For a marine application I am looking into a system with both 12V and 48V battery banks. The 12V rail (Victron NG battery + Lynx NG) would be used to power all the usual stuff like lights, navionics, fridges etc. whereas 48V would be used for bulk storage (Pylontech battery modules connected via CAN) and to power inverters. PV and other sources would all feed into the 48V bank and the 12V bank would be charged using an Orion-Tr DC/DC carger.
In this setup the Cerbo would need to deal with both the charging of the 48V batteries DVCC style as well as the DC/DC-conversion of the 12V bank. I realize that there is no Orion-XS 12/48 yet, so the only way to control the Orion is via the ATC output of the Lynx. Therefore the Cerbo would only actually need to manage the 48V side DVCC style. But it would still be required to monitor the SOC of the 12V bank. Does the Cerbo bet confused by seeing two separate battery banks?
Hello Jörg … Welcome in the Forum
A very brief NO… Only one system voltage and battery bank are managed.
You can, of course, use shunts and other components to bring values from other voltage systems into your system… BUT, as you already wrote, this will confuses the Cerbo…
The graphical displays will not function correctly.
A solution via NodeRed or possibly SiganlK for the marine sector would be one option.
In short… you get the data… but you have to think of something for the graphical display.
Use the Cerbo to control the 48V system normally.
Then use DC / DC converters to power the other stuff. Only maintain a 12V battery for emergency use with the radio.
Depending on the size of the yacht, run either 24V for lighting and navigation (large) or 12v (small).
Then the 12v battery can be monitored by a smart shunt as an aux battery, keep this independent from the engine starting battery. Have some thought also to emergency lighting.
Thank you @MikeD and @Netrange for the warm welcome and your expertise.
@MikeD your suggestion is to not use a 12V battery bank at all? The yacht has an existing 12V system and AGMs for the house bank. Most of the consumers on the house bank could probably be powered directly via DC/DC, but I am now so sure about the power winches (briefly high power) and the fridges (high inrush current). Also, as you mentioned, for certain stuff I need sufficient backup capacity (navionics, radio, bilge pumps, emergency lighting), Thus the idea to use a separate 12V battery bank to buffer the 12V consumers.
I think I can get away with either a set of self-managing batteries emulating Pb chemistry (Liontron etc.) and an Orion charger or Victron NG batteries + Lynx NG + Orion using ATC wiring. I understand that the Cerbo might get confused if it sees two disjoint battery banks. Would it still be possible to use the Cerbo’s IO infrastructure (CAN) to acquire the data but not use it for management and just forward it to NodeRed or SignalK?
Why do you want to operate a 48V system… and not go for 24V, for example… there are already projects like that here. Do you have large loads that you absolutely want and need to have on the 48V side?
The problem will be charging the 48V bank. PV modules will only have the necessary start-up voltage for the MPPT in series connection… or do you have drive machines that are supposed to take over the charging? Or perhaps a shore connection… via a Multiplus, etc.?
Ok, if you have 12V power consumers like windlass and power sheet winches, then you will need a good 12V bank of battery, unless you upgrade those motors to 24V. On a Yacht I would not go higher than 24V UNLESS you either need >5kW from the inverter, or are using electric drives.
Following. I do have a 48V bank with a 10KVA Multiplus 48/220 for all AC loads and a 12Volts bank for all other loads including fridges, winches and winlass. The Cerbo only shows the 48V system in the graphic display and I can see 12V voltages and state of charge from a smartshunt with a widget in VRM
