im sorry you guys must be getting sick of being asked about this.
ok, searched the forum again and came up with a bit more info i missed the first time.
i want a spare battery to run my 'luxuries' off of. always been afraid of engine not starting due to drained battery, so i thought the best option would be to install a second one.
i understand most of the diagram in this post
http://www.fordtransit.org/forum/viewtopic.php?t=7098&highlight=twin+batteries but a wee it pickled about the 'charge indicator' bit,
using a relay i fit the 2 lives of the battery together?
and then wire from the altenator to the relay?
earth the relay and second battery?
so whats the charge thing about?
thanks for your help guys, i feel bad about asking so much so soon on the forum!