[FEATURE]:Allow using the same actuator in multiple areas with priority-based control

[GamingLPyt]

Problem:
Currently, a single actuator (e.g., a heating relay) can only be assigned to one area. In more complex setups with multiple critical sensors (for example a normal heating sensor plus an independent safety/overheat sensor), it becomes necessary to control the same actuator across multiple areas.
At the moment, this is not possible without duplicating hardware or using workarounds.

Requested Behavior:
Allow a single actuator to be assigned to multiple areas.

Each area can be given a priority level (1 = highest).

If an area with a higher priority triggers an action (e.g., overheat condition), it overrides all lower-priority areas and forces the actuator to the required state (e.g., heating OFF).

The actuator returns to normal operation based on the next valid lower-priority area once the higher-priority condition is no longer active.

Example:
Area Safety → Sensor A → Priority 1

Area Heating → Sensor B → Priority 2

If Sensor A detects an over-temperature condition → heating relay turns OFF, no matter what the heating area demands.

When the safety condition clears, normal heating logic resumes.

Why this is useful:
No need for duplicate actuators or hardware hacks.

Makes advanced safety logic possible.

More realistic and scalable for users with complex terrarium, rack, or multi-sensor environments.

Keeps configuration cleaner and more intuitive.

[theyosh]

Hi,

I have thought about this, but I disagree.

Because what you describe is already possible/the default.

You can select multiple sensors for 1 area. When one is failing the rest will take over. So redundant sensor logic is possible. And TerrariumPI will always try to keep the sensor values between the alarm values. As soon that is goes below or above, the relay will act. When that is failing, a second relay setup will also fail, because the relay hardware is failing. So there is nothing that can be done within TerrariumPI.

Using priority system will not change this. The relay is failing, and will keep failing without human intervention.

No need for duplicate actuators or hardware hacks.

Creating duplicate relays is not that difficult https://theyosh.github.io/TerrariumPI/faq/how-to-use-a-relay-multiple-times/ (I see the documentation is broken)

Makes advanced safety logic possible.

The idea of TerrariumPI was not to include this advanced logic. This will require more documentation, and less people using this kind of stuff. Also there are more changes on wrong setups and other mistakes.

More realistic and scalable for users with complex terrarium, rack, or multi-sensor environments.

For this kind of persons there is an API to add extra complex logic outside TP. And your heat safety example is just the exact reason why there is an API.

Keeps configuration cleaner and more intuitive.

Disagree. This will add a lot more configuration settings in the GUI, which will make the area settings form even more complex and more fields.

So I am at the opinion that what you are looking for is something that I will not implement. As I read it, you are looking for an extra safety system. And that should never be created in the same software that is failing....

So I can only suggest to create your own script that do the testing based on the API provided data. And react when needed, also through the API.

[GamingLPyt]

Hi,

I’ve created my own script for the additional safety and control logic and I’ll upload it here in the issue.
Since the API is a bit too slow for my use case, I will eventually switch back to using your duplicate relay system, as it works more reliably for my setup.

I also think many users might run into similar situations as I did.
For example, I have six temperature sensors installed so I can track the air curve more accurately and adjust my fans and heating accordingly. I also wanted the lights to turn off at night when the door opens, and at the same time temporarily set the daylight lamp to 100%.

Right now, I’m hitting some limitations:
In the “add new area” section, I can’t pass different values — it always takes the maximum value that is defined. During the day, the light should only go up to 50%, but when I’m working on the terrarium it should be able to go up to 100%.
The fans also need more flexible control, because I don’t always need full power. Sometimes 50% or 80% is enough, since they get too loud otherwise.

Of course, I still need to refine my script. At the moment, the fans only turn on in an emergency and then jump straight to 80% or 100%. What I actually want is for them to react to different conditions so that the airflow stays balanced according to the temperature.

weather.py
utils.py
main.py
lights.py
heater.py
fans.py
sensors.py

config.json