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Showing posts with the label #lifespan

Battery life of the 1byone Driveway Alert Sensor system

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This information would be good to know for anyone considering this system, but does not seem to be available. I measured two sensor samples as follows: -  Standby (active):  25 uA max -  Detect:  16.2 mA max for about 2 seconds It's not actually 16 mA for the full 2 seconds, but that's close enough.  Especially since the 2 seconds might be anywhere from 1 to 3 seconds - I did not bother to measure more accurately than that. The sensors run on AAA cells, which I personally hate because of their relatively low capacity.  But, running the numbers, the effective capacity of AAAs should run these sensors for a very long time. Assumptions: -  Due to self-discharge and temperature effects, cells will only deliver 75% of their rated capacity. -  I estimated alarm consumption at 16 mA for 4 seconds.  This is twice as conservative as the ~2 seconds I estimated from observing the unit current. These work out as follows: Using 1000 mAh ...