Hi Jacques,
Merci, yes I have been considering something like you suggest, using
python to calculate the delta-time more accurately than using NOW in
the CDEF or storing the power in the rrd database at data capture time.
Finally I ended up improving the data capturing timing (on an Arduino)
to pro
Hi
If I understand you correctly….I think you’re having issues trying to use NOW
because rrdtool will snap to the 1 second grid skewing your calculations ever
so slightly. I don’t think it’s really designed for that. It would probably
expect DEF like ( TMPOUT, TMPIN, AMOUNT_OF_WATER) and then j
I have a simple application to determine the power generated by a water
heater. One sensor (TEMPIN) measures the in-flowing cold water temperature
while a second sensor (TEMPOUT) does the same for the hot water exiting the
heater. The flow rate is constant and samples are stored in an rrd database.
