On Tuesday 05 Feb 2013 23:25:15 James Courtier-Dutton wrote: > The 1 wire therm is a good idea. The fewer moving parts the better. > With therm sensors rather than on/off at particular temp, i can make the > heating system better. I.E. When in heating hours, heat normally, when out > of heating hours, make sure the system does not freeze. I don't need to > adjust the heating with a stat dial on the wall, i can use a smart phone > app. > I still wish to detect 240V AC because that will help with fault finding. > The system could do analysis for me and tell me which part has failed. I > think the ADC would be good for that. > Example diag: > 1) Turn burner on and send heat to the HW. If the HW temp does not rise a > bit, something is wrong in that part. > 2) If the burner is on but the HW temp is still falling. The sensor is Ok, > but something else is faulty. > 3) If different power is sent to the diverter valve, does the orange output > change as expected. Points to working valve or not. > 4) Measure current and volts to the pump. A pump should always draw a > predictable amount of current when on. If not, faulty pump.
Have a look at: https://github.com/TimB- QNA/Electronics/tree/master/RaspberryPi/InvestigationBoards/SPI_ADC I will add some code to read/write all the stuff on that board at some point (all written as it is, just not tidy!). You can adapt pretty much everything there for your purposes. Given that the DS18B20 has a unique ID per chip, you could also use them locally around the boiler. Tim B. -- Hampshire Linux User Group Chairman -- Please post to: Hampshire@mailman.lug.org.uk Web Interface: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG URL: http://www.hantslug.org.uk --------------------------------------------------------------
