Sensor regions

The sensor regions solution watches temperature and humidity sensors spread over the regions of a site, for example the greenhouse, orchard and cold store of a farm. Each sensor has its own limits; each region has a floor plan with its sensors on it, coloured by their alarm state. One weather station completes the picture.

The model

Part	In the full installation
Site	Farm (asset kind Site)
Regions	Greenhouse, Orchard and Storage hall (kind Region) under the farm. Each region has the attribute floorPlan with the address of its plan image.
Devices	Five sensors per region, placed in their region, and one weather station placed in the orchard

The weather station is recognised on the board by its label, Weather station: its rows and markers open the Weather page instead of the Sensor page. Give your own station that label.

Profile: Sensor regions · Sensor

Key	Label	Unit
air_temp	Temperature	°C
air_hum	Humidity	%
battery	Battery	%
plan_x, plan_y	Plan position x, y	px
lat, lng	Latitude, Longitude

Profile: Sensor regions · Weather station

Key	Label	Unit
air_temp	Temperature	°C
air_hum	Humidity	%
acc_rainfall	Rainfall	mm
pressure	Pressure	hPa
light	Light	lx
wind_dir	Wind direction	°
wind_speed	Wind speed	m/s
lat, lng	Latitude, Longitude

The limit attributes

Every sensor and the weather station have six limits as server attributes:

Attribute	Default	Meaning
maxTempThreshold	32	Critical above
minTempThreshold	4	Critical below
warnTempThreshold	27	Warning above, up to the maximum
maxHumThreshold	88	Critical above
minHumThreshold	30	Critical below
warnHumThreshold	78	Warning above, up to the maximum

In the full installation each region’s sensors get their own warning temperature (24 °C in the greenhouse, 26 °C in the orchard) and the storage hall’s sensors are set as a cold room (maximum 8 °C, minimum 0 °C, humidity 40 to 95 %).

A device without one of these attributes is not checked by the rule that reads it. Change limits on the device’s Attributes tab, or write them from another system with the attributes API (POST …/attributes/server); see Telemetry and attributes API.

Alarm rules

Both profiles have the threshold rules; the sensor also has the battery rule.

Type	Severity	Condition	Debounce	Hysteresis
high_temperature	Critical	air_temp > maxTempThreshold	2 readings to raise, 2 to clear	0.5
low_temperature	Critical	air_temp < minTempThreshold	2 / 2	0.5
high_humidity	Critical	air_hum > maxHumThreshold	2 / 2	2
low_humidity	Critical	air_hum < minHumThreshold	2 / 2	2
temperature_warning	Warning	air_temp > warnTempThreshold and ≤ maxTempThreshold	2 / 2
humidity_warning	Warning	air_hum > warnHumThreshold and ≤ maxHumThreshold	2 / 2
battery_low (sensor)	Warning	battery < 20 %	1 / 1	2
device_offline	Warning	No message for 1,800 seconds (30 minutes)

Each rule opens and clears on its own. A sensor above its maximum has a Critical high_temperature alarm; the warning band ends at the maximum, so the temperature_warning alarm clears after two readings above the maximum, while the critical one stays open. For the design of such bands see Alarm rule cookbook.

The board

The board Sensor regions opens on the last day.

Page	Cards
Regions (main)	Regions table: the regions A to Z with their sensor count, ten a page; a row opens the region. Sensors on the map: every sensor and the station, named by label and coloured by alarm state. Alarm count: the open alarms of the board’s devices, with an All alarms button. Weather station: its latest readings. Active alarms
Alarms	Alarms of the sensors: the open alarms of every device, newest first, ten a page, search, export; a row or its Open button opens the alarm’s page
Region (hidden)	Region record (name, code, sensor count, use); Sensors of the region with online dot, temperature, humidity and battery; Floor plan; Alarms of this region
Sensor (hidden)	Temperature and Humidity with their lines; Alarm state; Battery (red below 25 %, amber below 50 %); Temperature and humidity on two axes; Alarms of this sensor; Readings
Weather (hidden)	The station’s readings with their lines, Wind on the compass, Temperature, humidity and rain, Alarms of the station, its readings

Colours on the maps and the floor plan

Colour	Meaning
Red	The device has an open Critical or Major alarm
Amber	It has another open alarm
Grey	It is offline
Green	No open alarm

The Alarm state tile of a sensor shows the worst of its open alarms: Alarm, Warning, Notice or Normal.

These colours come from compute scripts on the board. A board made from the template, or an organisation without alarms, colours the map by temperature instead: Cold below 4 °C, Normal 4 to 27 °C, Hot above 27 °C.

The floor plan

The Floor plan card of a region page draws the region’s plan image and places each sensor on it.

What	Where it comes from
The image	The region asset’s attribute floorPlan: an internal path or an https address of the image. Without it, a sample plan is shown.
A sensor’s position	The latest values of the sensor’s telemetry keys plan_x and plan_y, in pixels from the top-left corner of a 1,200 × 800 plan

Most real sensors do not send plan_x and plan_y. To place them:

1. Prepare the plan image at 1,200 × 800 pixels (or scale your coordinates to that size) and set its address as the region’s floorPlan attribute on Sites & Assets.
2. Give each sensor its position as two server attributes, for example planX and planY.
3. In the sensor profile’s root flow, before Save telemetry, add a Device details block that reads those two attributes and writes them into the message as plan_x and plan_y (target under msg.payload). See IoT data blocks.

Each stored message then carries the position too, which adds two data points per message. Markers cannot be dragged on the plan.

Notifications

The flow Sensor regions: alarm notifications tells the Admin role when an alarm of a sensor or the weather station opens or clears. It is stored switched off: turn it on in Automation. The role is reached in the app, by push where set up and in linked chat apps, not by e-mail or SMS; add address or phone rows for those. See Flow templates.

Known limits

Need	Status
An alarm count per region in the regions table	Not available: open a region to see its alarms, or read the map
A form on the board to edit a sensor’s limits	Not available: use the Attributes tab or the API
Default limits for a sensor that has none	Not available: a sensor without a limit is not checked for it. Set the attributes when you add sensors.
Hiding spare sensors on the board	Every device placed in a region is shown. Move spare sensors out of the region.

Related

• Install a solution
• Map cards
• Alarm conditions reference