Green Living
ISDN2001/2002: Second Year Design Project
Technical Independent Study
Implementation: Accurate lifetime prediction
by Hardy FAN
Background
1. Lifetime of devices are calculated through approximation
2. Continuous measurement may not reflect reality
3. Devices are replaced based on installation time not operation
Study approach
How can exiting sensors in a smart home system be
utilised to maximise the benefits for hotel by reducing
waste and minimising the cost of replacing devices?
L70/L80 Figure
L70 || L80 is a measure of the expected number of operating hours until the light output of an LED luminaire diminished to 70% or 80% of the initial level.
Conclusion:
L70 || L80 is a measure of the expected number of operating hours until the light output of an LED luminaire diminished to 70% or 80% of the initial level.
ARL
The Average Rated Life(ARL) is how long it takes for half the
light bulbs in a test batch to fail.
Real time calculation:
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Illumination sensor
Microcomputer
We simulate the using situation in hotel room. Turn on light bulbs 12hours per day and record the diminished trend.
Result
