split charge relay
Posted: 31 May 2006, 21:00
my leisure battery is not charging, what ampere rating relay will i need? will 80a suffice? ta
are you changing your relay or fitting one?
If you are replacing check your fuses first (there should be one on each battery) as that is more common than relay failure.
If fitting a new one, I use the 40A ones from breakers normally used for horns etc. so 80A should be fine.
Two things to bear in mind - under normal conditions your alternator output will be shared between the batteries so "about" half the alternator output will flow onto the leisure battery.
However, if one battery is flat and one full the more charged battery will try to charge the flat one - and this does create large currents. Its not clear how long this surge lasts for but does account for a lot of blown fuses after festivals!