Has anyone had success using 10K thermistors with this plug in. I have been messing with it all day and cant seem to figure out how to turn the returned value into something usable.
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Typical voltage divider network with a fixed 10k at the arduino and the thermistor in the room being monitored. The 1-wire solution just does not work well unless I rewire the 12 rooms. everything is home run in a star configuration.
The raw values coming back from the circuit are accurate and can be manipulated from 0 to 1023 using a decade box.
I played with a few values in the sum field and ended up with Value/6.75 and the thermistor seems to track properly in an ice bath as well as up to and above room temp when compared to a 1-wire probe.
Either I am over thinking the solution and the math is accurate or I just got really lucky
If you have any ideas on how to get the 1-wire to work in a star, let me know. I have 2 dozen 1-wire sensors in hand ready to go.
FYI 1 wire sensor is US $1.50 and a 10k thermistor is $0.50
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i have 13 onewire in star configuration and it work good
only thing you need is 3 wire at each probe , maybe you have only 2 ?
then at the central point you put your 12 positive wire together
your 12 ground wire together
your 12 data wire together
then you connect it like it is only ONE probe and it must work (need only one 4.7K resistor between data line and positive)
connect ground to ground on arduino , connect positive to 5v on arduino or from external 5v power supply (dont forget to connect commun ground if using power supply) , connect data line to the pin set in the plugin
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