Q: What model is the EM300 temperature and humidity chip?

EM300 series uses Sensirion SHT30 chip.


Q: What is temperature and humidity detection range of EM300 series?

One sensor can only measure a single point, so it's important to locate the sensor by identifying your goals and space conditions. If the space air is uniform, one sensor is enough. If there are some factors causing conditions to vary widely, like heat source or strong air flows, you can add more sensors. You can add more sensors to where you are focusing on, too.


Q: What is the response time if EM300 series is in a place where temperature difference is large?

Since EM300 series uses IP67 case, it will take some times to allow the air flow into the vent to detect the real-time temperature. As our research, it will take about 1 hour to sync the temperature if the difference is large.


Q: Can EM300-ZLD/SLD measure oil or other liquids?

EM300-ZLD/SLD detects the liquid leakage based on liquid conductive principle so it can detect the water (pure water is not included), weak acid or weak base liquids. Oil is non-conductive and can not be detected by EM300-ZLD/SLD. For strong corrosive liquids, please contact Milesight to customize other types of cables.


Q: Can the detection condition of EM300-ZLD/SLD be set more sensitive like 3 mm?

Not support, EM300-ZLD/SLD detects the liquid based on conductive principle and 5 mm is the condition to ensure the trigger, this can not be set by software.


Q: Can EM300-ZLD/SLD detect the location of leakage?

No, EM300-ZLD/SLD can only detect whether the liquid is leaked.


Q: Is EM300-ZLD/SLD cable extendable?

Yes, please contact Milesight if you need to customize longer cables.


Q: Can I buy a longer water cable and connect to EM300-ZLD on my own? Will the longer cable affect the detection speed?

Yes, you can buy a longer cable on your own and the long cable will not affect the detection speed.


Q: How to fix the magnet parts of EM300-MCS to the door?

The magnet parts can be fixed by screws.


Q: Can EM300-MCS count the door open and close times?

Not support, EM300-MCS can only upload the open or close status. It is suggested to add the counter on your platform to calculate the open or close times.


Q: Will the water leakage status of EM300-ZLD/SLD or door status of EM300-MCS upload according to reporting interval or upload when status changes?

Both support. EM300 series will not only upload water leakage status or door status regularly but also upload data immediately when status changes.


Q: While EM300-DI only supports reed switch pulse meter, how to connect the meter with voltage pulse output?

For this kind of meter please select UC300 which DI supports 3-24 VDC pulse outputs.


Q: What is the maximum pulse frequency EM300-DI support?

The maximum frequency is 2kHz.


Q: What is the sampling/collecting interval of temperature and humidity sensor?

The sampling/collecting interval is 10 minutes, you can change it when you enable the threshold setting.


Q: What is the vent under the EM300 series device used for? Will it affect the waterproof and dustproof?

The vent is used for air ventilation and temperature/humidity measurement, it will not affect the waterproof and dustproof results.


Q: Can EM300 series support UV-proof?

Yes, the material of EM300 is ABS + PC which supports UV-proof.



Q: Why can not receive EM300 device battery level data on regular uplinks?

The reporting interval of EM300 battery level is 6 hours and this is non-editable.


Q: Does this device support low battery alarm?

Yes, the device will send a low battery alarm packet to network server when battery level is lower to 10%.


Q: Can the device send any alarm message (Email, SMS, etc.) when threshold is triggered?

No, but it will send threshold alarm packet to network server right away. You can connect the device to Milesight IoT Cloud which support Email alarm or mobile App pushment, or connect to other IoT platforms which support alarm notification services.


Q: How to configure the device to work with Milesight D2D?

Please refer to article How to Use Milesight D2D Featuring LoRa on Milesight Nodes for details.


Q: Can the device work with other brand gateways?

Yes, the device can work with other brand gateways which supports standard LoRaWAN protocol.


Q: How the device achieve secure communication with gateway?

The device communicate with gateway via LoRaWAN protocol which support AES128 encryption and a series of communication mechanism, for details please refer to article:


Q: What is the default App EUI and AppKey? Can the device support random AppKeys?

The default App EUI is 24E124C0002A0001 and Appkey is 5572404C696E6B4C6F52613230313823.

Yes, the device support random Appkey pre-configuration and you can ask Milesight for it before purchase.


Q: Are device EUI, App EUI and Appkey editable on your device?

The device EUI is unique and non-editable, App EUI and Appkey can be edited via ToolBox.


Q: How to connect device to network servers like TTN, Chirpstack, Actility, Senet, etc?

Yes, please refer to Milesight IoT knowledge base:


Q: How to decode the data? Where can I find the decoder?

For the definition of data please refer to corresponding device user guides:

Milesight also provides decoder examples here: You can modify these decoders according to your platform requirements.


Q: Why there is decode error even I use the decoder example provided by Milesight?

Please change your device LoRaWAN version to V1.0.2 or V1.0.3 and check again.


Q: What reporting interval can the device be configured?

1 to 1080 minutes is configurable. It's not suggested to shorten the interval to second which will reduce the battery life quickly.


Q: What is the working mechanism of rejoin mode feature?

The device will send a specific number of LinkCheckReq MAC packets to the network server every 30 mins or longer to validate connectivity; If there is no response after the specific number of packets , the device will re-join the network.


Q: Can the device get confirmation to know if the data is sent to server?

Yes, please enable Confirmed Mode on ToolBox. If the device does not receive the confirmation, it will send the data once again.


Partial support, please refer to corresponding user guide for downlink commands:


Q: How to use data retransmission feature? Can device retransmission data if it loses power supply suddently?

Please refer to article How to Use Data Retransmission Function on Milesight Sensors. This feature can not work with sudden changes of sensor itself like losing power supply or changing LoRaWAN parameters, it can work when losing connections with gateway or server for some times.


Q: How to distinguish periodic report and retransmission historical data? Is there unique sequence number or timestamp to with each retransmission?

The reported format between periodic report and re-transmission data is different, and each re-transmission packet includes timestamp. For packet format details please refer to corresponding user guide.


System & Maintenance

Q: Can the device upgrade remotely via LoRaWAN?

Not support, Milesight only provides locally upgrade via Milesight ToolBox App or ToolBox PC software now.


Q: Where to find the latest firmware of devices?

Please find the latest firmwares here:


Q: Can I backup the configurations of one device and import to another device?

Yes, both Milesight ToolBox App and software supports backup feature, this should ensure both devices have the same model and frequency.


Q: Can all default parameters of pre-configured before shipping?

Yes, Milesight provide OEM services to pre-configure the device settings before shipping to save your time to configure bulk of devices.


Q: Can Milesight provide code to modify the firmware?

No, the device does not support firmware modification by yourselves. If you have any extra feature requirements, please contact Milesight for software customization services.


Q: Does the device have any API to get the data?

No, the device can only send data to gateway via LoRaWAN. It's suggested to connect device to Milesight gateway which provides MQTT/HTTP API to send data to your applications.


Q: How to get device debug logs for troubleshooting?

Please refer to article How to Get Milesight Node Log File.


Q: Can the device store the data locally?

Yes, EM300-TH/MCS/SLD/ZLD (hardware version 3.x) supports storing about 2000 pieces of data, please upgrade firmware to version 1.5 and later. EM300-DI (all hardware versions) supports data storage.


Q: How to export the data stored in EM300 series? What is the export format?

Please use Milesight ToolBox App or PC software to export the data as csv file.