Hello everyone,
I have a question about feasibility of a design idea for a sailing vessel.
The setup is
. three Victron MPPT charger (connected to Cerbo)
. one Cerbo GX (connected to NMEA2K)
. LYNX Smart BMS and LFP batteries (connected to Cerbo)
They are interconmected so that the LFP get charged by the Solar panels.
Now, I have a second circuit consisting of
. Motor alternator (very old type)
. 4 AGM batteries in parallel. Two for the starter and two for the bowthruster and windlass.
These two circuits are not connected.
Since I do not want to use the motor much I have to find a way to keep the AGM charged.
So, the idea is to use an Orion DCDC charger between LFP and AGM circuit and remote control the charger with the Cerbo by the parameter
Switch the Orion on when
. the voltage of the AGM circuit is less than i.e. 12.5 V AND
. the LFP SOC is >80% AND
. the MPPT are charging
If this is possible I should be able to charge the AGM without risking depletion of the LFP side (unlikely actually). But I struggle to see how I can input the AGM side voltage measure into the system. Also, all documentation always use the Orions to charge the LFP side from the AGM side and not reverse as I want to do it.
Any ideas on that? Is it possible with a Smart Orion or would it need to be a Orion XS?
I am quite familiar with node red and can add hardware to the system (i.e. a HAT for a Raspberry Pi to measure something) and have that outputted to NMEA.
Thanks
Mathias
You could use the relays on the cerbo. If you connect a battery protect to the AGM bank and then use the alarm relay to close at 12.5V send a signal to the cerbo to check the logic SOC> 80% and MPPT power > 0 using node-red then switch the relay until the MPPT stops or SOC drops and maybe set a time limit based on how long it takes to charge from 12.5V to the safe level you want in the AGM.
Thanks for the answer. The battery protect is required to measure the voltage of the AGM side, correct?
Adding that is a bit problematic since the 4 batteries are divided into two banks about 10m apart…
And the bowthruster and the statrer motor are really powerful…
Ok, the Orion XS is indeed connectable and manageable with the Cerbo. My question is here, can the Cerbo read the battery voltage of the output side (in my case the AGM side?)
The battery protect is there to sense the voltage and alarm when it’s low. Connect to any bank if they are in parallel they should be the same. You don’t need to use it as a battery protect just leave the load side disconnected. You could use another shunt for starter battery and set it up that way to measure voltage as well by they are more expensive. There are many different ways to do this.
Thank you both of you. That helps me a lot. I think the solution with the XS is the better one since it is one device less to work with. I now just habe to figure out how to connect 3 MPPT, one BMS, one GPS Usb stick and the Orion onto the Cerbo…
Cheers
Mathias
If the MPPT’s are ve.can units, then connect those via the can bus and then use the vedirect ports for the BMV and Orion XS.
Otherwise vedirect to usb cables and you will need a USB hub, unless you have a later model cerbo
Thanks,
I am aware of that. I do not have the 3 USB version so I have to install a Hub and move one MPPT to USB. All MPPT are 100/30 smart, Ve.direct.
It is more a problem of routing cables and placing elements…
Mathias
