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bonsys asked

Should MultiPlus temp compensate in Absorption mode?

MultiPlus-II (firmware version v506) with the charge profile configured in AGM mode with -18mV temp compensation does not increase absorption voltage to compensate for the battery temperature at 14 degrees. Why?


14.7V + (-0.18V x (14C - 25C)) = 14.7V + (-0.18V x (-11C)) = 14.7V + 1.98V = 16.68V


I am not observing expected 16.7V at all. Instead the MultiPlus-II is hovering around predefined 14.7V without temp compensating.


In which mode temp compensation should be applied: bulk, absorption, float?

screenshot-2023-09-21-100849.jpgscreenshot-2023-09-21-100921.jpg

Multiplus-IIAGM Batterytemperature compensation
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screenshot-2023-09-21-100849.jpg (19.1 KiB)
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1 Answer
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pwfarnell answered ·

Your maths is wrong, the effect is much smaller than you have calculated.

14.7V + (-0.018V x (14C - 25C)) = 14.7V + (-0.018V x (-11C)) = 14.7V + 0.198V = 14.898V == 14.9V.

18mV is 0.018V. You calculated using 180mV.

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Related Resources

MultiPlus-II Product page 

MultiPlus-II Manual

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