4 ms·
An RTC chip without temperature compensation in an extremely variable temperature environment.
by pstrateman 8y ago
An RTC chip without temperature compensation in an extremely variable temperature environment.
- sokoloff 8y agoHow far would a lighting control or HVAC control have to drift before it became impractical to use? I could imagine 45 minutes could still be “eh, who cares?” 45 minutes in a year is under 1 part in 10000.
- TylerE 8y agoI can imagine 5 minutes being well into I care territory. Could be the difference, say, between pulling into a dark drive way or having light.
- sokoloff 8y agoProgram the lights to come on 30 minutes earlier then. An overcast day and a new moon vs a day with high cirrus overhead and clear skies to the west almost surely has more variability than 5 minutes' difference.
- TylerE 8y agoIf it drifts at 5 minutes per week you still have to reprogram after 6 weeks.
- sokoloff 8y agoSure, but that's ~500ppm drift, which is fairly extreme.
- freeone3000 8y agoHT1380 drifts 10 seconds every 20 hours under normal conditions. I don't think this is outside the realm of possibility if they chose a cheaper chip or had weird temperature fluctuations.