Dry camping with furnace on
I was dry camping this weekend and had to put the furnace on for the first time. I was worried that I would kill the battery if I ran the furnace overnight. I was right :(. The house battery was ...
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They really should come with a battery my monitor.
Heating varies tremendously among people. DW and I rarely have the heater on for sleeping. And we camp in western Canada, often in April and October.
Yes a bit of jumping to a conclusion from the measurement showing that the voltage at full charge was more than 0.3 volts higher than the voltage chart for quite a while. Maybe it wouldn't be so bad at half charge. Someone should check.
"And lastly, what do you think your "battery monitor" has to go by in estimating the state of charge except voltage ? It doesn't have a specific gravity probe into the acid does it ?? "
A battery monitor reads the current going into the battery and coming out. This is multiplied by the time duration to get the number of Coulombs or amp-hours of charge in and out. The count is updated every second or so, maintaining an always accurate count of the number of amp-hours stored in the battery.
I get your idea of a load clearing the surface charge more quickly. But how quickly? Someone with a battery monitor ought to do a graph with a load showing the voltage and the % of full charge over time. It would have to be done for various currents to get a full picture. It is all very complicated to tell the state of charge from voltage. The OP and I are two of many people who ruined batteries by trusting the voltage chart for state of charge.
Heating varies tremendously among people. DW and I rarely have the heater on for sleeping. And we camp in western Canada, often in April and October.
Sam Spade wrote:
Also I don't understand your logic in saying that a battery that reads 12.6 volts could be half charged.
Yes a bit of jumping to a conclusion from the measurement showing that the voltage at full charge was more than 0.3 volts higher than the voltage chart for quite a while. Maybe it wouldn't be so bad at half charge. Someone should check.
"And lastly, what do you think your "battery monitor" has to go by in estimating the state of charge except voltage ? It doesn't have a specific gravity probe into the acid does it ?? "
A battery monitor reads the current going into the battery and coming out. This is multiplied by the time duration to get the number of Coulombs or amp-hours of charge in and out. The count is updated every second or so, maintaining an always accurate count of the number of amp-hours stored in the battery.
I get your idea of a load clearing the surface charge more quickly. But how quickly? Someone with a battery monitor ought to do a graph with a load showing the voltage and the % of full charge over time. It would have to be done for various currents to get a full picture. It is all very complicated to tell the state of charge from voltage. The OP and I are two of many people who ruined batteries by trusting the voltage chart for state of charge.
