Maxim DS onewire temp sensor home automation

Trying to create a hybrid Raspberry pi homebaked cheapie.

1. hookup to the solar heating water system (see prior blog article)
2. Add a power consumption sensor to monitor electricity use.
3. Add water temp and room temp sensors using 1wire dallas sensors

Starting from the bottom.

• The temp sensor https://datasheets.maximintegrated.com/en/ds/DS18B20.pdf is a bit harder to use on one wire with all sensors dropping off of it, but should work if I use the design guide here and keep to 40 meters and use good cable. http://pdfserv.maximintegrated.com/en/an/AN148.pdf . Will probably end up hooking into a Arduino instead of directly into a raspberry pi to get better timings, and then push the datas over serial to the pi directly. For sample codes https://create.arduino.cc/projecthub/TheGadgetBoy/ds18b20-digital-temperature-sensor-and-arduino-9cc806

A cheaper display here https://www.ebay.co.uk/p/Digital-Aquarium-Reptile-Thermometer-With-Probe-Freeze-UK-SELLER/1688591981?iid=111418097114

• Next up is the power. I have a standalone wireless monitor, which is technically on loan, want to try share this unit along, and get myself a pickup coil and wireless that is easier to hack. (wired or wireless does not matter really.) My intention is to buy a Maplin unit which they sell for £40, and then hack either the wireless (433 MHz) or the internet API it has https://www.maplin.co.uk/p/efergy-engage-hub-kit-n67nw .

More info on the Efergy , harvested from the navitron.co.uk forums is this kind blog link http://blog.krisdaniels.be/efergy-engage-api/ detailing some of the protocols.

• Lastly hookup into the solar panel data feed, which is data superimposed on power. The RS232 converter is very expensive at £150 odd, so I found a circuit to optoisolate and level convert. http://softcircuitry.blogspot.co.uk/2017/03/weighing-lpg-gas-bottle.html