Which leisure battery? v??? ah??

[SPCleaning]

But you don't need to disconnect. Mine is always working.

 

[Clearview Lee]

Ok fair enough. Thanks again.

 

[Aqua-pure Portadown]

I have the same fitted in my van ( only mines called a split relay ) it only starts to charge when the van is running ,it's needs the start up power to kick start the relay so it won't run your van battery down when not driving great job