I needed to power a pump at a remote pond for a few minutes an hour and was surprised to find that the load switch on Renogy charge controllers didn't have any auto modes that could be used in the day. Here's a screenshot from the manual showing the available modes of the load switch:
I needed to turn on the load switch whenever there was sufficient power from the solar panel. The next surprise was that there wasn't any Arduino or ESP32 project to read the data from the Renogy charge controller's RS232 port. There's a couple of projects for Raspberry Pi or similar, but that's overkill for my project, and in my experience a Pi is a lot less likely to be running in a year than an ESP32 in a solar environment. I'd rather not have to worry about properly shutting down a Pi, keeping its OS up to date, etc. And apparently there's some kind of global Raspberry Pi shortage at the moment.
Anyway I posted my code to Github in case anyone else finds it useful:
So far I've only tested it on the Renogy Wanderer 10A and 30A, but it *should* work on any Renogy charge controller. And it's easy enough to add other charge controller brands that have RS232 or RS485 ports. If you test with a Renogy controller and it doesn't work or misses some registers, please let me know.
A couple of pics of my installation:
This is the pond:
And we need to maintain siphon on the pipe going to this cattle trough.
At the moment we're just using a small cheapie boat bilge pump, but since it's only on for about 8 minutes a day (a minute every hour while the sun is out) it *should* last a long time.
I needed to turn on the load switch whenever there was sufficient power from the solar panel. The next surprise was that there wasn't any Arduino or ESP32 project to read the data from the Renogy charge controller's RS232 port. There's a couple of projects for Raspberry Pi or similar, but that's overkill for my project, and in my experience a Pi is a lot less likely to be running in a year than an ESP32 in a solar environment. I'd rather not have to worry about properly shutting down a Pi, keeping its OS up to date, etc. And apparently there's some kind of global Raspberry Pi shortage at the moment.
Anyway I posted my code to Github in case anyone else finds it useful:
GitHub - wrybread/ESP32ArduinoRenogy: Reads data from a Renogy solar charge controller's RS232 port with an ESP32 or Arduino
Reads data from a Renogy solar charge controller's RS232 port with an ESP32 or Arduino - wrybread/ESP32ArduinoRenogy
github.com
So far I've only tested it on the Renogy Wanderer 10A and 30A, but it *should* work on any Renogy charge controller. And it's easy enough to add other charge controller brands that have RS232 or RS485 ports. If you test with a Renogy controller and it doesn't work or misses some registers, please let me know.
A couple of pics of my installation:
This is the pond:
And we need to maintain siphon on the pipe going to this cattle trough.
At the moment we're just using a small cheapie boat bilge pump, but since it's only on for about 8 minutes a day (a minute every hour while the sun is out) it *should* last a long time.