question

kaeser-sosae avatar image

Bulk/Absorb Voltage disregarded

Hi Brains Trust,

My MPPT 100/30 seems to be ignoring my Bulk/Absorb settings. I‘ve got absorb set at 14.4v which is my battery manufacturer’s recommendation.

Yet, in Bulk and Absorb mode, it’s sits around 13.5v.

Screenshots attached. Am I missing something?

Cheers

Gavin

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48e926f9-1024-4df8-852d-da0d062c4be8.png

battery charging
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1 Answer
Paul B avatar image
Paul B answered ·

In my opinion - It just means that the battery has NOT been fully charged yet to 14.4v - or you are using more power over the day than the mppt produces

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I've been monitoring this for a couple of days. I think you are right. The voltage does slowly increase. The batteries have 240Ah of capacity, so the voltage curve will be very flat for most of that capacity, until it is fully charged.


I just would have thought that to reach the 14.4v, it would need to be putting in 14.4v to the batteries to get there. Wouldn't this then show 14.4v at the terminals while it's charging? Maybe not... I'm a little new to this.