Charger auto-shutoff
Folks,
Something I'm going to see if I can brew up is a charger that automatically disconnects (if desired, depending on settings) when the charger power consumption rises a bit, suggesting full sticks.
I use a Kill-A-Watt to track charger power consumption and (including the backyard fountain) the power will stay at 72W and then eventually gradually rise to 74 or 75W before slowly descending down to 15W if not lower (I know from a forgetting to unplug it). There has to be a way to detect that peak in the power consumption, leading to tripping out of its own power source.
It should probably be voltage-based, since the current doesn't change from 350mA until the pack is beyond the voltage dip. It could however detect a post-dip current drop below 350mA, either via the voltage across a shunt resistor or via an R-C circuit noticing a negative voltage slope across the shunt resistor.
Having it essentially automatically unplug itself at just the right time would be great, IMHO, for unsupervised charging. If op-amps can reliably trip with millivolt-level sensitivity, not only could the charger go from high current to low at the right point, but also take it a further final step by disconnecting completely at just the right point.
It's something I'll see if I can develop, so perhaps my role here can extend beyond asking questions. ;>
Roger
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Silver 2000 5spd Insight
218,000 mi.
55 - 76 mpg
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Action without philosophy is a lethal weapon; philosophy without action is useless.
- Soichiro Honda
Last edited by crx_rogus; 03-25-2010 at 01:10 PM.
Reason: CC factors
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