Leisure battery issues??

[Two on Tour]

I know this is an old thread, but I note that "Two on Tour" mentioned a circuit diagram for a BCA PDU.
Apologies for being a bit of an imposter (for now), because although our unusual caravan (made by the Fifth Wheel Company in N Wales) is apparently type approved as a strange hybrid, neither caravan or MH, it is definitely a caravan - despite costing as much as many MHs!
We have just switched to a 280AH Fogstar LiFePO4 battery.
For once I thought I'd take the easy, simple sensible route and just drop in an Apuljack charger/PSU with a "Lithium profile" as a straight swap for the BCA unit. This cost me £260 (by the time you factor in VAT and postage) a few weeks ago.
It turns out that "Lithium profile" is a fixed output of 14.6V.
I will probably sell on the Apuljack unit as "used" as I also happen to have a Fogstar charger to go with the Fogstar battery.
The original BCA PSU will supply 12V to the PDU when on EHU.
I know it's not as simple as disconnecting the battery charging output of the BCA unit and a changeover relay looks like it will be needed.
BCA have been reasonably helpful, but a circuit diagram would be incredibly useful as they are understandably coy about advising on any modifications to their products/looms.
I realise that the caravan and MH PDUs aren't the same, but much of the basic architecture should be similar.
Thanks

Welcome onboard, you will find the schematic diagram for the BCA PSU unit on the thread linked below.

Electrical diagram for Compass Kensington Avant Garde 194 ?

Morning all, I recently bought my first Motorhome (Compass Kensington 194) on a Peugeot Boxer chassis. I would like to improve its off-grid capability by increasing the solar and leisure battery capacity and perhaps changing the leisure battery to Lithium but before I start planning my upgrades...

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