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electrical:depth_of_discharge [2020/06/23 10:55] frater_secessus |
electrical:depth_of_discharge [2021/02/21 13:33] frater_secessus [SoC by voltage] |
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- | | **DoD**| | + | | **DoD**| |
| 10| 90| 22.5| | | | | | | | | 10| 90| 22.5| | | | | | | | ||
| 20| 80| 45| 3000| 135| $1.93| | | 20| 80| 45| 3000| 135| $1.93| | ||
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==== SoC by voltage ==== | ==== SoC by voltage ==== | ||
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+ | Note: read [[https:// | ||
100% SoC (~12.7v) is measured [[electrical: | 100% SoC (~12.7v) is measured [[electrical: | ||
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* constant light loads with measured >=12.2v | * constant light loads with measured >=12.2v | ||
* intermittent heavier loads that leave the system with measured >=12.2v when that load is removed | * intermittent heavier loads that leave the system with measured >=12.2v when that load is removed | ||
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+ | The more challenging task is judging when to kill the circuit based on voltage **under heavier loads**. Consider this chart: | ||
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+ | {{ https:// | ||
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+ | For a 200A bank 50% DoD would be 12.1v at rest, ~12.0v at C/10 (20A discharge), ~11.55v at C/5 (40A discharge), and 11.2v at C/3 (~70A discharge). | ||
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+ | It may take experimentation with your system to see where the battery voltage rebounds after removing the heavy loads. | ||
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+ | - apply expected load | ||
+ | - run battery down to 11.5v (then 11.25, 11, 10.75, 10.5 etc until battery no longer rebounds to 12.1-12.2v) | ||
+ | - remove load | ||
+ | - observe battery voltage | ||
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+ | If the battery rebounds to the desired voltage then repeat to deeper discharge. | ||