coulomb
Well-known member
Duh! I assumed that they used a current shunt and op-amp. Hall effect devices are more convenient, but they have that terrible drift problem.GerryAZ said:The Hall-Effect sensor...
Perhaps they figure that they usually only need the current measurement for the first 10 minutes or so of operation, so that drift (usually a slow and steady thing) isn't a problem as they can measure the current when they know it should be very nearly zero, and simply add an offset to the measurement to cancel out the measured offset. Especially since:
I have never seen the charging voltage increase back up to absorption level without turning the car off and back on or turning on the windshield wipers.
If it wasn't for the wipers thing, this would be fine. I wonder if the wipers causing the return to absorb stage was only ever meant as a debugging tool and they forgot to take it out in production, and now find that drivers rely on it. So it remains to this day, I assume.