Don't get me wrong.....I enjoy a good pi$$ing contest as well as the next cowboy. I certainly don't intend to hurt the feelings of those who worship at the altar of High Tech, and this is probably more telling of my dinosaur status in life! ? Now don't get me wrong, I do love my integrated navigation electronics, but I also keep my lead line and sextant aboard and know how to use them.[emoji6]
But this old NPR (Nuclear Power Retiree) still monitors battery health aboard Salty with a digital voltmeter, hydrometer and thermometer. I guess 40 years of weekly/monthly/quarterly survelance testing/trending of individual cell voltage and specific gravity on battery banks the size of a boxcar, may have warped my thought process ?. Of course, being blessed with the spacious engine room of a DeFever, spending quality time with my house battery bank is not the chore some may have to endure[emoji6].
For what it's worth, I have a pretty good idea how many days we can hang on the hook and not draw our 1300AH house bank below 50%. So when my total bank voltmeter gets anywhere near 12.2V, I step into the engine room and verify that the SG of the Pilot Cell battery hasn't dropped below 1.190 (temperature corrected). The Pilot Cell (weakest 6V battery) is established during monthly battery testing, by trending the individual battery voltages and SG readings.
This dog may not hunt for some folk's power requirements/time spent at anchor.... But with my wife's obsession with hot showers in cooler temps, our normal generator run time (with 100Amp charger/inverter) has always maintained the bank at 60-75%, and we regularly spend a week at our favorite ancorages.
I guess my viewpoint is that if you install an adequate size house battery and charging capability, then you can spend more time catching redfish and drinking bourbon, and less time obsessing over 1/100th of an amp-hour! ??
KISS!