There are two different sensor types:
- Periodic sensors - send the state (update) to the platform every 15 minutes.
Examples: Weather sensors, time sensors, power status sensors (e.g. most of smart lamps and sockets), temperature sensors and many other numeric sensors
- Streaming sensors send their status immediately after change is registered.
Examples: Security sensors like door/window sensors, motion detectors, water detectors, smoke detectors
- The storage duration of the sensor status is preset to 1 second for these sensors, so that connected actuators can only be triggered immediately after the transmission of the sensor status (for one second).
An overview of different sensors and basic information about creating a project can be obtained by clicking on the following link: How to create a project with a Project Editor?
Sensors have 2 different options available in the advanced settings menu.
First option allows to set a state persistence for the sensor in seconds. That means, that a changed state will be saved for that amount of time. So, the following elements will be triggered only during that time window. The default state for the streaming sensors is 1 second
Second option is a permanent state. That means that a sensor state will be saved until it's overwritten by another state. That's the default state for the periodic sensors
Let's say you would you like to know
- whether one of your windows is still open when you leave the house?
If any window is opened (or gate) and motion is detected, then lamp will shine. Without permanent state it would be impossible to make it work, as an opened state for window sensor will not be saved. If state persistence is not permanent, then sensor will lose state after several second (1 by default). However, motion sensor should not have permanent state in this case., as soon as motion is detected, it will trigger the project and check the window states via logic gates.
- After saving the project you have to trigger each sensor once to save its status in the project. Then the sensor always has a status in this project. In this example it would be the opening or closing the windows that are used in the project.
- For Periodic Sensors the status or numerical value usually gets updated within 15 minutes after saving the project, so the project may not work properly until the sensor gets new data.
Example: If the light should only be turned on automatically at night (periodic day or night sensor) when there is movement in the corridor, the project becomes active about 15 minutes after the project is saved and can then turn on the light at night when there is movement.
Once sensor is linked to an actuator, you can select the actuator and check the the advanced option in the end of the settings side window
There you can find two options:
- Trigger on State
- Trigger on State change
Trigger on state will make actuator trigger anytime it gets the selected sensor state.
Trigger on state change has two extra fields: From and To. There you can define different cases when the actuator should trigger. For both From and To states you can select any available sensor state (e.g. True / False or Below / In Range / Above) as well as an option All except current state
The last option All except current state will make actuator trigger an every sensor state change.
That can help to define more specific projects, where actuator should trigger only on specific case
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