24v vessel charging 12v dinghies.

[chrisblask]

Hi folks!

I have a 24v mothership (Mark Twain) and a 12v dinghy (Old Faithful) both with lithium banks. I'm looking for the system to charge the 12v boat from the 24v boat.

The three components I need to figure out are the charger, the connectors, and if the charger doesn't do it the right 24/12v converter.

My real question is about the charger, if anyone has a recommendation it would be most welcome. This gadget looks like it might fit the bill: https://www.solar-electric.com/me-s...kTFF8zje9YTQb4fpP3QHoXSa12zsWTQhoC2qIQAvD_BwE

Any thoughts on a good marine connector I could mount on the dinghy to plug the charging cable into is also appreciated.

-cheers!

-chris

 

[jwelter99]

Sterling Power 24V to 12V B2B. BB241235.

Will take 24V and charge a 12V system at around 70Ah max.

https://cdn.shopify.com/s/files/1/0658/7343/files/Page20_B2B_1.pdf?4771783895244408190

 

[Alphabavo]

That water is incredibly clear.

 

[snoobler]

Use a constant current buck converter to buck the 24.X down to 12.6 and set your current to charge the smaller boat. Done.

This would result in a never charged 12V battery. 12.6V charge is too low to ever get it fully charged. There are converters that run 13.8V output, and that's enough to get them fully charged, but it takes quite some time.

 

[mikefitz]

The Victron Orion 24/12 charger will be suitable,

New Product: Orion-Tr Smart DC-DC charger - Victron Energy

The new Orion-Tr Smart DC-DC charger is designed for use in dual battery systems in vehicles or boats, where the (smart) alternator and the start battery are used to charge the service battery. The model range is suitable for 12V or 24V systems, and both lead acid and lithium batteries. Why do...

www.victronenergy.com

Mike