Sargent EC155 install

[gazzas1]

Hello all,

I'm looking for any help and advice when installing the sargent ec155, I've read through the wiring diagram and I can understand a majority of it however I'm struggling to see how the connection is made between the ec155 and the leisure battery, the brown and blue wire is the 12v positive in but it terminates at an online fuse how does this connect to the positive terminal on the leisure battery

Any help and advice would be amazing