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Old 11-28-2024, 09:55 PM
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Quote:
Originally Posted by getty150 View Post
... The third category pictured above is really Reserve Capacity commonly listed as RC ?
Nope - but it's similar. The 20HR capacity rating is simply stating that this battery should be able to deliver 5amps for 20 hours, before reaching it's terminal voltage (10.5v)

100AH divided by 20 hours = 5amps

The Reserve Capacity of a battery is the number of minutes the battery can supply a known current (usually 25amps) before reaching 10.5v.

In a perfect world, a 100AH battery could sustain 25amps for 4 hours but as batteries are not perfect voltage sources and have losses that increase with factors like loading and temperature, a good 100AH battery is more likely to have an RC of 150-200 (minutes).
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