I've used one of these with an additional inline fuse 300mm away from the leisure battery suppling the aux fuse box. http://www.autoelectricsupplies.co.uk/product_list/63
I got the continental type so my fuses are all the same and also the connector bar. So the feed from the battery goes in the bottom left terminal through a 25 amp fuse then the connector bar is fitted along the top row so that the main feed goes through the 25a fuse to make all the top row live. The supply to all your lighting, hifi, water pump etc are taken from the bottom row of terminals with appropriate fuses in between.
This is what we did as well.Did a bit of fiddling so we can switch from leisure battery to hooked up 12v supply.
I've written a whole how to, well not strictly a now to more of a plan, diagram and what kit you'll need with guidance. It's somewhere in TLB, I'm on tapatalk so can't easily search for it. You might have better luck than I, its something like 240v hookup, leisure battery wiring diagram.
I've got one just like that in my house, a bit of a bother to put it in the van everytime i want hook up
I followed madfrankie's and matty's excellent how to's with the exception that I went for a Durite heavy duty voltage sensitive split charge relay which seemed to be simpler - I like to keep things simple. No need for boat or zig panels. I used a continental type fuse block along with a built in charger Ctek 5 and split charge relay which sorts everything out automatically. I also used the neat little cbe socket units, the flap in the centre is hiding a 12v supply socket:
Looks very neat.We used a boat unit so I could isolate the toilet,lights,sink and propex simply in the Jurgens.Oh and to cover a huge hole cut into the furniture by the PO.
