How to wire boat dc-dc chargers? Connect in between start and house and in between house and thruster or connect both chargers to start battery pos (or pos bus, which collects all charging sources: alternator, shore charger, solar)?
Hi @Sailor1man ,
Please provide some detail.
Which DC-DC charger are you using?
Details of Battery arrays: Type (LA / LiFePO4), Size(A)
Details of the current charging capability.
Details of the system configuration.
Planning on using Victron Orion-Tr Smart DC-DC Charger12/12 -18
Start will be a flooded lead acid105 Ah @C20 due to outboard alternator output
House and thruster will be AGM Rolls105 Ah @C20
Engine is Honda BF150 outboard, alternator produces at idle speed 13.3 to 14 volts
When running 13.8 - 14.5 volts, Rolls req 14.7-15v for AGM charge, charge at 20 amps, flooded batteries require less volts
30 Amps available at 1000 RPM, 40 Amps available above 2000 RPM.
Shore charger Victron Blue Smart IP67 battery charger Model 12/25
Solar tbd
Positive bus collects all charging sources, then feeds start battery
Is this 1 of each? This is my current working assumption
Also to flag that the Orion needs to be fed from a battery (normally a LA to act as a ‘buffer’ of sorts from the alternator.) The Orion is NOT an Alternator to Battery charger. The Orion is a DC->DC charger.
Alt → LA Batt (normally a starter batt) → Orion 18 → House Batt (LA / AGM /LiFePO)*
Alt → LA Batt (normally a starter batt) → Orion 9 → Thruster Batt (LA / AGM /LiFePO)*
In your senario, I’d be inclined to fit another 12/12 9A for the bow thruster charging
This would maximise your alternator output (30A @ 1000rpm (Orion 18 + 9 = 27A))
You also get some redundancy in the event of an Orion failure (never had one fail yet).
It’s also worth noting that the Orion TR’s can be used in parallel.
Did I mention to fuse as per the manual - FIT APPROPRIATE FUSES IN APPROPRIATE CABLE LOCATIONS.
- Orion configured accordingly - see manual