Simple DIY ethernet battery monitor design?

[off.the.grid]

Is there anything readily and cheaply available that can connect to my router and essentially read out the battery voltage on an HTML page?
I have a few remote sites running APs, cameras etc and would like a way to monitor the battery voltage remotely.
Perhaps an added feature could be to trigger a relay if the battery voltage goes below a pre set level.
Can probably be easily done with an arduino if there is some project already out there.

 

[shvm]

Can probably be easily done with an arduino if there is some project already out there.

Sounds like a job for Arduino, ESP32, RPi Pico

But my recommendation would be going with ESP32 because they're far more versatile, capable, faster while being cheaper and easier to program.

 

[再生可能 エネルギー]

There is the Smart Battery Sense from Victron, that can be access using a Victron WiFi App.

I wonder if this device could also be accessed using the Victron Energy's Remote Monitoring Solution (VRM) ?

 

[off.the.grid]

Sounds like a job for Arduino, ESP32, RPi Pico

But my recommendation would be going with ESP32 because they're far more versatile, capable, faster while being cheaper and easier to program.

Was thinking about an ESP32, those have wifi built in which is great if I was using wifi.
I think there is an ethernet module available though?
I have a few sites I'm planning on rolling this out on. The idea is I can manage the sites from a single web page.

 

[shvm]

Each ESP will have their own IP addr. and thus will act as its own information server.

The idea is I can manage the sites from a single web page

You need to something to aggregate the information coming from multiple ESPs and present them on a single web dashboard for you. Something more knowledgeable than me can chime in this regard.

 

[LEumel]

If you have a bms installed, you could even (depending on the bms) use the CAN or RS485 connection to read more data. What BMS do you have?
In Venus OS (the Victron OS for RaspberryPi, which can talk to a lot of devices via the Pylontech protocol) there is a "large" version which includes NodeRed, a custom Dashboard web interface. There's quite a few videos about NodeRed on Venus OS, you might want to look into those.
You can get a RasPi with ethernet port if you don't want to be dependent on a vulnerable or unstable WiFi connection.
Good luck with your build!

 

[off.the.grid]

Each ESP will have their own IP addr. and thus will act as its own information server.


You need to something to aggregate the information coming from multiple ESPs and present them on a single web dashboard for you. Something more knowledgeable than me can chime in this regard.

The idea was I have a basic HTML page that just reports the voltage, but might be other ways to transmit the data out to a webserver, so will talk to my web developer to see what he suggests.

If you have a bms installed, you could even (depending on the bms) use the CAN or RS485 connection to read more data. What BMS do you have?
In Venus OS (the Victron OS for RaspberryPi, which can talk to a lot of devices via the Pylontech protocol) there is a "large" version which includes NodeRed, a custom Dashboard web interface. There's quite a few videos about NodeRed on Venus OS, you might want to look into those.
You can get a RasPi with ethernet port if you don't want to be dependent on a vulnerable or unstable WiFi connection.
Good luck with your build!

The battery packs are ones I bought preassembled with their own BMS board installed. They are 29V, 7S3P banks comprised of 5AH 21700 cells.
There is no way to communicate with this BMS, its basically there to protect the batteries and balance them, not to report voltages, charge/discharge, etc.
Im charging them using a Witek MPPT PoE switch, im hoping they will have a newer model available soon that will have management features added, but for now I will need to use something extra added.
I would simply forward the ports out and point it to the IP address of the ESP32, them i could plot it onto a graph or something i guess.