On 26/04/2021 16:33, Chris Green wrote:
I agree, somewhere around 14.5v is the terminal (as in final) voltage
to fully charge a nominal 12v lead acid battery. The charger should
then drop back to something like 13.5v, 'float' voltage, to maintain
the battery.

The exact voltages will vary with temperature and the exact type of
battery.

Yes, I think I'll check the voltage with an accurate meter tomorrow. It
does seem high. Of course it's the output from a 24/12V converter. Oddly
it takes a long time to charge the battery, always has done, and does
now with a new battery.