DS18S22 resolution and meta point trouble

I have some questions. Is that possible to increase resolution of 1-wire temperature measurements? Now that is 0,5 C. I calculate status of hot water making. (p15= hot water temperature)

if ((p15.value-p15.ago(MINUTE)) <= 0.1)

return false;

return true;

See attachment of this message. That red curve in upper picture is hot water “ON”. When somebody uses hot water, that curve will goes up and down, up and down. I will put that comparison value 0.1 but if that temperature moves 0.5 C steps, that doesn’t working correctly.

Another trouble is that blue curve. That is status of geo heatpump “ON”. I calculate that on formula:

if (p40.value <= 0.5)

return false;

return true;

p40 is momentary power and that is calculated by formula:

return (p39.value - p39.ago(MINUTE))*60/1000;

p39 is pulses from that dual counter.

On that lower picture, red curve is pulses from counter. That will go nice. I wonder why that blue curve drop down even thought pulses goes nice. If I look numbers of pulse values, they go nice. Every new value is bigger than old value. I try to explain those blue curve “peak” clocks 0:00 and 6:10, after 10:30 it’s seems to be okay.

Hi Antsu,

I think the 0.5C resolution of the temp sensor is a 1-wire restriction. The documentation on the units that i have say so - not sure about yours.

Re the blue curve, i suspect those drops at midnight and 6:30 are due to your function momentarily returning "false". I suggest doing an analysis on the data to find out for sure.