I am in search for ideas on how to do something without spending too much?
The scenario:
On my boat I do run a complete Victron installation
2 Smart LFP with 200Ah each, in parallel
Lynx BMS
Cerbo GX
Orion Xs to charge the starter and windlass batteries
Multiplus II for getting 230 V and, if on landpower, nearly never happens, charging
Normal charging done with three Smart MPPT (one for each set of panels).
I now think about adding another battery to the system that shall ONLY rin the 2way radio. Battery will be stored very high in the boat so that the Radio still fumctions if boat is half full of water. This battery shall be around 20Ah. Best guess is a Victron SuperPack battery.
But how to make sure that
a) the battery is charged from house side and
b) not discharged by anything else than the radio?
I know that I could buy a second Orion XS but are there “cheaper” alternatives?
Consider the Victron Orion 12-12/18 isolated. This is cheaper but at 18A output is just above the 15A max continuous charge current listed for the 29Ah battery and unlike the Orion XS does not have a current setting. But as it will be just keeping the battery topped up, it should not need to do bulk charging.
An alternative is if your 230V is always on is a small 5A Victron IP65 ac charger.
I do not think a battery combiner is what you need here as the two batteries will have differentcharge requirements. .
Otherwise you will need to look elsewhere for a small DC to DC charger.
Hello and thank you for that input. I will have a look into this device. Does it work LFP to LFP? 230V is not always on, the loss at tne inverter is just to huge to do that if I do not need 230V. That wpuld only be required
I am in Australia, but you might be able to find something similar. I use a power pack like this on my boat for the 12V fridge. It charges with USB-C or a barrel jack that takes 12-24V. I set up a VSR that sends 12V from the AUX battery when the voltage is high enough. The charger is only 45W max, so the cable is very small. Sometimes I forget to turn the fridge off, and come back to a very low AUX battery this solved my problem. Has an anderson out 25A.
thanks for that tip. It is certainly an idea for emergency use. As for permanent solution it seems to be not cheaper than the voctron solution. And not yet another vendor to administer. But perhaps just having this pack ready at hand and in case of just plug it in os a feasible idea!
The Orion 12-12/18 isolated will work LFP to LFP. If you choose the engine shutdown detection at something like 13.0V it can keep charging the radio battery even if the house battery is not on charge, but still not take the house battery too low in SOC.
I visited the 4x4 shop to purchase a 50AH battery, a battery box, and a 25A dual battery kit. However, I ended up walking out with one of these instead. I found myself looking at all the cables, connections, fuses, and even an extra DC-DC charger.