Using a PLduino as a backup for Rpi3 Solar power Controller

This is a controller from called a PLduino that’s Mega 2560 based and comes packaged and ready to code and mount on a din rail.

Credits go to @adam and @kreggly for their awesome assistance in coding IDE and python. I needed to have a backup micro to the Rpi3 in case it died or lost communication. Both micros monitor and control a solar power system in my home overseas. This project is a continuation of a previous project and is still a work in progress.

Digital inputs to monitor state, 6 relays to control fans and reset inverter and Rpi3

The PLduino had 6 built in relays, 8 analog inputs, 8 digital inputs and 8 open collector digital outputs. Other GPIO can be accessed on the board itself, scl and sda are available at the RTC which I will add i2c temperature sensors,

Triggers for now are set to notify if Rpi3 is offline/online, I setup a relay on GPIO 16 and set it to invert, on reboot it will go high every time(nature of the beast) and input to the PLduino. Notification if the inverter is in alarm and needs resetting. Notification if inverter goes offline/online.

(Did you use the Scheduling feature?) NO

Dashboard sharing if you want to view project

More to follow later.



Awesome! Can you add some pictures? :slight_smile:

Coming soon!

Photos yay!


Here’s the Sketch.
I expanded what @kreggly showed me.

Latest Project Tab. Ran across a thread that made me realize I didn’t know multiple device widgets could be dragged to 1 project, now that a DOH! moment. Some widgets are redundant because one is backing up the other.

I used the trigger function for the “Reset Solar Rpi3a” button to make it momentary. Only needed a quick pulse to start the python reboot script.Same goes for the “Reset PLCdiuno” button.

Will publish the reboot script shortly that @adam wrote for me.

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@kreggly, I finally installed the 1 meg rpacks and changed the float values to 55. When the power supply reaches 10v then the reading shows 54.95v. Tried other values but same difference. Even tried playing with the formula but to no avail. Just can’t break past the 10v barrier no matter the figures I use.




What R packs did you replace?

If you want the voltage divider to work properly, you should leave RN2 at 100K and change RN1 to 1Meg.

Otherwise you have the same ratio you had before and will see the same result.



Ahah! As he smacks his forehead repeatedly.

Thanks Craig!

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