I was wondering if someone could tell me whether my thinking is way off the mark/close-ish.
I have (from a previous vehicle) a smartsolar MPPT 75/15 with bluetooth. I have just purchased a vehicle that has a Kings 25a DCDC charger/mppt combo - however, it doesn’t provide trending and value plotting like the Victron.
I was wondering if I could use both? Maybe by connecting the Victron ‘in-line’ before the DC-DC Kings charger?
Probably overkill, and it’s just for the app features really, but I have both so would like to figure how to make it work.
Sure you can use both. The only stipulation is that you don’t want the combined output of the two (or more) charging devices to exceed what the battery bank can accept.
I would wire them in parallel, not series.
Here’s a thread that discusses charging from multiple devices:
Kings website provides only basic specs for their 25A DCDC unit but did indicate that its maximum solar input voltage is 32V. If using more than one PV panel then series connection will exceed the 32 V limit with most of the panels that are popular for vehicle based systems. Your SmartSolar 75/15 will accept a series connection with the benefits of more efficient MPPT operation at the higher input voltage.
Consider also adding a Victron smart shunt to your system; it can give a fairly accurate indication of your battery’s State of charge and can network with your 75/15 to input a more accurate battery voltage to the charge controller