage Bit(bit) 2 14 Value BAT Status Actually BAT level 00(b): Ultra Low ( BAT <= 2.50v) 01(b): Low (2.50v <=BAT <= 2.55v) 10(b): OK 11(b): Good (2.55v <= BAT <=2.65v) (BAT >= 2.65v) Check the battery voltage for LHT65. Bat status=(0xCBF6>>14)&0xFF=11(B)，very good battery voltage =0xCBF6&0x3FFF=0x0BF6=3062mV 2.4.3 Built-in Temperature Temperature: 0x0B0D/100=28.
www.dragino.com 2.4.4 Built-in Humidity Humidity: 0x0376/10=88.6% 2.4.5 Ext # Bytes for External Sensor: EXT # Value External Sensor Type 0x01 Sensor E1, Temperature Sensor(DS18B20) 2.4.6 Ext value DS18B20 temp=0x0ADD/100=27.81℃ The last 2 bytes of data are meaningless DS18B20 temp= (0xF54F-65536)/100=-27.
www.dragino.com 2.5 Downlink Payload After each success downlink, the PURPLE LED will blink once. Downlink Command FPort Header Downlink payload format TDC (Transmit Time Any 01 Total bytes: 4.
www.dragino.com Step 2: To configure your Application to forward data to Cayenne you will need to add an Integration.
www.dragino.com 2.7 Read stored sensor data LHT65 provides 3200 set local data storage feature, user can use AT Commands to retrieve these data for further analyze. By default, LHT65 stores one set of data every 5 minutes. LHT65 has reversed 400 sectors for storage; each sector can store 8 sets data so total 3200 sets of data can be stored. LHT65 use circle storage method, means the storage position reach the 400th sector, it will go back and erase the 1st sector and store from this position.
www.dragino.com st AT+CLRDTA: Clear the storage, record position back to 1 . AT+RTP: Set record time period, default value 5 minute (AT+RTP=5). If RTP is set to 0, LHT65 will disable the record feature ( RTP can be set by downlink command) AT+DATE=19 05 30 16 21 58 set current time to 2019-5-30 16:21:58，AT+DATE=? to check the current time. System time error is ±2 min per month. This time can be configure via downlink command. 2.
www.dragino.com Downlink: 923.3 - SF7BW500 to SF12BW500 923.9 - SF7BW500 to SF12BW500 924.5 - SF7BW500 to SF12BW500 925.1 - SF7BW500 to SF12BW500 925.7 - SF7BW500 to SF12BW500 926.3 - SF7BW500 to SF12BW500 926.9 - SF7BW500 to SF12BW500 927.5 - SF7BW500 to SF12BW500 923.3 - SF12BW500(RX2 downlink only) 2.8.3 CN470-510 (CN470) Used in China, Default use CHE=1 Uplink: 486.3 - SF7BW125 to SF12BW125 486.5 - SF7BW125 to SF12BW125 486.7 - SF7BW125 to SF12BW125 486.9 - SF7BW125 to SF12BW125 487.
www.dragino.com 917.8 - SF7BW125 to SF12BW125 918.0 - SF7BW125 to SF12BW125 918.2 - SF7BW125 to SF12BW125 Downlink: 923.3 - SF7BW500 to SF12BW500 923.9 - SF7BW500 to SF12BW500 924.5 - SF7BW500 to SF12BW500 925.1 - SF7BW500 to SF12BW500 925.7 - SF7BW500 to SF12BW500 926.3 - SF7BW500 to SF12BW500 926.9 - SF7BW500 to SF12BW500 927.5 - SF7BW500 to SF12BW500 923.3 - SF12BW500(RX2 downlink only) 2.8.5 AS920-923 & AS923-925 (AS923) Default Uplink channel: 923.2 - SF7BW125 to SF10BW125 923.
www.dragino.com 923.2 - SF10BW125 (RX2) 2.8.6 KR920-923 (KR920) Default channel: 922.1 - SF7BW125 to SF12BW125 922.3 - SF7BW125 to SF12BW125 922.5 - SF7BW125 to SF12BW125 Uplink: (OTAA mode, channel added by JoinAccept message) 922.1 - SF7BW125 to SF12BW125 922.3 - SF7BW125 to SF12BW125 922.5 - SF7BW125 to SF12BW125 922.7 - SF7BW125 to SF12BW125 922.9 - SF7BW125 to SF12BW125 923.1 - SF7BW125 to SF12BW125 923.3 - SF7BW125 to SF12BW125 Downlink: Uplink channels 1-7(RX1) 921.
www.dragino.com 3. Use AT Command 3.1 Access AT Command LHT65 supports AT Command set. User can use a USB to TTL adapter plus the Program Cable to connect to LHT65 for using AT command, as below. Connection: USB to TTL GND <--> Dupont black pin USB to TTL RXD <--> Dupont green pin USB to TTL TXD <--> Dupont white pin In PC, User needs to set serial tool(such as putty, SecureCRT) baud rate to 9600 to access to access serial console for LHT65.
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www.dragino.com AT+APPKEY: Get or Set the Application Key AT+NWKSKEY: Get or Set the Network Session Key AT+APPSKEY: Get or Set the Application Session Key AT+APPEUI: Get or Set the Application EUI AT+ADR: Get or Set the Adaptive Data Rate setting. (0: off, 1: on) AT+TXP: Get or Set the Transmit Power (0-5, MAX:0, MIN:5, according to LoRaWAN Spec) AT+DR: Get or Set the Data Rate.
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www.dragino.com 3.2 Common AT Command Sequence 3.2.1 Multi-channel ABP mode (Use with SX1301/LG308) If device has not joined network yet: 123456 AT+FDR 123456 AT+NJM=0 ATZ If device already joined network: AT+NJM=0 ATZ 3.2.2 Single-channel ABP mode (Use with LG01/LG02) Please refer this link: How to Set Single Channel Mode.
www.dragino.com 3.3 Battery Analyze 3.3.1 Battery Type LHT-65 is equipped with a 2400mAH Li-MnO2 battery. The battery is un-rechargeable battery with low discharge rate targeting for 8~10 years use. This type of battery is commonly used in IoT target for long term running, such as water meter. The discharge curve is not linear so can’t simply use percentage to show the battery level. Below is the battery performance. Minimum Working Voltage for the LHT65: LHT65: 2.45v ~ 3.
www.dragino.com 3.3.2 Power consumption Analyze Below is the transmit power consumption of the system: 1. Deep Sleep (Stop mode): a) LHT65 without sensor. ~ 3uA b) With E1 sensor: ~ 4uA 2. Sampling current while reading E1. Built-in sensor sampling time: 120ms. 2mA E1 sensor sampling time: 750ms, current: 1.5mA Above power should add 8mA CPU power in working mode. 3. LoRaWAN transmit and receive time consumption. The LoRa TX / RX time and power can be found in the LoRa calculator tool.
www.dragino.com High Power Case: Radio Parameter: SF10, 125kHz, 20dbm Transmit interval: 15 minutes. Payload : 8 Bytes. To simplify the calculation, we can: Combine built-in sensor and E1 sampling energy together to 870ms@2ma Combine two RX windows together. There is a power consumption tool for easy analyze. And below is the analyze result. Ignore the 11 year, because the battery has a max 2% discharge per year.
www.dragino.com 4. Sensors & Accessories 4.1 E1 Temperature Sensor With DS18B20 Temperature sensor with 1 meter cable long Resolution: 0.0625 °C ±0.5°C accuracy from -10°C to +85°C ±2°C accuracy from -55°C to +125°C Operating Range: -40 ~ 125 °C -55°C to 125°C Working voltage 2.
www.dragino.com 5. FAQ 5.1 How to upgrade the firmware? The LHT65 is shipped with a program cable, which is used to upload image to LHT65 for: Support new features For bug fix Change LoRaWAN bands. The latest firmware and changelog can be found at below link: http://www.dragino.com/downloads/index.
www.dragino.com Step2: Download the LHT65 Image files. http://www.dragino.com/downloads/index.php?dir=LHT65/Firmware/ Step3: click the blue global “settings” button on ST-LINK.
www.dragino.com Step4: The led on the ST-LINK adapter will now blinking, click program verify button to select the image to be upgraded.
www.dragino.com Step5: Click the start button to download the image to LHT65. *If you change different LoRa Frequency Bands/Region, you need using AT+FDR command to restore factory data after program success 5.2 How to change the LoRa Frequency Bands/Region? User can follow the introduction for how to upgrade image. When download the images, choose the required image file for download. 5.
www.dragino.com 5 6 7 8 CHE 0 1 2 3 4 5 6 7 8 908.7 910.3 911.9 913.5 908.9 910.5 912.1 913.7 909.1 910.7 912.3 913.9 909.3 910.9 912.5 914.1 909.5 911.1 912.7 914.3 909.7 911.3 912.9 914.5 909.9 911.5 913.1 914.7 910.1 911.7 913.3 914.9 Channel 32-39 Channel 40-47 Channel 48-55 Channel 56-63 915.2 916.8 918.4 920 921.6 923.2 924.8 926.4 AU915 Uplink Channels(125KHz,4/5,Unit:MHz,CHS=0) ENABLE Channel 0-63 915.4 915.6 915.8 916 916.2 916.4 916.6 Channel 0-7 917 917.2 917.4 917.6 917.8 918 918.
www.dragino.com 5.4 How to set up LHT65 to work with Single Channel Gateway such as LG01/LG02? In this case, users need to set LHT65 to work in ABP mode & transmit in only one frequency. Assume we have a LG02 working in the frequency 868400000 now, below is the step. Step1: Log in TTN, Create an ABP device in the application and input the network session key (NETSKEY), app session key (APPSKEY) from the device.
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www.dragino.com 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.
