question

richardb26 avatar image
richardb26 asked

What battery amp hours are used for a system setup BMv 712

What figures do I use in my set up if I have two 105 amp hour batteries for my house batteries and one 130 amp hour starting battery. Do I use the total figure of 340 or just the 210 amp hours of the house batteries

BMV Battery Monitor
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2 Answers
kai avatar image
kai answered ·

210AH. Assuming that your starting battery is wired separately, and your 2x 105AH batteries are in parallel, not series. The BMV only needs to understand the capacity of the battery bank that is directly measured by the shunt.

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David avatar image
David answered ·

As Kai says, add up the AHs when the batteries are in Parallel, but not if in Series - so it these are a pair of Trojan 6V T105s for example, you would put in 105 rather than 210.

Also, the BMV wants the AH total for the "C20" rating to be entered. Lots of batteries are quoted at the C100 Rating for marketing reasons as it makes them seem bigger. Check the 105 is for the C20 number (or look for the C20 value if not).


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