Author Topic: Sizing a 12 Volt Battery to a load online alulator  (Read 864 times)

Offline Greekman

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Sizing a 12 Volt Battery to a load online alulator
« on: March 20, 2018, 01:11:35 AM »
just found this.
https://www.batterystuff.com/kb/tools/calculator-sizing-a-battery-to-a-load.html

it gives off quite scary (large) numbers but it cannot be wrong. Can it?

Offline Alan Georges

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Re: Sizing a 12 Volt Battery to a load online alulator
« Reply #1 on: March 20, 2018, 06:46:43 AM »
it gives off quite scary (large) numbers but it cannot be wrong. Can it?
It seems pretty close to the numbers I get for typical cases.

They seem to be using the "daily load x 4" rule.

Offline fratermus

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Re: Sizing a 12 Volt Battery to a load online alulator
« Reply #2 on: July 07, 2018, 08:25:19 PM »
It's correct.  Note the language near the bottom;  when one understands what they are saying then it's just math:

Quote
Battery Needed is rounded to nearest whole number, and is rated in AH at a 20 Hour rate. If you find a battery with at least this many rated Amp Hours Your Load will run for the desired amount of time at a safe 50% discharge level

Here is some info on how lead-chemistry batteries are rated
Here is some info on depth of discharge.

Offline Carl

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Re: Sizing a 12 Volt Battery to a load online alulator
« Reply #3 on: July 08, 2018, 06:35:11 AM »
  Batteries are only chemical storage of energy and not nuclear so often people discover the old adage that solar /battery power is about using LESS energy and conservation.