Forum Discussion
road-runner
Sep 13, 2017Explorer III
When working with different voltages you need to think in terms of power. For example, 13.3 amps at 120 volts is 1596 watts (volts * amps). The charger converts that power to, say, 14.2 volts, and you can find the current at that voltage and power, which is 112.4 amps (watts / voltage). Run that for an hour and you've added 112.4 amp-hours to the battery.
In reality it's not quite that simple. The charger is less than 100% efficient in its voltage conversion. Not knowing the exact efficiency, 85% is a reasonable guess, so that 112.4 amp output becomes 95.6 amps. It's unlikely that your battery will draw that much current for an hour, so you won't even be able to add 95.6 amp-hours in an hour. If your charger wasn't power factor corrected there would be another output reduction, but you don't have to worry about that one.
In reality it's not quite that simple. The charger is less than 100% efficient in its voltage conversion. Not knowing the exact efficiency, 85% is a reasonable guess, so that 112.4 amp output becomes 95.6 amps. It's unlikely that your battery will draw that much current for an hour, so you won't even be able to add 95.6 amp-hours in an hour. If your charger wasn't power factor corrected there would be another output reduction, but you don't have to worry about that one.
About Technical Issues
Having RV issues? Connect with others who have been in your shoes.24,193 PostsLatest Activity: Jan 27, 2025