Arduino home power monitor
At some point last year we had a "Smart" meter installed. The main advantage of this is that I no longer have to walk to ASDA to top up some card - I can do it online instead. I think there are many disadvantages to them though, too, although I don't go into them in this entry. One thing I was excited about was the possibility of being able to easily sniff the ZigBee network to monitor our gas and electricity consumption. Annoyingly I don't seem to be able to, probably due to some kind of encryption?
Giving up on that idea I thought I would just monitor the IR LED on the meter, so I went to eBay and ordered a few BPW34F photodiodes. Later I check the meter and it turns out it doesn't have an IR LED for flashing power consumption as impressions - the old one did. This one has some complicated IR tx/rx thing which I don't even want to attempt to figure out. It does have a RED LED though, which flashes 3200 times per kWh.
So, I went and grabbed an Arduino Uno and LDR sensor from the loft. No need for any pull up/down resistors, the Arduino has software configurable pull up/down. No need for any transistors or op amps. All of this can be done in software.
Here is the final result:
I decided to finally put one of the small 128x64 SPI OLED displays to use. The end result is fairly stylish. Surprisingly, this ended up being very accurate. Our "smart meter" console thing is usually only 1 watt or so off the value displayed by the Arduino.
The only problem is that this isn't really much better than just looking at the "normal" console. So. I went and grabbed an ESP8266, but unfortunately the story ends here for now. My usual method of programming appears to have failed me, possibly a problem with the programmer. New one on order, will have to update soon. I want to log this data!