The new code is progressing nicely. First step was to get a test table, updating in real time:
It was a big relief to figure out how to produce graphs again – e.g. power consumption:
The measurement resolution from the 2000 pulse/kWh counters is excellent. Here is an excerpt of power consumption vs solar production on a cloudy and wet winter morning:
There is a fascinating little pattern in there, which I suspect comes from the central heating – perhaps from the boiler and pump, switching on and off in a peculiar 9-minute cycle?
Here are a bunch of temperature sensors (plus the central heating set-point, in brown):
There is no data storage yet (I just left the browser running on the laptop collecting data overnight), nor proper scaling, nor any form of configurability – everything was hard-coded, just to check that the basics work. It’s a far cry from being able to define and configure such graphs in the browser, but hey – one baby step at a time…
Although the D3 and NVD3 SVG-based graphing packages look stunning, they are a bit overkill for simple graphing and consist of more code for the browser to load and run. Maybe some other time – for now I’m using the Flot package for these graphs, again.
Will share the code as soon as I can make up my mind about the basic app structure!