Hey,
Part 1
When running a deep cycle battery, I know that current draw can be used to calculate run time as a factor of Amp Hours of a battery. I also know that batteries should only be drained down to about 50%. So, if I'm running a trolling motor, should I calculate run time assuming that I can "use" all of the amp hours listed on the battery, or just half of these?
According to this site (https://www.trollingmotors.net/blogs/se ... r-run-time), if I have a 100 AH battery and a trolling motor that draws 20 amps, then:
100 amp hour rated battery / 20 amp draw = 5 hour run time
Is this realistic, though? Does this mean that the battery will be dead, and drained below 50% after 5 hrs, or does this mean that after 5 hrs the battery will be half drained?
Part 2
Furthermore, deep cycle batteries usually, if not always, have their amp hour rating determined by continuous load of 5 A/hr over 20 hrs. Whatever the answer to the discharge question above, in order to determine real world working conditions in which I'd draw from 7 to 20 amps, then would I want to use a fudge factor to approximate real world conditions? I know that there are formulas to determine battery discharge at different loads, but these formulas could only get me so far since there are so many variables. If I were to use a fudge factor, what's a good approximation of what value I should use, 25%? 50%?
If I have an motor drawing 15 amps from a 100 AH deep cycle battery at 60 degrees F, am I really looking at about 1.6 hrs run time?
Part 1
When running a deep cycle battery, I know that current draw can be used to calculate run time as a factor of Amp Hours of a battery. I also know that batteries should only be drained down to about 50%. So, if I'm running a trolling motor, should I calculate run time assuming that I can "use" all of the amp hours listed on the battery, or just half of these?
According to this site (https://www.trollingmotors.net/blogs/se ... r-run-time), if I have a 100 AH battery and a trolling motor that draws 20 amps, then:
100 amp hour rated battery / 20 amp draw = 5 hour run time
Is this realistic, though? Does this mean that the battery will be dead, and drained below 50% after 5 hrs, or does this mean that after 5 hrs the battery will be half drained?
Part 2
Furthermore, deep cycle batteries usually, if not always, have their amp hour rating determined by continuous load of 5 A/hr over 20 hrs. Whatever the answer to the discharge question above, in order to determine real world working conditions in which I'd draw from 7 to 20 amps, then would I want to use a fudge factor to approximate real world conditions? I know that there are formulas to determine battery discharge at different loads, but these formulas could only get me so far since there are so many variables. If I were to use a fudge factor, what's a good approximation of what value I should use, 25%? 50%?
If I have an motor drawing 15 amps from a 100 AH deep cycle battery at 60 degrees F, am I really looking at about 1.6 hrs run time?
