Sailboat lifepo4 2x200A set-up - Schematical drawing and interrogations

[Dijo]

Not quite. You *always* need a regulator of some kind for an alternator. The alternator simply will not work without one. But, you could use a cheap alternator with an internal regulator, or a cheaper external alternator. You wouldn't need an expensive regulator that is safe for Lithium. The alternator would be connected to the Lead Acid starting battery as if it were the only battery you had. Then the DC-DC charger would charge the Lifepo4 from the Lead Acid battery. So the Lithium battery is isolated both from the other battery and from the alternator.

This is a common and recommended setup for a number of reasons. The downside is that you will only be able to charge your Lithium Battery at the rating of the DC-DC charger - typically 30A.

Allright ! seems ok to charge only 30A as it won't be my main charge system.. is the Renogy DCC50S 12V 50A, which allow you to pull 50A is not better than the Victron ?
Something i don't fully understand with the renogy is : could be use as mptt and DCDC charger at the same time or it's juste a DCDC charger with MPTT integrated

 

[wholybee]

Most people feel Victron is a higher quality than Renogy, but many like Renogy also. Yes, that model is both a DC-DC charger and an MPPT solar controller.

 

[Dijo]

Most people feel Victron is a higher quality than Renogy, but many like Renogy also. Yes, that model is both a DC-DC charger and an MPPT solar controller.

are you sure ? because on their website they say :"Designed to charge service batteries from two DC inputs-the starting battery or solar panels"
what does the "or" mean ?

If it the case, i could not buy my mptt epever 40A and go for the DCDC RENOGY 50A.. But i can't find if it's 50A MPTT..

And also they say : "

• Trickle charges the starting battery via solar panels if the service battery is fully charged."
  
  What does that mean exactly ? than solar won't be alway charging my service bat ?

 

[willo]

Add a precharge circuit to that lifepo4 facing cutoff switch to prevent arcing - even when the inverter is off, the capacitors on the input side are in play.

 

[mikefitz]

I'm a new member here with a solar system on my sailboat

To avoid confusion I suggest you copy your post , delete the content and post a completely new thread.
Mike

 

[Bubba1]

To avoid confusion I suggest you copy your post , delete the content and post a completely new thread.
Mike

Agree. Start your own thread and you will get response. I see a few things I would change.

 

[SV Lyric]

Agree. Start your own thread and you will get response. I see a few things I would change.

To avoid confusion I suggest you copy your post , delete the content and post a completely new thread.
Mike

thank you. I have moved it to "lifepo4 independent and combined battery banks"