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12V to 5V
Hanz wrote in
: Spikes: when the batteries goes from 11.75 up to 14.5 volts during normal charging. Maybe 'spikes' is a bad word. But the "buck/boost circuit" of the converter handle it. I don't know of a single piece of marine electronics that won't run just fine on 16-18VDC. "Spikes" are 40V pulses that happen when a battery with a dead cell is charged with an alternator that happens each time the alternator's regulator, trying to figure out why the battery's voltage is only 9.8VDC and charging the hell out of it because it measures deep discharged, feeds full field current to the alternator. You can hear it in the stereo in a vehicle or boat as a loud, high pitched and varying with engine speed, whining in the speakers. You can also see it in any light as you rev the engine and the light gets MUCH brighter, the light bulb averaging out the pulses into an overvoltage condition as the spikes try to blow the filament. A charger will make the stereo speakers hum loudly, VERY loudly if a cell has died into high resistance. The charger's rectified pulses flowing through the dead cell's high resistance (higher than milliohms of a normal cell) create spikes on top of whatever DC voltage the battery actually is. If you're measuring the battery with a meter, the meter movement (mechanical) or a digital meter averaging out the spike during its measurment sampling cycle, don't give you any indication the voltage peaks are actually THAT high. In a cheap boat radio you can hear the spikes, your first indication of either a dead cell or corroded terminals in the charging circuit at the battery, which makes the same whining in the speakers. (42 lurkers have just found out why the stereo is whining every time they crank the beast...(c |
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