I have a fairly standard 2 way switch - connects battery 1, both or battery 2. I heed the general advice that if you link two batteries together, the lower-charged one draws from the other.
My question is how long does this take? I sort of assume that it's instantaneous. However that would mean that every time I switched between battery 1 and 2, the discharge would occur when the switch was - momentarily - on "both". I can understand that the reason for the the switch always connecting to a battery is to prevent damage to the alternator, but is the price I pay the fact that I part-
discharge one of the batteries.
Or does the whole process of equalisation take much longer than I believe?