My BMS system
The BMS system finally started working.
The missing part was the so called concentrator, which interfaces several RS485 bus lines to the server through a single RS232 or USB.
The interior of the concentrator.
This is just a prototype, a proof of concept, that the SPI backbone can work. The final design will be more compact.
Close up of the line cards.
The whole stuff mounted in the rack.
After more then one year of operation of the concentrator, I started to design the controller board, which integrates basically the concentrator, and a computer. The chosen SBC is the Onion's omega plus board. This runs a OpenWRT and perfect for the purpose.
The board is more or less ready to manufactured. I use KiCad to design the board. With the new v5.0.0 release, one can easily export and display 3D data with multiple boards. Mine integrates two power supply boards which is orthogonal to the main board. Also, there'll be an add-on daughter board to the main board.
On the front you can see the interface cards, on the top left, you can see the power supply modules. The gray flat object on the top right is the Omega2.
The temperature sensor
The temperature sensor has three inputs. This is sufficient to mount on a heat exchanger, so it can monitor the input and output temperature, and ambient temperature.
The front of the temperature sensor
The back of the temperature sensor
The relay module
To be added.