Wildfire Sensors require 14 days after deployment to be calibrated to the environment. During this time the they do not provide useful data.
Sensors are Calibration-ready upon delivery
When a sensor is delivered to the customer, it is charged up and calibrated and ready for deployment. No additional settings need to be made to the device.
When a Wildfire Sensor has been deployed and is charging, the status icon is Grey. When it is fully-charged, the status icon changes to Orange to indicate the Sensor is calibrating. When calibration is complete (14-days), the status icon becomes Green.
After the Wildfire Sensor has been mounted, it requires 1 day to fully charge the supercapacitors.
Once charged, the sensor’s solar panel continuously charges the supercapacitors during daytime.
Use of semiconductors
The Wildfire Sensor's power supply is stored in supercapacitors rather than rechargeable batteries as rechargeable batteries can potentially ignite. Using batteries would defeat the purpose of a wildfire detection system.
For more information, see Silvanet Wildfire Sensors.
After the Wildfire sensor has been fully charged, the sensor begins a 14-day initial calibration.
Once mounted, the Wildfire Sensor runs a calibration to prepare the device for fire detection. During this period, the Sensor does not provide any useful data may send false fire alerts, even after a month after deployment.
After this "settling in" period, the Wildfire Sensor is ready to detect fires.
Interactions after calibration period
After interactions with the Wildfire Sensor, it requires at least 5 days to return to steady state.
For more information, see Sensor normalization.
Install Wildfire Sensors using tree nails or garden wire, then let them calibrate for 14 days before they are ready to detect fires.
Practice safety first
Keep safety foremost when attaching sensors to trees. Make sure the ladder is stable when leaned against the tree, especially when leaned against thinner trees. Have the second person hold it to stabilize it while climbing the ladder.
Let the sensor calibrate after installation
After a sensor has been deployed and calibrated, do not interact with the sensor as this may cause errors with sensor values and could reset the sensor calibration.
AFTER SENSORS HAVE BEEN DEPLOYED, CALIBRATED AND SETTLED, DO NOT INTERACT WITH THE SENSORS IN ANY WAY.
Select a healthy tree
When locating a tree on which to install a sensor, look for indications that the tree may be in poor health. Also ensure the tree is not planned to be cut down or in any way unlikely to survive for the duration of the lifetime of a sensor. Find another tree within the designated radius (20m) of the planned location.
Average time to install a sensor
The average time to install sensors is about a half-hour per sensor. This includes finding the tree, setting up the ladder, scanning the QR Code, installing the sensor, then heading to the next deployment location.
Plan for a day's device deployment. Ensure you have brought sufficient sensors, treenails, spacers (and garden wire, if required) for the day's installation plans.
Ensure correct range
1 km to nearest Mesh Gateway: Ensure a Mesh Gateway is within range, which is no further than 1 km from the Wildfire Sensor.
Sensor density
WUI: 0.7/ha to 0.1/ha Based on WUI (Wildland Urban Interface), Dryad recommends 0.7/ha sensors for a dense WUI and 0.1/ha sensors for a sparse WUI. Spacing between sensors should be 80 m to 100 m for areas of high human activity, 400 m to 500 m for areas of low human activity.
Mount Wildfire Sensor correctly
Select a healthy, stable tree: The tree should be closest to the GPS coordinates set for a sensor using the Silvanet Deployment app. Also, ensure the tree is healthy and not likely to fall over or be harvested.
Above 3 m above forest floor: Install the sensor on the tree approximately 3 meters above the level of the forest floor. At this height, the device is most sensitive to fire detection and obtains an increased amount of light on its solar cell. Furthermore, at this height it avoids disturbances from most human and animal interactions.
Towards sun (at noon): The sensor needs to be oriented towards the direction of the sun (where it would be at 12:00 noon). Use a compass to identify true South (in the northern hemisphere) or true North (in the southern hemisphere). This maximizes the amount of light that hits the solar panel.
Use the spacer correctly: A 2 cm spacer is provided to deploy the sensor slightly away from the trunk of the tree. This avoids direct contact with the tree and allows tree sap to flow down the tree behind the sensor. The spacer also helps keep the sensor away from the moisture in the tree. Furthermore, the spacer allows the sensor to hang vertically rather than laying directly against the bark of the tree which could cause it to tilt at an angle. Also, hanging the sensor vertically improves the radio range of the device.
Before mounting the Wildfire Sensor, scan the Device ID using the Deployment app to register the Sensor and provide its GPS location with the Silvanet Cloud.
Device ID
Each Silvanet Wildfire Sensor has its own unique Device ID (also referred to as Serial ID). It is provided as a unique text string as well as a QR Code printed on a label attached to the Sensor.
Relocating a Wildfire Sensor
If a Wildfire Sensor has been relocated, update the latitude and longitude of the device in the section of the Site Management app.
In the Silvanet Deployment app, select a Site.
In the list of devices that appears, select a Wildfire Sensor. Alternately, select Show Devices on Map.
On the page that appears, tap Register Device. The blue dot on the map show your current location.
Finding the deployment location
Note in the figure above the Sensor is 120 m away from the user. Use this map to move towards the deployment location.
If you tapped Show Devices on Map, the map shows an overview of the Site on the map. Your location is indicated by a blue dot.
Once the deployment location is found, register the Device ID.
Gen 2 devices: Scan the device's QR Code which is attached to the back of the Wildfire Sensor.
Gen 3 devices: Tap the Smartphone against the NFC logo on the front of the device to automatically register the Wildfire.
The Deployment app automatically fills in the Sensor's latitude and longitude using the Smartphone's GPS location.
Entering Device ID (Serial ID) manually
If the QR Code cannot be scanned, the information can be entered manually. Tap Enter Serial ID Manually to continue.
Calibration period
After the Registration successful message appears in the Deployment app. Brief instructions are provided for mounting correctly the Wildfire Sensor.
Tap Confirm.
Dismiss the dialog by tapping Close or you can view the Device Details by tapping Show Device Details.
See also
After successfully scanning the QR Code, the Deployment app shows a Registration successful screen. The device icon changes from Planned to Deployed. For more information, see .
After the Wildfire Sensor has been mounted, it enters a 14-day calibration period. The device icon changes to Calibrating (orange). For more information, see .
After you have correctly mounted the Wildfire Sensor (see ) and is fully charged, an Installation successful message appears.
For details, see .
Install Wildfire Sensors using treenails or garden wire, then let them calibrate for 14 days before they are ready to detect fires.
Wildfire Sensors can be mounted on a tree using treenails (long term) or garden wire (temporary).
Treenails are wooden pegs used to securely mount sensors to a tree. As they are made from wood, they do not affect the health of the tree. Over time the tree's moisture causes the treenails to expand which securely attaches the sensor to the tree.
Drill a 10 mm hole into the tree 3 m from the forest floor on the side of the tree where sunlight would strike the tree at 12:00 noon. The treenails are fed through a loop in the sensor and a spacer and then hammered into the tree.
With the help of an assistant, stabilize the ladder against the tree.
Locate the correct height (3 m) and direction (facing sun at 12:00 noon).
Carefully remove a small portion of the bark with an axe at that location. Try not to excessively damage the tree.
Carefully drill a hole approximately 6-7 cm into the tree using the 10mm drill bit. Do not drill deeper than this recommended depth to prevent unnecessary damage to the tree. When drilling into a hardwood tree, start with a smaller drill bit to drill a pilot hole then drill with the 10mm drill bit to complete the drill hole. Ensure you are using a drill bit for wood.
Insert a treenail through the sensor's loop, slip a spacer onto the treenail and then carefully hammer the treenail into the hole. Ensure the treenail is not damaged by the hammering.
Ensure the sensor is securely deployed to the tree and hanging loosely and vertically.
Sensors can be mounted using garden wire for short term installations. Garden wire is typically used in agricultural and garden settings such as greenhouses. This solution should only be used for a limited time as the wire will eventually interfere with growth in the tree's girth.
With the help of an assistant, stabilize the ladder against the tree.
Locate the correct height (3 m) and direction (facing sun at 12:00 noon).
Cut a length of garden wire twice as long than the circumference of the tree.
Insert garden wire through the spacer and sensor as shown below.
Tighten the garden wire around the tree. Ensure it is securely attached and that the sensor cannot slip or move.
Allow the Wildfire Sensor to calibrate for 14 days.
See also
For details, see Sensor Calibration.
Wildfire Sensors require time to stabilize depending on the type of activity it has encountered.
Data during stabilization periods
While the Wildfire Sensor is stabilizing, it does not provide any accurate or usable values.
After a Wildfire Sensor runs internal gas scans to test air quality, the sensor needs approximately 30 to 60 minutes to be ready to detect fires (stabilize).
When the Wildfire Sensor's internal Bosch gas sensor detects , it performs a set of gas scans to determine the type of VOC. After these gas scans are complete, it begins to stabilize and return to normal values.
This stabilization period allows for the dissipation of any smoke retained inside the sensor mesh (a small pot with a mesh cover used by the gas sensor). Ideally, the longer the wait, the more time the smoke has to dissipate.
Interactions cause the Wildfire Sensor to repeat of the calibration process, but not a complete 14-day recalibration. This type of recalibration takes at least 5 days.
This includes, but not exclusively, the following types of interactions:
Touching the sensors, such as adjusting the angle of the sensor or attempting to pull it off the tree
Moving the sensors to another tree or to another location on the tree
Animals or humans breathing directly on the Wildfire Sensors.
Exhaust from vehicles (especially diesel trucks).
Bringing any source of VOC near the sensor such as cigarettes or fumes from running machinery.
Mounting the Wildfire Sensor at 3 meters height
Attaching the Wildfire Sensor to the tree or pole at least 3 m above the forest floor can prevent intentional or inadvertent interactions. If it is moved to a new location, it automatically runs the calibration process again (for 5 days).
