Victron Orion smart 18A DC‐DC charger is a 3 stage charger (bulk, absorption, and float) that is capable of fully charging a leisure battery. (Suitable for smart alternators)
 
There is a built-in engine shutdown detection that will stop the charger when the engine is not running. This prevents the unwanted discharge of the starter battery 
 
The charger also has a delayed start, leaving it 2 minutes for the engine starter battery to recharge before it starts to charge the leisure battery, (this can be programmed if your main battery isn't getting enough charge, using the Victron Connect app). 
 
Installation notes
 
Once you've installed it, you need to connect to it with Bluetooth, via the Victron Connect app,  go into the settings wheel in the app and change it from power supply mode to charger mode. Then it will act as an autosensing battery to battery charger for vehicles fitted with a smart alternator. 
 
Never mount the Orion directly above the battery, always point the terminals downwards if possible to prevent water ingress. 
 
Disconnect the green 2 pin plug before you make the connections to the batteries, then re-insert the green 2 pin remote plug to activate the charger. 
 
Please note that the leisure battery should be vented.
 
You will also need a safely secured battery box or battery holder for any batteries you install. 
 
victron manual 
 
Datasheet
12/12 18A model.