Would there be a shunt that would integrate into the PI OS ? Not sure what a hall effect sensor is (learning needed, google)
I will try and figure it all out and maybe when I have more £$£$ look at doing the swap out on controllers as you have suggested
Many thanks
Robert
The shunt is the physical device. then you need the device to read the data - that is the monitor (so the BMV in the case of Victron).
The Venus System is essentially a method to collate the data from the various devices.
Here are a couple of screenshots of the Venus system on the Van install I did recently to illustrate:
This is the System, running on a Pi with the Solar Controller installed and no BMV Monitor fitted
Head Unit with Remote Console by
David, on Flickr
The only info the Pi has on the battery is the voltage, as provided by the Solar Controller
(the reason the PV is showing negative is that I had a device connected to the LOAD output on the MPPT and no solar panels fitted)
And a later photo after the BMV was added
Head Unit running Venus Remote Console by
David, on Flickr
Now the BMV is connected, the Battery SOC is shown, the power used by the DC system is known and the charger going into the Battery is known. (The Pi knows how much the solar is putting in (37W) from the MPPT; It knows from the BMV how much power is going into or out of the battery (19W) and so can calculate from the difference how much is being used by 12V Devices (18W)
To know the AC input and output requires Devices that can be connected to the Pi as well - so an Inverter with VE.Direct for example, or a Multiplus Charger/Inverter with its VE.Bus connection. Victron have just brought out a Mains Charger that can be connected to the Venus OS but it is a silly price for what it does.