question

@Luca Barbierato, sorry it's taken so long to get an answer to you!

I'm curious about why you're choosing to use an ArgoFET here; in the layout you show, it seems you could just as easily forgo the ArgoFET and simply connect your two BS batteries in parallel, and connect your two charge sources to the batteries as would normally be the case (ie, POS connections to one battery and NEG connections to the other, with POS and NEG jumpers between the two batteries). I must assume that you have some other reason, not immediately apparent in the diagram, for keeping the two batteries separated?

That being said: this will technically work. It's not an approved connection method for the ArgoFET, but I've tested a similar layout on my test bench and it does work quite well. The caveat, of course, (and this goes for any time you have multiple charge sources connected to a battery) is that since both the MPPT and the Orion-Tr Smart look at battery voltage to determine their charge state, whichever one is running first will be raising the battery voltage, which means the second one to start running will be in a different charging phase - ie, the second charger to start running will go into absorption and float sooner than the first one. This is not a real problem, however, as the end result either way is that your batteries are getting charged, it's just that people often think that two separate charging sources need to be in the same charging stage, and you should be advised that this will not be the case.

Otherwise, I'd say go for it... I don't see any reason why this won't work as you intend.