question

Been there...

There are innumerable ways to do this sort of stuff and yes, logic gates are a valid approach but combining several messages into a single one that contains all the required data for those gate to work is tedious and not at all intuitive, as you will have discovered.

I use and recommend the following strategy...

Collect your tank data as and when it arrives, store those values in Flow or Global context using a change node to set the variables when data arrives.

I would also recommend initializing those variables at startup, setting a default value once. Persistent context storage is a good plan too but I don't know if that is available when running on a Cerbo.

Now the data is available to any node within context...
You can use a function node to perform all your logic in one node or, for a clearer picture of what is going on and to avoid actual code, you can use switch nodes to do the work.

Set a trigger node to fire periodically. Route its message through switch nodes that use the context data to determine which output the message will be routed to.

In your case, 2 switch nodes with the top output active when either tank is full and two copies to switch nodes with the top output active when a tank is empty. in all cases the second output is set to otherwise and acts as a default. (No tank/s so just used my first CV, SOC_24 as a placeholder...)

Now just hook then up...

Simple and clear... You could even use context vars for your setpoints...

Give me a shout if you need help...

Thank you for the reply Alistair!

For some reason the True of False that's being send every 5 second only seem to travel on the output of the switch configured at "otherwise", accept with the water left en right sensor.

The switch for the water sender should the false on the "otherwise" output, but simply doesn't.

As i have no clue how to store information in Node-red so this was my approach.

Every switch is the same for black and grey it's ">=90" for output 1 and "otherwise" for output 2

For Water it is "<=12"for output 1 and "otherwise" for output 2

In my thought running all the number 1 outputs parallel the relay should switch on when on of the tanks reached the value setting. And running all of the "otherwise" outputs in series should turn off the relay when all values are within limits.

As you can see the tank sensor are within limits but the relay is still set.

Also the relay only answers to "0" to turn off and "1" to turn on, that's why I added the last switch that translate "false" to 0 and "true" to 1.

At this moment I have variable resistor on the black and grey input, but the water tank inputs are fixed resistor, that's why the minimum is 12% for the water tanks right now.

Is it a possibility for you to upload the .json file, I think that would help a lot.

Thank you for your input this far, it nice to have someone else's input in this!

OK... That a node red thing... Each node only acts on what it gets in a message when it gets it, there is no remembering the last massage and using that info to, in this case, route the next one.

Since you need to inspect multiple conditions to make a decision any messahe yoiu want to process has to contain all the information needed to make that decision.

There several approaches to do this, including switch nodes that you send a message to set and they stay in that state until you tell them otherwise... See this. It is easy to use and intuitive, just like a switch, set it with a message, that isn't passed to its output, and it will pass or block anything else.

Storing data to use later is easy just use a change node and write payload to a global context variable...

Now you can do this

It is way less mucking about and if you always collect data and store it you can then use it in any combination anywhere... This my data gatherer for my 24 system, cant remember why I wasn't storing bus state but I only use it for a label anyway.

The change nodes on the left store the Global context vars, the Changed nodes prevent unwanted processing by only passing changed info to the dashboard.

I will send you some code shortly... But its worth sticking with it to get your head around how Node Red works.

To give you code I need to know which tank sensor is which... Ideally

This flow is working...
Disconnect your tank sensors so the the injection points will work for testing.

flows.json.txt Rename this to flows.json then import as a new flow.

Give me a shout if you have any problems with it.

Enhancements...

Use the sensor fault outputs to do something, stop pump, tell you about the issue, whatever.

Add an initial inject, just the once when the system boots, to set all the global's to within range. If you adjust the test 50 inject so it fires once at startup you will have done this.

Hi Alistair,

After a bit of testing it seems to be working perfect! Thank you so much!

I have restarted the Cerbo multiple times in multiple ways and it seems that all keeps working right away.

I removed the top limit on the water tanks, cause the pump is still aloud to run when the water tanks are full.

The Cerbo is set to a risistive input of 0-300 ohms, 0 ohm being 0% and 300 should be 100% full. If the resistive range is out of the limit of the Cerbo it won't give any signal, on the screen it simply says "Disconnected"

This has been a nice way to start learning about this, sometimes I'm amazed at the amount of way you can solve a problem.

Thank you Alistair!