question

Ηi! How are you charging the batteries? Do they finiah there absorption charge? Do you equalize them every 20-30 days? If not your batteries are slowly degrading.

Hmm.

Equalizing should be monthly, but I have not seen any sign of it recently (scarce sun);

Charging with victron blue solar MPPT. Rare absobtion finishing (scarce sun)

During sunless 3 days, SOC went down 3% with consumption 2kWh. With 24V batts that would make a capacity between 42 and 100 kWh (or 1876 to 4167 Ah) for a official 1714Ah C120. Am I wrong somewhere?

Thanks for your tips.

Lionel

Hi @Lionel SEYDOUX

Those voltages on a 24V lead-acid battery = a very empty battery!!

This is very harmful, I advice you to get your installer to check the system.

Your battery monitor is probably not configured correctly leading to a reset to 100% SOC long before the battery is charged. (or it is not installed correctly)

If you have a generator, I'd run it for a long time so the battery can get fully charged and equalized.

Thanks Dan !

In understand my 10 years old lead bats are done, but dont understand why no warning... I shall have to wait afew months before havin a look: about 2m snow, 3 hours to climb up with snox shoes. Safety is OK with a limestone pit under the batteries, but presently I am at -2°C. Will see and report as soon as possible.

Hi Daniël

I shall see to that BMV when I manage to come up there (no lift, 1m snow...) but un June, same settings I never came uneder 24.7V ar the end of the night.