Wireless Environmental Sensor Product Manual



  • Industrial Grade Environment Sensor with Temperature, Pressure, Humidity, Gas Resistance and Indoor Air Quality output
  • Operating Temperature Range -40 to +85 °C
  • Operating Pressure Range 300 to 1100% hPa
  • Operating Humidity Range 0 to 100% r.H.
  • Gas Resistance output in ohms
  • Inbuilt Indoor Air Quality Metric Calculation, Range 0-100
  • Configurable Heater Temperature and Duration for Gas Resistance measurement
  • 1-Mile Range with 2.4GHz or 2 Mile Range with 900MHz On-Board Antenna
  • Superior LOS Range of up to 28 miles with 900MHz High-Gain Antennas
  • Interface to Raspberry Pi, Microsoft Azure, Arduino and More
  • Example Software for Visual Studio and LabVIEW
  • Wireless Mesh Networking using DigiMesh®
  • Up to 256 Sensor Nodes per Network
  • Open Communication Protocol for custom interfacing applications
  • Small Form Factor (3×3 inch)
  • Multiple Modes of Operation (Configuration and Run mode)
  • Wireless Sensor and Radio Configuration feature
  • Default Factory setting Restore option
  • Power Efficient Built-in Sleep mode
  • User Configurable Sleep duration
  • Up to 500,000 Transmissions from 2 AA Batteries
  • Reliable Transmission incorporating packet Retries
  • Secure Transmission using AES-128 Encryption
  • Real time battery status


  • Long Endurance Industrial Automation
  • Indoor Air Quality
  • Home Automation and Control
  • Component of a IoT system
  • Wireless Navigation
  • Weather Forecast at remote locations


Introducing NCD’s Wireless Environment Sensor, boasting up to a 28 Mile range using a 900MHz wireless mesh networking architecture or 1 Mile using 2.4GHz wireless mesh networking architecture. Incorporating a BOSCH BME680 sensor, it samples and processes temperature, pressure, humidity and gas resistance and transmits this information to user defined receiver(s). The whole process is repeated at user defined intervals. For technical details, please refer to the BME680 datasheet.

Powered by just 2 AA batteries and an operational lifetime of 300,000 wireless transmissions, a 3 years battery life can be expected depending on environmental conditions and the data transmission interval. Optionally, this sensor may be externally powered.

With an open communication protocol this sensor can be integrated with just about any control system or gateway. Data can be transmitted to a PC, a Raspberry Pi, to Microsoft Azure® IoT, or Arduino. Sensor parameters and wireless transmission settings can be changed on the go using the open communication protocol providing maximum configuration depending on the intended application.

The range, price, accuracy, battery life and security features of Wireless Environmental Sensor makes it an affordable choice which exceeds the requirements for most of the Industrial as well as consumer market applications.

To complete a network with an industrial sensor at one end, a Zigmo/Router is required at the receiving end (PC end) that receives data from sensor. A set of sensor and Zigmo is shown in following figure.

outdoor air quality sensor
Sensor with Zigmo/Router

Indoor Air Quality (IAQ) Measurement Description

The Wireless Environment Sensor features inbuilt algorithm for processing measured gas resistance, humidity and temperature and generating Indoor Air Quality(IAQ) metric. There is no standard procedure to convert gas resistance to IAQ, hence NCD uses algorithm developed in-house to generate IAQ metric that ranges between 0 to 100. The Indoor air quality can be classified with respect to the IAQ using the following illustration.

As discussed above, the sensor sleeps for most of the time to conserve battery and only wakes up at user defined intervals. The gas resistance output from the sensor varies if the delay between the readings (sleep time) is varied. Hence, it is impossible in this scenario to calculate a standard IAQ value that ranges between 0 and 100. In order to provide consistent IAQ output, the minimum sleep delay that can be set for the Wireless Environment Sensor is 24 seconds.The sensor accepts any delay value from the user in configuration mode but rounds it to nearest 24 second multiple. Furthermore, the sensor requires 30 minutes for warming up. During this period the IAQ output remains 0. Depending upon the sleep delay set by the user, there can be one or multiple frames sent from the sensor that may contain a 0 IAQ Value.

The IAQ Value returned is a relative IAQ with respect to the average reading at the end of the warm up period. The air quality during the warmup period is taken as a reference and further IAQ readings will show quality relative to that air quality. After the warm up period, the current air quality is taken as baseline and the IAQ is considered to be at the middle of the average air quality range. An improvement or degradation from this quality of air is then reflected as change in IAQ reading.


Getting Started

The Vibration Sensor  and Zigmo/Router come pre-programmed and work out of the box. In this section we will setup a sensor and Zigmo link and start receiving data on our PC. Though this guide shows how to visualize data on LabVIEW utility, you can also use a simple serial terminal to see raw data by following these steps.

Resources Required

Note: The Wireless Sensor comes with external power enabled, for battery conservation during shipping. To enable battery power, open the enclosure and set the PS (power select) jumper which is parallel to the marking line on the board.


  1.  Power-up the Wireless Sensor and make sure its antenna is installed
  2. Connect your Zigmo/Router to your PC
Figure 1: Connect Zigmo/Router to PC
  1. Identify the serial port allocated to it by going into device manager (You can also find the serial port using Digi provided utility XCTU)
At this stage, both the Sensor and Zigmo have automatically established communication and the data can be read from the serial port at which Zigmo has been installed.
Figure 2: Serial port identification
  1. Install the LabVIEW utility for the sensor you are working with. Run this utility.
  2. Press the port configure button and select the PORT you identified in step 3. Select baud rate of 115200 and press OK.
Figure 3: LabVIEW Utility for Sensor
  1. Press the Run button to visualize incoming data.

If you were not able to communicate after completing the above steps then there might be a fault at either end of the communication network. Please refer to the troubleshooting section for identifying and resolving some common issues. If you are still not able to communicate after troubleshooting then please contact us at any time.

Figure 4: LabVIEW Utility for sensor showing incoming data


Changed/Unknown setting at sensor end

One of the issues for unsuccessful communication can be a changed setting at the sensor end due to which the sensor and Zigmo are unable to establish a connection. You can resolve this problem by going back to the factory default settings which are provided in Table 1. Please refer to Figure 7 and follow steps shown in it for applying factory default settings.

Once the sensor resets it will start sending a frame every 600 seconds after factory reset.

Please refer to the detailed document available to Digi website to understand X-bee communication parameters and its operation mechanism.

Table 1: Default Parameters programmed after Factory reset sequence

Changed/Unknown setting at PC end

Sometimes a changed setting at Zigmo end, whether intentional or unintentional, can cause a network failure and no data reception at PC end. To fix this issue when the sensor end is operating at factory default settings you will have to bring the Zigmo/Router to factory default settings as well. For that, please download the configuration file for Zigmo from our website. You will also require XCTU utility provided by Digi.

After installing XCTU Utility, run it and go to add a radio module. Select the serial port at which Zigmo is connected and press finish. This will connect the Zigmo to XCTU.

Figure 5: Connecting Zigmo/Router to XCTU

After double clicking the added module, a list of parameters will be displayed on the right side. Select the load configuration file from the top and select configuration file form the location where you downloaded it earlier.

Now press the write button on top to write these parameters. Close the XCTU utility and open the LabVIEW utility and follow the steps in getting started section to communicate with sensor.

Figure 6: Loading a default profile to Zigmo/Router

Modes of Operation

This module incorporates 2 modes of operation, these are

  • Run Mode
  • Configuration Mode

Run mode is the standard mode, the module will always enter Run mode if no button is pressed during Power-up/Reset. Configuration mode is intended to configure sensor parameters and the X-bee parameters on the sensor end. Note that the Sensor end X-bee is only configurable via the sensor controller using the commands provided in device manual. Figure 7 illustrates these modes.

The device sends a startup packet which can be used to determine the mode in which it is operating. These packets are shown in Table 2.

Mode Selection Process

The CFG button on the module is used to change mode. If CFG button is pressed and the module reset button is pressed, the module will enter the configuration mode. The amount of time CFG button has to be pressed is shown in Figure 7.

Note that settings only take effect after the reset.

Figure 7: Mode Selection Process
Frame Communication at Power up

In figure 8,  Mode bytes highlighted in red can be compared with the values provided in Table 2 to determine the mode in which the sensor is operating. Node ID is the ID of the given sensor while sensor type determines the type of sensor. Both of these can be used to determine the exact sensor which is sending the information.

A shown in second column in Table 2, the sensor configures its PAN ID automatically depending upon the mode it is working in. During factory reset it sets the PAN ID to the value given in table therefore the factory reset frame will only be received if your Zigmo/Router PAN ID matches this ID. Please note that right after factory reset the sensor enters configuration mode therefore its PAN ID is changed again and a new frame is generated. All 3 type of frames are shown in Figure 9, Figure 10 and Figure 11.


The factory default settings are shown in Table 1. For parameter description please refer to the section on configuration.

Table 2: Mode Bytes for different sensor modes (* this frame is followed by configuration frame as shown Figure 7)
Figure 8: Typical Communication at Power Up, Transmitted packet (left) Received packet (right)
Figure 9: Run Mode Power up frame
Figure 10: Configuration Mode Power up frame
Figure 11: Factory Default Power up frame

Run Mode

Standard data transmission mode is the default mode of operation of this sensor. In this mode the sensor sends periodic packets to destination receiver. During the time it is not sending packets, it sleeps and conserves power. Sensor end X-bee operates in API mode and sends packets to the saved destination address on the network specified by the saved PAN ID. Figure 12 illustrates an API packet transmission and reception.

Packet reception at receiver end is ensured by the device by retrying up to 3 times if no acknowledgement is received that the packet has been successfully received. The device uses the acknowledgement functionality available in API mode in X-bee devices therefore user does not need to worry about sending acknowledgements for every packet.

Figure 12: Transmit packet detail (left), Received packet detail (right)

The detail for API packet received at PC end can be read from the X-bee manual available from Digi. The detail of Payload section of packet is shown in Table 3.

Typical response from the device in Standard data transmission mode is shown in Figure 13 and Figure 14. The utility shown in Figure 14 can be downloaded from the website.

Table 3: Packet payload field and its description

The detail for API packet received at PC end can be read from the X-bee manual available from Digi. The detail of Payload section of packet is shown in Table 3.

Typical response from the device in Run mode is shown in Figure 13 and Figure 14. The utility shown in Figure 14 can be downloaded from the website.

Frame FieldOffset (Payload Section)Fixed Value
(if any)
Header to differentiate various type of packets
Node ID10x00 Factory Default
Node ID to differentiate up to 256 nodes in a network. User configural values
Used to determine firmware version programmed in the device
Battery VoltageMSB 3

Sampled battery voltage of the device.

Battery Voltage=((Battery Voltage MSB x 256+Battery Voltage LSB) x 0.00322 V

Packet Counter5
It is an 8-bit counter that increments with each packet transmission. It can be used to detect missing packets.
Sensor TypeMSB 60x00
Two bytes to determine sensor type. It can be used in conjunction with Node ID to create sensor networks of up to 256 nodes for a single type of sensor and multiple such networks can coexist and can be differentiated in processing software on PC end
MSB 70x1B

Sensor Status as defined below

Decimal ValueStatus
-1Invalid Argument
-2Internal sensor communication failure
-3Invalid sensor discovery
-4Invalid length

Temperature data (16 bit signed Output)

          Temperature (°C) = ((Data[0]<<8)+Data[1])/100


Pressure Data (32 bit Unsigned Output)

Pressure (hPa) = ((Data[0]<<24)+(Data[1]<<16)+(Data[2]<<8)+Data[3])/100


Humidity Data (32 bit Unsigned Output)

Humidity (%RH) = ((Data[0]<<24)+(Data[1]<<16)+(Data[2]<<8)+Data[3])/1000

Gas Resistance19/Data[0]

Gas Resistance Data (32 bit Unsigned Output)

Gas Resistance (ohm) = ((Data[0]<<24)+(Data[1]<<16)+(Data[2]<<8)+Data[3])


IAQ Data(16 bit Unsigned) (Range: 0-100)

          IAQ = (Data[0]<<8)+Data[1]

Figure 13: Run mode packets being received in a terminal (Hex mode)
Figure 14: Run mode packets being received in our free to use LabVIEW utility (For custom made utility for your specific requirements please contact support)

Configuration Mode

Configuration mode is intended to setup the device over the wireless link. Entering configuration mode was already explained in the section “mode selection procedure”. User can also setup X-bee communication and networking parameters using this mode via PC. Note that settings only take effect after reset and are stored inside the device.

In configuration mode, the device sets its X-bee pan id to 7BCD (Hex). Also, the destination address used by the sensor is extracted from the incoming packet (source address). This ensures that once you put a device in configuration mode you just need to change the PAN ID of your Zigmo to match with sensor and start configuring your device. You can change the PAN ID of your Zigmo using XCTU from Digi. If you use our LabVIEW utility, it will automatically change Zigmo PAN ID once you open the configuration window. When you exit this window your PAN ID will be restored to old value.

A standard configuration packet and its fields are explained in Figure 15. Its possible responses are also shown. The commands supported by this sensor are shown in Table 5, these can be used in the Parameters field of Payload section. The sensor responds to these commands with an acknowledgement if the process completed successfully or with an error if it failed to setup a parameter. The respective Data and Reserve section length and values are shown in Table 6 for the case of acknowledgement. In the case of error, the reserved section will be fixed and not used, while the Error number byte will determine the type of error returned. These errors are mentioned in Table 7.

Figure 15 depicts standard communication between Zigmo/Router and sensor. Sensor commands have variable length frames whereas responses received from sensor are fixed length. The 2 scenarios are also shown, where a command can result in an acknowledgement reception or an error reception at the Zigmo end.

Examples for setting parameters in configuration mode are shown in Appendix A. Note that incorrectly setting some of the critical settings such as setting PANID and Destination address can disable further communication between a Zigmo and the sensor. Hence, these settings are saved in the sensor but they take affect after a reset so that the communication is not lost.

Figure 15: Configuration mode communication
Table 5: Configuration Commands and their respective headers, sub command and Parameter field
Table 6: Acknowledgment data for various commands and the size of reserve section in each case
Table 7: Error numbers and their description

The UI, shown in Figure 16, can be used to configure the wireless sensor. At startup, it automatically changes the Zigmo PANID so that it can communicate with a sensor in configuration mode (indicated by the Led on the top right). Upon exit, the PANID of the Zigmo is restored to old value.

Individual settings can be programmed using the single command column.
The AUTO PROGRAMMING check option allows the user to setup multiple sensors with the same settings. In such a scenario, the user will be required to enable each check box for enabling a setting, enter the value for each setting if required and then check the auto programming check box. Afterwards, when a sensor is powered up and enters configuration mode, the PGM MODE DETECTED Led will flash and automatically program the checked settings. User can also program multiple settings by clicking the APPLY SELECTED button. Moreover, settings can be read using the individual buttons or all settings can be read using the READ ALL button.


Figure 16: Configuration mode User Interface

Appendix A

Configuration Commands

1. Set Broadcast Transmission

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F7 0100 001B E1

2. Set ID and Delay

Command For COPY: 7E00 1710 0000 0000 0000 00FF FFFF FE00 00F7 0200 001B 0000 0005 DB

3. Set Destination Address

Command For COPY: 7E00 1710 0000 0000 0000 00FF FFFF FE00 00F7 0300 001B 1234 5678 CB

4. Set Power

Command For COPY: 7E00 1410 0000 0000 0000 00FF FFFF FE00 00F7 0400 001B 03DB

5. Set PANID

Command For COPY: 7E00 1510 0000 0000 0000 00FF FFFF FE00 00F7 0500 001B 7CDE 83

6. Set Retries

Command For COPY: 7E00 1410 0000 0000 0000 00FF FFFF FE00 00F7 0600 001B 04D8

7. Read Delay

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F7 1500 001B CD

8. Read Power

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F7 1600 001B CC

9. Read Retries

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F7 1700 001B CB

10. Read Destination Address

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F7 1800 001B CA

11. Read PANID

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F7 1900 001B C9

12. Enable Encryption

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F2 0100 001B E6

13. Disable Encryption

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F2 0200 001B E5

14. Set Encryption Key

Command For COPY: 7E00 2410 0000 0000 0000 00FF FFFF FE00 00F2 0300 001B 0011 2233 1122 3311 2233 1122 3311 2233 44A2

15. Set Gas Temperature

Command For COPY: 7E00 1510 0000 0000 0000 00FF FFFF FE00 00F4 0100 001B 015E 85

16. Set Gas Duration

Command For COPY: 7E00 1510 0000 0000 0000 00FF FFFF FE00 00F4 0200 001B 00C8 1B

17. Read Gas Temperature

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F4 0400 001B E1

18. Read Gas Duration

Command For COPY: 7E00 1310 0000 0000 0000 00FF FFFF FE00 00F4 0500 001B E0

Appendix B

Frame Checksum Calculation

In order to successfully communicate over the API protocol, checksum is of vital importance. The X-bee at either end will reject packets if the checksum is not matched. Checksum is also checked by the sensor controller and LabVIEW utility for added security.

For sending packets, checksum calculation works as follows

  1. Add all the bytes and keep the lower 8 bits of result (Excluding the frame delimiter and length)
  2. Subtract this value from 0xFF (hex)
  3. The resultant value is the checksum
  4. Append this byte at the end of the original packet for sending

Consider the example for the command Set Broadcast shown in Figure 19 in A APPENDIX and see that the calculated checksum matches with the checksum sent by the terminal/LabVIEW

Although checksum is matched by the X-bee itself, but for understanding follow these steps to match checksum at reception

  1. Add all the bytes including the received checksum (Exclude the frame delimiter and length)
  2. Keep only the last 8 bits
  3. If the result is 0xFF, the checksum is correct and the packet can be processed.

Consider the example of the command Set Broadcast shown in Figure 19 in A APPENDIX and see that the received packet checksum verifies since the result is 0xFF.