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Table of Contents:

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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. The battery can run 2~10 years depends on the network environment and working mode.

Each LTC2 has two internal 24-bit ADC interfaces and are calibrated on 12 set resistors to make sure the accuracy measurement on wide range.

LTC2 is LoRaWAN v1.0.3 compatible. Each LTC2 is pre-load with a set of unique keys for LoRaWAN registration, register these keys to local LoRaWAN server and it will auto connect after power on.


​1.2  Features

  • LoRaWAN v1.0.3 Class A
  • max: 2 x monitor temperature channels
  • Support 3 -wire PT-100
  • 8500mAh Li-SOCI2 Battery
  • Firmware upgrade via console
  • Wall Mountable
  • Configurable via LoRa or UART
  • 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
  • Operation Temperature: -40 ~ 65 ℃


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

1.5.1  Jumper JP2 ( Power ON)

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Put a jumper on JP2 will power on the LTC2.

1.5.2  LED

The LED will flash in below case.

1.  Send an uplink packet


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:






Standard IP68 Probe Version

  • LTC2 with 1 x Standard IP68 PT100 probe.

  • Installation: Insert

  • Cable Length : 2m

  • PT100 Class : Class A

  • Probe Dimension: 4*30mm

  • Measure Range: -50 ~ 200 °C

  • Suitable Environment: General environment



Low Temperature Version

  • LTC2 with 1 x Low Temperature PT100 probe.

  • Installation: Insert

  • Cable Length : 2m

  • PT100 Class : Class A

  • Probe Dimension: 4*30mm

  • Measure Range: -196 ~ 150 °C

  • Suitable Environment: Low temperature measurement, such as COVID vaccine transport



Food Safety Version

  • LTC2 with 1 x Food Safety PT100 probe.

  • Installation: Insert

  • Cable Length : 2m

  • PT100 Class : Class A

  • Probe Dimension: 4*150mm

  • Measure Range: -50 ~ 200 °C

  • Suitable Environment: Food temperature measurement


Food Safety Version

  • LTC2 with 1 x Food Safety PT100 probe.

  • Installation: Insert

  • Cable Length : 2m

  • PT100 Class : Class A

  • Probe Dimension: 4*150mm

  • Measure Range: -50 ~ 200 °C

  • Suitable Environment: Food temperature measurement



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.

High Temperature Version

  • LTC2 with 1 x high temperature PT100 probe.
  • Installation: Insert
  • Cable Length : 3m
  • PT100 Class : Class A
  • Probe Dimension: 4*30mm
  • Measure Range: -70 ~ 550 °C

Suitable Environment: High Temperature


No Probe version:

  • User can connect to their own PT100 Probe
  • Grand Hole: M12
  • Suitable Environment:

Connect to customized probe

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. LTC2 will join the LoRaWAN network and start to transmit data. The default period for each uplink is 20 minutes.

On each uplink, LTC2 will check its two ADC Interfaces and get the temperature from the sensor and send out to server.

2.3  ​Quick guide to connect to LoRaWAN server (OTAA)

Here is an example for how to join the TTN v3 LoRaWAN Server. Below is the network structure, in this demo we use DLOS8 as LoRaWAN gateway.

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The DLOS8 is already set to connect to TTN . Rest we need to is register the LTC2 to TTN v3:Data URI imageData URI image


2.3.1  Step 1: Create a device in TTN with the OTAA keys from LTC2

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.

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.


  • 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:  ttps://


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.


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

Below is the uplink payload which shows.



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Ex1: 0x0E3C ⇒ 3644 (mV) = 3.644 V


Status & EXT


Status&ExtNot DefinedPoll Message FLAGSync time OKUnix Time RequestExt: 0b(1001)
  • Poll Message Flag:      1: This message is a poll message reply, 0: means this is a normal uplink.
  • Sync time OK:              1: Set time ok,0: N/A. After time SYNC request is send, device will set this bit to 0 until got the time stamp from application server.
  • Unix Time Request:     1: Request server downlink Unix time, 0 : N/A. In this mode, LTC2 will set this bit to 1 every 10 day to request a time SYNC. (AT+SYNCMOD to set this)
  • EXT:                               The decode method for Channel 1 data and Channel 2 data
    • 0b(0001): Upload PT100 temperature, with 2 decimals, range:  -327.67 ~ 327.67 ℃
    • 0b(0010): Upload PT100 temperature, with 1 decimals, range:  -3276.7 ~ 3276.7 ℃
    • 0b(0011): Upload Resistance instead of Temperature, range:     -327.67~ 327.67 ohm


Channel1 data and Channel 2 data



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=-50.75 ℃
  • System timestamp=0x6073E83B= 1618208827(UTC)

If payload is: EC2DH :  (EC2D & 8000 == 1) , temp = (EC2DH - 65536)/100 = -50.75 ℃

(EC2D & 8000:Judge whether the highest bit is 1, when the highest bit is 1, it is negative)

Uplink payload example 2:  0CED020203FE056073E697

  • Bat voltage:0x0CED =3309mV
  • Ext=0x02
  • Channel1 temp=0x0203/10=515.4 ℃
  • Channel2 temp=(0xFE05-65536)/10=-507.5 ℃
  • System timestamp=0x6073E697=1618208407(UTC)

If payload is: FE05H :  (FE05 & 8000 == 1) , temp = (FE05H - 65536)/100 = 507.5 ℃

(EC2D & 8000:Judge whether the highest bit is 1, when the highest bit is 1, it is negative)

Uplink payload example 3 :  0CE9032EDE1F406073E967

  • Bat voltage:0x0CE9 =3305mV
  • Ext=0x03
  • Channel1 res=0x2EDE/100=119.98 ohm
  • Channel2 res=0x1F40/100=80.00 ohm
  • System timestamp=0x6073E967= 1618209127(UTC)

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2.5  Datalog Feature

LTC2 will auto get the time from LoRaWAN server during Join, and each uplink will then include a timestamp. When user want to retrieve sensor value, user can send a poll command from the IoT platform to ask sensor to send value in the required time slot.

2.5.1  Unix TimeStamp

LTC2 uses Unix TimeStamp format based on


Users can get this time from the link: :

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 the device's time:

1. Through LoRaWAN MAC Command (Default settings)

Users need to set SYNCMOD=1 to enable sync time via the MAC command.

Once LTC2 Joined LoRaWAN network, it will send the MAC command (DeviceTimeReq) and server will reply with (DeviceTimeAns) to send the current time to LTC2. If LTC2 fails to get the time from server, LTC2 will use the internal time and wait for next time request (AT+SYNCTDC to set time request period, default is 10 days).


Note: LoRaWAN Server needs to support LoRaWAN v1.0.3(MAC v1.0.3) or higher to support this MAC command feature, Chirpstack,TTN v3 and loriot support but TTN v2 doesn't support. If server doesn't support this command, it will through away uplink packet with this command, so user will lose the packet with time request for TTN v2 if SYNCMOD=1.


2. Manually Set Time

Users need to set SYNCMOD=0 to manual time, otherwise, the user set time will be overwritten by the time set by the server.

2.5.3  Poll sensor value

Users can poll sensor values based on timestamps. Below is the downlink command.

Downlink Command to poll Open/Close status (0x31)
31Timestamp startTimestamp endUplink 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.

For example, downlink commandimage-20220620111056-7.png 

Is to check 2021/5/16 01:00:00 to 2021/5/16 02:00:00's data

Uplink Internal =10s,means LTC2 will send one packet every 10s. range 5~255s.

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.


  • 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.

For example, in US915 band, the max payload for different DR is:

  1. DR0: max is 11 bytes so one entry of data
  2. DR1: max is 53 bytes so devices will upload 4 entries of data (total 44 bytes)
  3. DR2: total payload includes 11 entries of data
  4. DR3: total payload includes 22 entries of data.

If devise doesn't have any data in the polling time. Device will uplink 11 bytes of 0    


If LTC2 has below data inside Flash:

Flash AddUnix TimeExtBAT voltageValue
8021630systime= 2021/5/16 01:17:4413684Temp1=28.89 Temp2=-327.67
8021640systime= 2021/5/16 01:37:4413681Temp1=28.79 Temp2=-327.67
8021650systime= 2021/5/16 01:57:4413681Temp1=28.67 Temp2=-327.67
8021660systime= 2021/5/16 02:17:4413684Temp1=28.60 Temp2=-327.67
8021670systime= 2021/5/16 02:37:4413684Temp1=28.56 Temp2=-327.67
8021680systime= 2021/5/16 02:57:4413684Temp1=28.52 Temp2=-327.67
8021690systime= 2021/5/16 03:17:4413684Temp1=28.51 Temp2=-327.67
80216A0systime= 2021/5/16 03:37:4413684Temp1=28.50 Temp2=-327.67
80216B0systime= 2021/5/16 03:57:4413684 Temp1=28.46 Temp2=-327.67

If user send below downlink command: 3160A06E9060A098C00A

Where : Start time: 60A06E90 = time 21/5/16 01:00:00

             Stop time: 60A098C0 = time 21/5/16 04:00:00

LTC2 will uplink this payload.



Where the first 11 bytes is for the first entry:


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)

2.6  ​Alarm Mode

LTC2 can monito the temperature in every CTTEMP time, when the temperature exceed the limit , it will uplink the sensor value immediately.

Detail commands see:


3.  Configure LTC2 via AT Command or LoRaWAN Downlink

Use can configure LTC2 via AT Command or LoRaWAN Downlink.


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.

They are same for all Dragino Device which support DLWS-005 LoRaWAN Stack. These commands can be found on the wiki: End Device AT Commands and Downlink Command


  •  Commands special design for LTC2

These commands only valid for LTC2, as below:

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3.1  Set Transmit Interval Time

Feature: Change LoRaWAN End Node Transmit Interval.

AT Command: AT+TDC

Command ExampleFunctionResponse
AT+TDC=?Show current transmit Interval

the interval is 30000ms = 30s

AT+TDC=60000Set Transmit Interval

Set transmit interval to 60000ms = 60 seconds

Downlink Command: 0x01

Format: Command Code (0x01) followed by 3 bytes time value.

If the downlink payload=0100003C, it means set the END Node's Transmit Interval to 0x00003C=60(S), while type code is 01.

  • Example 1: Downlink Payload: 0100001E           //  Set Transmit Interval (TDC) = 30 seconds
  • Example 2: Downlink Payload: 0100003C          //  Set Transmit Interval (TDC) = 60 seconds

3.2  Enable PT100 channels

Feature: Enable PT100 channels. Default only Enable Channel 1


Command ExampleFunctionResponse
AT+ENPTCHNUM=?Get current ENPTCHNUM settings



AT+ ENPTCHNUM =1Enable channel 1
AT+ ENPTCHNUM =2Enable channel 1 and 2

Downlink Command: 0xA1

Total bytes: 2 bytes


  • 0xA101: same as AT+ENPTCHNUM =1
  • 0xA102: same as AT+ENPTCHNUM =2

3.3  Set External Sensor Mode

Feature: Change External Sensor Mode.

Downlink Command: AT+EXT

Command ExampleFunctionResponse
AT+EXT=?Get current EXT settings


AT+EXT=1Set EXT to 0b(0001)
AT+EXT=2Set EXT to 0b(0010)
AT+EXT=3Set EXT to 0b(0011)

Downlink Command: 0xA2

Total bytes: 2 bytes


  • 0xA201: same as AT+EXT=1

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 ExampleFunctionResponse
AT+DISATQuit AT Commands modeOK

Downlink Command:

No downlink command for this feature.

3.5  Set system time

Feature: Set system time, unix format. See here for formmat detail.

AT Command:

Command ExampleFunction

Set System time to 2021-01-20 00:59:12

Downlink Command:

0x306007806000    // Set timestamp to 0x(6007806000),Same as AT+TIMESTAMP=1611104352

3.6  Set Time Sync Mode

Feature: Enable/Disable Sync system time via LoRaWAN MAC Command (DeviceTimeReq), LoRaWAN server must support v1.0.3 protocol to reply this command.

SYNCMOD is set to 1 by default. If user want to set a different time from LoRaWAN server, user need to set this to 0.

AT Command:

Command ExampleFunction
AT+SYNCMOD=1Enable Sync system time via LoRaWAN MAC Command (DeviceTimeReq)

Downlink Command:

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 ExampleFunction
AT+SYNCTDC=0x0ASet 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.

Downlink Command:

See Poll Sensor Value.

3.9  Enable Alarm mode

Feature: Enable Alarm Mode.

AT Command: AT_WMOD

Total bytes: 2


0xA500: AT+WMOD=0(default)

0xA501: AT+WMOD=1(alarm mode)

Downlink Command:

See Poll Sensor Value.

3.10  Alarm check time

Feature: The time interval to check sensor value for Alarm.


Total bytes: 3


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. 


Total bytes: 9  Unit: ℃






Channel 1 operating temp:10~100

Channel 2 operating temp:10~101

Downlink Command:

See Poll Sensor Value.

3.12  Set Calibrate Value

Feature: Set Calibrate value for PT100 cable.  Detail of use of this command please see connect to a customized PT100 Probe.


Total bytes: 5



Channel 1 rcable=0x0128/1000=0.296R

Channel 2 rcable=0x012C/1000=0.300R

Downlink Command:

0xA80128012C   -->  Same as AT+RCABLE=296,300

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).

AT Command: AT+PDTA

Command ExampleResponse



Print page 259 to 260


Stop Tx events when read sensor data

8021600 systime= 2021/5/16 00:17:44 1 3684 Temp1=28.71 Temp2=-327.67

8021610 systime= 2021/5/16 00:37:44 1 3685 Temp1=28.78 Temp2=-327.67

8021620 systime= 2021/5/16 00:57:44 1 3684 Temp1=28.83 Temp2=-327.67

8021630 systime= 2021/5/16 01:17:44 1 3684 Temp1=28.89 Temp2=-327.67

8021640 systime= 2021/5/16 01:37:44 1 3681 Temp1=28.79 Temp2=-327.67

8021650 systime= 2021/5/16 01:57:44 1 3681 Temp1=28.67 Temp2=-327.67

8021660 systime= 2021/5/16 02:17:44 1 3684 Temp1=28.60 Temp2=-327.67

8021670 systime= 2021/5/16 02:37:44 1 3684 Temp1=28.56 Temp2=-327.67

8021680 systime= 2021/5/16 02:57:44 1 3684 Temp1=28.52 Temp2=-327.67

8021690 systime= 2021/5/16 03:17:44 1 3684 Temp1=28.51 Temp2=-327.67

80216A0 systime= 2021/5/16 03:37:44 1 3684 Temp1=28.50 Temp2=-327.67

80216B0 systime= 2021/5/16 03:57:44 1 3684 Temp1=28.46 Temp2=-327.67

80216C0 systime= 2021/5/16 04:17:44 1 3684 Temp1=28.40 Temp2=-327.67

80216D0 systime= 2021/5/16 04:37:44 1 3683 Temp1=28.37 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


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 ExampleResponse


Print last 5 entries

Stop Tx events when read sensor data

1 systime= 2021/5/17 03:12:37 1 3681 Temp1=26.01 Temp2=-327.67

2 systime= 2021/5/17 03:17:37 1 3682 Temp1=26.02 Temp2=-327.67

3 systime= 2021/5/17 03:22:37 1 3687 Temp1=25.94 Temp2=-327.67

4 systime= 2021/5/17 03:27:37 1 3684 Temp1=25.95 Temp2=-327.67

5 systime= 2021/5/17 03:32:37 1 3684 Temp1=26.20 Temp2=-327.67

Start Tx events


Downlink Command:

No downlink commands for feature

3.16  Clear Flash Record

Feature: Clear flash storage for data log feature.


Command ExampleFunctionResponse
AT+CLRDTAClear date record

Clear all stored sensor data…

Downlink Command: 0xA3

  • Example: 0xA301     //  Same as AT+CLRDTA

4.  Battery & Power Consumption

LTC2 uses 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 Change Log and Upload Firmware


User can use ST-Link v2 to upgrade firmware into LTC2 for bug fix or new features. The hardware connection for upgrade firmware is as below:



  • ST-LINK v2 GND      <-->  LTC2 GND

  • ST-LINK v2 RESET    <-->  LTC2 NRST

  • ST-LINK v2 SWCLK  <-->  LTC2 SWCLK

  • ST-LINK v2 SWDIO  <-->  LTC2 SWDIO

  • LTC2 power must be on.  

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.


  • 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. The AT commands are disable by default and need to enter password (default: 123456) to active it. Timeout to input AT Command is 5 min, after 5-minute, user need to input password again. User can use AT+DISAT command to disable AT command before timeout.

Input password and ATZ to activate LTC2,As shown below:


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.  

Step 1You need a multimeter can measure the accuracy of 0.001 ohm. We use Agilent 34401A digit multimeter. And will do test to make sure the multimeter accuracy before the measurement. Check the shortcut resistance of the multimeter.


We know that the Multimeter has a shortcut resistance 0.002 ohm.

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 0.296R

Or use LoRaWAN downlink command (0xA8 Code) to set: 0xA801280000

User can use 0xA9 downlink command to poll the current calibration value.

Step 4Connect the PT100 to LTC2


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.

6.3  What is the frequency range of LTC2 LoRa part?

Different LTC2 version supports different frequency range, below is the table for the working frequency and recommend bands for each model:


6.4  How to change the LoRa Frequency Bands/Region

You can follow the instructions for how to upgrade image.
When downloading the images, choose the required image file for download. ​


7.  Trouble Shooting

7.1  AT Command input doesn't work

In the case if user can see the console output but can't type input to the device. Please check if you already include the ENTER while sending out the command. Some serial tool doesn't send ENTER while press the send key, user need to add ENTER in their string. 

8.  Order Info

Part Number : LTC2-XXX-YYY

XXXProbe Version

  • SI:   Standard IP68 probe x 1
  • LT:  Low Temperature probe x 1
  • HT: High Temperature probe x 1
  • FSA:  Food Safety probe x 1
  • FT:  Flat Type probe x 1
  • NA: No probe

YYYThe default frequency band

  • AS923 : LoRaWAN AS923 band
  • 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: cm
  • Device Weight: g
  • Package Size / pcs : cm
  • Weight / pcs : g

10.  ​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


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