www.dragino.com LTC2 LoRaWAN Temperature Transmitter User Manual Document Version: 1.2 Image Version: v1.0 Version Description Date 1.0 Release 2021-May-17 1.1 Correct Index 2021-Jul-5 1.2 Modified the example of some errors in 2.4.
www.dragino.com 1. Introduction .............................................................................................................................. 4 1.1 What is LTC2 LoRaWAN Temperature Transmitter ..................................................................... 4 1.2 Features ...................................................................................................................................... 4 1.3 Applications ........................................................
www.dragino.com 3.7 Set Time Sync Interval .............................................................................................................. 22 3.8 Retrieve data ............................................................................................................................ 22 3.9 Enable Alarm mode .................................................................................................................. 22 3.10 Alarm check time .......................................
www.dragino.com 1. Introduction 1.1 What is LTC2 LoRaWAN Temperature Transmitter The Dragino LTC2 Industrial LoRaWAN Temperature Transmitter is designed to monitor temperature for different environment. It supports to read PT100 probe and convert the value to temperature and uplink to IoT server via LoRaWAN protocol. LTC2 supports Datalog feature. User can retrieve the sensor value via LoRaWAN downlink command. LTC2 is powered by 8500mA Li-SOCI2 battery for long time measurement.
www.dragino.com Datalog and retrieve via LoRaWAN Use pre-load PT100 probe or 3rd PT100 probe Factory calibration for different resistance range Support accuracy measure of resistance and upload Battery Monitoring and upload 1.3 Applications Logistics and Supply Chain Management Food management Cold chains solution Industrial Monitoring and Control 1.4 Hardware Change log LTC2 v1.0: Release. 1.5 Pin Definitions and Switch 1.5.
www.dragino.com 1.5.3 PT100 Interfaces There are two independent channels to connect 2 x PT100 probes. Each channel has 3-wire connection for 3-wire PT100 probes. 1.5.4 Reset Button Press this button will reboot the LTC2 1.6 Probe Variant LTC2 provide default probe version. See below for the variant: Model Photo LTC2-SI LTC2-LT Description Standard IP68 Probe Version LTC2 with 1 x Standard IP68 PT100 probe.
www.dragino.com LTC2-FT Flat Type Version LTC2 with 1 x Flat Type PT100 probe. Installation: Attached Cable Length : 2m PT100 Class : Class A Probe Dimension: 8*25mm Measure Range: -50 ~ 200 °C Suitable Environment: Attached to the measure point. LTC2-HT High Temperature Version LTC2 with 1 x high temperature PT100 probe.
www.dragino.com 2. How to use LTC2? 2.1 Connect to PT100 sensors LTC2 has different probe option provided for ordering, if user has LTC2 with probe, just skip this step. If user want to connect to a 3rd party PT100 probe, please see CONNECT A 3rd PARTY PT100 probe. 2.2 How it works? The LTC2 is working in LoRaWAN OTAA Class A mode. Each LTC2 is shipped with a worldwide unique set of OTAA and ABP keys. User needs to input the OTAA or ABP keys in the LoRaWAN network server so to register.
www.dragino.com Below is TTN screen shot: Create Application first. Manually Add a LoRaWAN End Device device. Choose OTAA and MAC v1.0.3 Input the OTAA keys for LTC2.
www.dragino.com Each LTC2 is shipped with a sticker with the default device EUI as below: Input these keys to device portal. Choose the Frequency band for this end node.
www.dragino.com Input APP Key in this page as well. Add payload formatter So TTNv3 knows how to parse the LTC2 upload value. The payload for TTN can be found at below link: https://www.dragino.
www.dragino.com 2.3.2 Step 2: Power on LTC2 LTC2 is power off when ship from factory. Put a Jumper on JP2 to power on the device. After power on, LTC2 will auto join to TTN network via the LoRaWAN coverage by DLOS8. After join success, LTC2 will start to update message to IoT server. Below is an example uplink message which shows the LTC2 is sending Join Request to TTNv3.
www.dragino.com After join successful, LTC2 will send uplink message with the sensor value. Above value shows Channel1 detect 25.94 degree. There is no PT100 connected on Channel 2, so it shows -327.67. 2.4 Uplink Payload 2.4.1 Payload Analyze Below is the uplink payload which shows Size (bytes) Value 2 1 2 2 4 BAT Status & EXT Channel 1 data Channel 2 data Unix TimeStamp BAT: Ex1: 0x0E3C ⇒ 3644 (mV) = 3.
www.dragino.com 0x1422 0x1422/100 = 51.54℃ 0x1422/10 = 515.4℃ 0x1422/100 = 51.54Ω 0xEC2D (0xEC2D-65536)/100 (0xEC2D-65536)/10 0xEC2D/100 = -50.75 ℃ = -507.5 ℃ = 604.61Ω Unix TimeStamp Refer to Datalog feature. Example Uplink Payload: Uplink payload example 1:0CE9011422EC2D6073E83B Bat voltage:0x0CE9 =3305mV Ext=0x01 Channel1 temp=0x1422/100=51.54 ℃ Channel2 temp=(0xEC2D-65536)/100=-50.
www.dragino.com User can get this time from link: https://www.epochconverter.com/ : Below is the converter example So, we can use AT+TIMESTAMP=1611889405 or downlink 3060137afd00 to set current time 2021 – Jan -- 29 Friday 03:03:25 2.5.2 Set Device Time There are two ways to set device’s time: 1. Through LoRaWAN MAC Command (Default settings) User need to set SYNCMOD=1 to enable sync time via MAC command.
www.dragino.com 2.5.3 Poll sensor value User can poll sensor value base on timestamps from server. Below is the downlink command. 1byte 4bytes 4bytes 1byte 31 Timestamp start Timestamp end Uplink Interval Timestamp start and Timestamp end use Unix TimeStamp format as mentioned above. Devices will reply with all data log during this time period, use the uplink interval.
www.dragino.com 2.5.4 Datalog Uplink payload When server senser a datalog polling to LTC2, LTC2 will reply with one or more uplink messages as reply. Each uplink message includes multiply data entries value. Each entry has the same payload format as normal uplink payload. Note: Poll Message Flag is set to 1. Each data entry is 11 bytes, to save airtime and battery, devices will send max bytes according to the current DR and Frequency bands.
www.dragino.com 0E64410B49800160A072B80E61410B3F800160A077680E61410B33800160A07C180E64410B2C8 00160A080C80E64410B28800160A085780E64410B24800160A08A280E64410B23800160A08ED 80E64410B22800160A093880E64410B1E800160A09838 Where the first 11 bytes is for the first entry: 0E64410B49800160A072B8 Bat voltage:0x0E64 =3684mV poll message flag & Ext=0x41,means reply data,Ext=1 Channel1 temp=0x0B49/100=28.89℃ Channel2 temp=0x8001/100=-327.67℃ System timestamp=0x60A072B8= 1621127864(UTC) 2.
www.dragino.com 3. Configure LTC2 via AT Command or LoRaWAN Downlink Use can configure LTC2 via AT Command or LoRaWAN Downlink. AT Command Connection: See FAQ. LoRaWAN Downlink instruction for different platforms: http://wiki.dragino.com/index.php?title=Main_Page#Use_Note_for_Server There are two kinds of commands to configure LTC2, they are: General Commands. These commands are to configure: General system settings like: uplink interval. LoRaWAN protocol & radio related command.
www.dragino.com Feature: Enable PT100 channels. Default only Enable Channel 1 AT Command: AT+ENPTCHNUM Command Example Function AT+ENPTCHNUM=? Get current ENPTCHNUM settings Response 1 OK AT+ ENPTCHNUM =1 Enable channel 1 AT+ ENPTCHNUM =2 Enable channel 1 and 2 Downlink Command: 0xA1 Total bytes: 2 bytes Example: 0xA101: same as AT+ENPTCHNUM =1 0xA102: same as AT+ENPTCHNUM =2 3.3 Set External Sensor Mode Feature: Change External Sensor Mode.
www.dragino.com 3.4 Quit AT Command Feature: Quit AT Command mode, so user need to input password again before use AT Commands. AT Command: AT+DISAT Command Example Function Response AT+DISAT Quit AT Commands mode OK Downlink Command: No downlink command for this feature. 3.5 Set system time Feature: Set system time, unix format. See here for formmat detail.
www.dragino.com 0x28 01 // Same As AT+SYNCMOD=1 0x28 00 // Same As AT+SYNCMOD=0 3.7 Set Time Sync Interval Feature: Define System time sync interval. SYNCTDC default value: 10 days. AT Command: Command Example Function AT+SYNCTDC=0x0A Set SYNCTDC to 10 (0x0A), so the sync time is 10 days. Downlink Command: 0x29 0A // Same as AT+SYNCTDC=0x0A 3.8 Retrieve data Feature: Retrieval data for specify time slot. AT Command: No AT Command, only valid for downlink command.
www.dragino.com AT+CITEMP: Total bytes: 3 Example: 0xA60001:AT+CITEMP=1(default) Set collection interval in 1min,only in alarm mode Downlink Command: See Poll Sensor Value. 3.11 Set Alarm Threshold Feature: Set Alarm Threshold. AT Command: Total bytes: 9 Unit: ℃ Example: A7FF380320FF380320 AT+ARTEMP=-200,800,-200,800 A7000A0064000A0065 AT+ARTEMP=10,100,10,101 Channel 1 operating temp:10~100 Channel 2 operating temp:10~101 Downlink Command: See Poll Sensor Value. 3.
www.dragino.com 3.13 Poll Calibrate Value Feature: Poll Calibrate value. LTC2 will reply with this command send an uplink to server. AT Command: No AT Command. Downlink Command: Example:A901 End nodes will send racable config to server Like uplink payload: 010128012C 3.14 Print data entries base on page. Feature: Print the sector data from start page to stop page (max is 400 pages).
www.dragino.com Temp2=-327.67 80216E0 systime= 2021/5/16 04:57:44 1 3684 Temp1=28.36 Temp2=-327.67 80216F0 systime= 2021/5/16 05:17:44 1 3685 Temp1=28.32 Temp2=-327.67 Start Tx events OK Downlink Command: No downlink commands for feature 3.15 Print last few data entries. Feature: Print the last few data entries AT Command: AT+PLDTA Command Example AT+PLDTA=5 Print last 5 entries Response Stop Tx events when read sensor data 1 systime= 2021/5/17 03:12:37 1 3681 Temp1=26.01 Temp2=-327.
www.dragino.com 4. Battery & How to replace 4.1 Battery Type LTC2 is equipped with a 8500mAH ER26500 Li-SOCI2 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 LTC2: LTC2: 3.0v ~ 3.6v 4.
www.dragino.com Step 1: Downlink the up-to-date DRAGINO_Battery_Life_Prediction_Table.xlsx from: https://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/Battery_Analyze/ Step 2: Open it and choose Product Model Uplink Interval Working Mode And the Life expectation in difference case will be shown on the right. 5. Firmware Change Log and Upload Firmware User can use ST-Link v2 to upgrade firmware into LTC2 for bug fix or new features.
www.dragino.com 6. FAQ 6.1 How to use AT Command to configure LTC2 LTC2 supports AT Command set. User can use a USB to TTL adapter plus the Program Cable to connect to LTC2 for using AT command, as below. Connection: USB to TTL GND <--> LTC2 GND USB to TTL RXD <--> LTC2 TXD USB to TTL TXD <--> LTC2 RXD In PC, User needs to set serial tool(such as putty, SecureCRT) baud rate to 9600 to access to access serial console for LTC2.
www.dragino.com 6.2 How to connect a customized PT100 cable? The LTC2 has two channels means it can connect 2 x PT100 cables. Besides use the PT100 cables provided by Dragino, User can connect their PT100 probes. When connect to a user PT100 probe, we recommend that user do a calibration to eliminate the effect from the cables so to get the best accuracy. Below is the step for calibrate on a three wire PT100 probes. There is no step for 2 wire probe calibration at the moment.
www.dragino.com Step 2: Measure the resistance between the two shorted wires of PT100 Probe. ‘; As example, in this step, we check the shorted wire (both red) with 0.594 ohm, So we know that each wire of PT100 has (0.594-0.002)/2=0.296R (Where 0.002 is the value we got from step 1) . Step 3: Run Calibrate Command. Run this command to both channels to use 0.296R calibrate resistance. AT+RCABLE=296,0 --> Calibrate Channel 1 with 0.
www.dragino.com For a 3 wire PT100, there are two wire are shortcut, for example, as per above photo Channel 1, there are two red wire , which are shortcut in PT100, connect them as the photo. The 3rd wire (white wire ) connect to the left pin of Channel -1. 6.
www.dragino.com AU915: LoRaWAN AU915 band EU433: LoRaWAN EU433 band EU868: LoRaWAN EU868 band KR920: LoRaWAN KR920 band US915: LoRaWAN US915 band IN865: LoRaWAN IN865 band CN470: LoRaWAN CN470 band 9. Packing Info Package Includes: LTC2 LoRaWAN Temperature Transmitter x 1 Dimension and weight: Device Size: Device Weight: Package Size: Packege Weight: 10. Support Support is provided Monday to Friday, from 09:00 to 18:00 GMT+8.
