there are two lead 100 Ah batteries on the boat.
So I planned to put an Orion-TR Smart DC-DC charger between the batteries.
Now there are (at least ) three different chargers.
Victron Blue Smart 12v/15A IP 65 CEE 7/17
Victron Blue Smart 12v/17A IP 67 CEE 7/7
Victron Blue Smart 12v/15A IP 22CEE 7/7 (looks much bigger and has more outputs)
how to know if which is the right one and if that will work with the dc-dc charger ?
also I have a Cerbero GX and would preferre no additional bluetooth if that is possible ?
As I am new to all this any additional hint is appreciated
Depending on what you have - and a schematic of sorts would help here:
Assuming one engine starter battery and one house battery (Both batteries with similar voltage requirements):-
you might simplify the situation by using a single dual output ac/dc charger for shore power charging together with an argofet charge splitter from the engine.
In this case no dc/dc charger is required.
If there is a solar charger involved, then an automatic charging relay will sense the voltage rise of the charged battery, and connect the second battery during the charge.
The AC charger though should be upgraded to at least 25A.
needed time for a small drawing . Hopefully explains where I am with the power plannings
so the DC-DC Charger is currently a 18 A as my battery loader was a 10/20 which was good enough so far.
And yes I a solar charger is planned. I have a MPPT 100 / 30 A which I would like to use
In the end would it would mean three power sources (Landside AC, Solar and alternator) and two batteries (Starter, Consumers)
Would the argofet charge splitter still be needed here ?
I hoped actually the dc/dc charger would protect me from that and therefore the starter is always charged first. Especially when the alternator or solar is in use
If that is the case I might do my experiments with solar on the house battery and keep the alternator and the landbased AC charger for the starter battery
still the questions are
what is the right AC loader as in the beginning ?
does the DC/DC charger prevent discharging. And if not is the argofet a better solution (which than would have two power sources if there is no AC load which can load smartly two batteries on a boat!) ?
For 2 lead batteries @100ah you’ll need a 20a charger.
I’d prefer 2 chargers @ 10ah, it will give you some redundancy, also if you’d ever replace the household battery with a lithium you can program seperate load cycles.
you can read my mind
Of course at some point in time a replacement for the household is planned.
from the description it looked like the Blue Smart IP22 Charger could do the job as there could be a version with three exists but not sure if that is a good choice on a boat.
In this case, a standard automatic charging relay would be a simpler solution. You don’t need any voltage difference between the batteries whilst charging, so a dc/dc is overly complicated.
Also, IF/When you change the house bank for Lithium, then the charge voltage levels are very similar to lead, and you can use a BMS driven relay to stop charging and split the circuit when off charge or at full charge.
Actually you don’t even need a relais, i have a diode and a lightbulb between household and starter batteries. When household is more then 0.7v over starter a trickle charge sets in.
Problem with the Diode is that it won’t allow the house battery to charge properly, leading to sulphation. https://www.bluesea.com/resources/1366
should help you understand. The ACR contacts close when the battery being charged exceeds say 13.2V, and connect both batteries in parallel. No voltage drop. There are other methods, but this is the simplest. The problem with DC/Dc is they have constant output voltage, and are not programmable to fall back to a float charge voltage.
