12volt DC vs 120volt AC question
I'm new to this RV stuff so bear with me and what is probably a very elementary basic question. I have many lights in my interior coach that are 12volt DC fixtures. I know when the coach is turned...
Forum Discussion
Hi,
The battery stays in the "Loop". However it is not typically supplying power while plugged in or running the generator.
What happens is the converter/charger can put out up to about 45 amps (might be a 55 or 60 amp model?). If the battery is really low, it will accept most of that power. If you are running 10 amps of lights (about 9 of them) then the charger will supply all 10 amps + have about 10 more amps to run things like the refrigerator circuit board, furnace, water pump, ect, and still have another 25 - 45 amps available to recharge the battery. The battery might not be in the mood to accept all 25 amps. Once the battery voltage is around 14.0 volts, the amperage into it will drop a lot. So it is like a frog jumping 1/2 way to the end of a log. THe first steps are large ones, but get smaller as the frog is closer to the end. Charging a very dead battery, it will accept a lot of power quickly, but will slow it's charge amperage as it gets up to about 80% full, and might take 1 hour to put in 40 amp hours when 40% full, and take 3 hours to put in 40 amp hours when 85% full.
It is best to keep the battery as full as possible - at least in the 50% to 80% full range. At least once a month recharge by plugging into shore power, or run a generator for 4+ hours to get the capacity up above 95% full. Also check the water level every couple of months if you are using it regularly.
So no- the battery should not be supplying power while plugged in. However it can. Lets say you have a sudden need to run 30 lights, the furnace, and water pump. This 48 amp load is more than a 45 amp converter will supply, so the battery will supply the balance, about 3 amps in this case.
Fred.
The battery stays in the "Loop". However it is not typically supplying power while plugged in or running the generator.
What happens is the converter/charger can put out up to about 45 amps (might be a 55 or 60 amp model?). If the battery is really low, it will accept most of that power. If you are running 10 amps of lights (about 9 of them) then the charger will supply all 10 amps + have about 10 more amps to run things like the refrigerator circuit board, furnace, water pump, ect, and still have another 25 - 45 amps available to recharge the battery. The battery might not be in the mood to accept all 25 amps. Once the battery voltage is around 14.0 volts, the amperage into it will drop a lot. So it is like a frog jumping 1/2 way to the end of a log. THe first steps are large ones, but get smaller as the frog is closer to the end. Charging a very dead battery, it will accept a lot of power quickly, but will slow it's charge amperage as it gets up to about 80% full, and might take 1 hour to put in 40 amp hours when 40% full, and take 3 hours to put in 40 amp hours when 85% full.
It is best to keep the battery as full as possible - at least in the 50% to 80% full range. At least once a month recharge by plugging into shore power, or run a generator for 4+ hours to get the capacity up above 95% full. Also check the water level every couple of months if you are using it regularly.
So no- the battery should not be supplying power while plugged in. However it can. Lets say you have a sudden need to run 30 lights, the furnace, and water pump. This 48 amp load is more than a 45 amp converter will supply, so the battery will supply the balance, about 3 amps in this case.
Fred.
