Battery draining question
I'm pretty new to RVing. We have been inveterate tent campers, but last fall purchased a used '07 (or '05 - somewhere around there) hybrid travel trailer (Jayco JayFeather 19-H) so I'm pretty new to ...
Forum Discussion
my frig on propane only uses 0.30 Ah which to me is not much.
Of course you mean amp hours per hour or just amps. Sorry to be picky but we are trying to help someone understand how this all works.
Our fridge draws 0.4 amps all the time - about 10 amp hrs per day. That alone takes one 80 amp-hr 12 volt battery down to the dreaded half full level in 4 days. Note that if using 6 volt batteries, it takes 10 amp hrs out of each battery because they are in series and the same current goes through both - so you need twice the amp hr rating on 6 volt batteries to provide the same energy. I think misunderstanding this fact is the source of the belief that 6 volt batteries have greater energy capacity than 12 volt ones. The misunderstanding is in the units on this, too. The amp hour is a unit of charge, equal to 3600 Coulombs. Energy is measured in watt-hours or volt-amp-hours so you must multiply your battery's amp hour rating by its voltage to get the energy capacity. A 12 v, 80 amp hr battery has the same 960 watt hour energy capacity as a 6 V, 160 amp hr battery.
We share your desire to boondock without a generator. We just did 5 days on two batteries with a two hour drive in the middle that restored about 20 amp hrs according to my little battery monitor. I worked hard on the connections to get engine charging to work that well, just half a volt lost between engine battery and house battery when the engine is running. I will soon have 100 watts of solar charging to extend our boondocking time. Battery monitor thread
Of course you mean amp hours per hour or just amps. Sorry to be picky but we are trying to help someone understand how this all works.
Our fridge draws 0.4 amps all the time - about 10 amp hrs per day. That alone takes one 80 amp-hr 12 volt battery down to the dreaded half full level in 4 days. Note that if using 6 volt batteries, it takes 10 amp hrs out of each battery because they are in series and the same current goes through both - so you need twice the amp hr rating on 6 volt batteries to provide the same energy. I think misunderstanding this fact is the source of the belief that 6 volt batteries have greater energy capacity than 12 volt ones. The misunderstanding is in the units on this, too. The amp hour is a unit of charge, equal to 3600 Coulombs. Energy is measured in watt-hours or volt-amp-hours so you must multiply your battery's amp hour rating by its voltage to get the energy capacity. A 12 v, 80 amp hr battery has the same 960 watt hour energy capacity as a 6 V, 160 amp hr battery.
We share your desire to boondock without a generator. We just did 5 days on two batteries with a two hour drive in the middle that restored about 20 amp hrs according to my little battery monitor. I worked hard on the connections to get engine charging to work that well, just half a volt lost between engine battery and house battery when the engine is running. I will soon have 100 watts of solar charging to extend our boondocking time. Battery monitor thread
