The banks have 2 separate double pole switches, until now in order to
charge the domestic batteries there has been a link between the 2 negative
poles on the switched side of the switches.

Surely all that is doing is connecting the battery earth which is the system
earth... how is a positive charge from the alternator etc able to charge
through this link.... I'm confused.


I brought a VSR (voltage sensitive relay) to replace this link, but when I
came to fit it I found that it needs to connect between the 2 positives of
the battery banks. So I plan to buy another relay (an ordinary one), wire
it in the link currently joining the 2 banks, and then, use my VSR to
switch this relay on and off. Does that sound sensible or have I lost the
plot.

Yes it would do the same job but I still don't get it.

Brian