Battery Monitor installation question

[john61ct]

Originally Posted by Boatwright

As I understand it the SmartGauge system monitors voltage patterns over time and uses a computer algorithm to "deduce" SOC. It does not directly measure amp/hours (Coulumbs).

Yes, not relying on AH counting is why SG is more accurate.

No one but Gibbo the inventor knows exactly how it works, but it is definitely measuring more than voltage, the speculative explanations I've read are way over my pay grade.

[Boatwright]

If you really want to get into the subject I have relied on the following article:

https://pssurvival.com/PS/Batteries/...ltage_1993.pdf

Notice the "C/xx" at the right side of each curve. This is to match the particular curve to the rate of discharge / charge in Amps for a given battery capacity.

This is explained in detail at the bottom of the first page (#67).

I suspect that this model is the basis for any non- AH measuring battery monitoring system. One can see, with a bit of study of one's own system, it is possible to accurately judge the SOC of lead acid batteries with a good voltmeter and a bit of knowledge about the Amperage loads of the boat's equipment. It works for us.