Firefly system Magnum to Victron

[Mofford]

I have a 2019 Monaco Signature 44M. I have been having a few issues with my Magnum MS2812 inverter/charger. The coach came with the Lithium battery package (8 Dragonfly LifePO4 100ah). It seems like the inverter/charger was not setup for this at the factory and therefore will not fully charge the batteries. I have been able to setup a custom battery profile in the VT Mira screen for the lithium but it keeps reverting back to the factory profile for Lead Acid.

I am looking to switch to a Victron inverter/charger, Cerbo GX, GX Touch, 8 SOK 280Ah Batteries and more solar panels.

From what I have heard from Firefly is that I can't change out the Magnum inverter since that has the control over the inverter and BMS, but through my research I have seen some people have switched but then possibly lose control of the inverter through the VT screen. Which I am fine with as I will do a Cerbo with a GX screen and add a Victron BMS.

If I make the switch will I lose control of anything else or have any other issues? My hope is that someone has made this switch and could shed some light. Any help is appreciated.

[B-Man]

If you install the Victron equipment and SOK batteries you listed, it should operate just fine. The Cerbo, coupled with the GX screen, will give you a GUI to interact with the system.

I am unsure why you want a Victron BMS as the SOK batteries already have a BMS?

[B-Man]

Originally Posted by Obtain High

BMS Integration:

The Magnum inverter/charger communicates with the factory-installed lithium battery BMS.

By switching to Victron and adding the Victron Smart Lithium BMS, you’ll have better control and monitoring of your new battery bank, but this will require decoupling the Firefly system from the BMS.

Please explain how a Victron BMS works with non-Victron batteries. Their BMS product pages all specifically state that each of their BMS units is designed to work with Victron batteries.

Thanks.

[Turbojack]

There is a thread in the Entregra section that has done this and has had good results. Just go to the search window and find the thread.

[Mofford]

The SOK internal BMS is fine, but I’d like to integrate everything into the Cerbo so I can monitor and manage it remotely when I’m not with the coach.

The main challenge lies with the Firefly system. According to Firefly, unless my VT system has an override switch to disable the BMS (which it doesn't), I won’t be able to use a Victron inverter/charger. It seems that Firefly communicates directly with the inverter/charger to manage when charging occurs, and this may also affect the HVAC and other functionalities.

I could be misunderstanding some aspects since I’m not deeply experienced with RV electrical systems. While I’ve successfully installed similar systems on my other coaches and trailers, the combination of Firefly and its limitations has me at a bit of an impasse. Any guidance or clarification would be greatly appreciated!