question

One thing to keep in mind is the relationship between your battery voltage and panel voltage. From what I understand, you want to feed the 100/30 with as much voltage as you can without exceeding the 100V max of the unit in order for it to work best.

Therefore, you should consider wiring your 100W panels in series (depending on their Vmax specs) to maximize voltage input to the 100/30.

You need more V coming in from the panels than the voltage of the bank you are charging. I’ve been reading on here that most of the MPPT’s wont turn on unless they are getting 5V more than your bank and will stay on until it falls below 1V. The more the better without exceeding because the panels don’t put out max voltage unless conditions are perfect.

This is the advantage of MPPT chargers as I understand, in that you can “over volt” them so that extra voltage not being used to maintain the batteries can be used instead to power a load while still maintaining the bank.

Others can correct me if I’m wrong, but that is what I’ve learned and what is important to keep in mind and understand when configuring your MPPT system. You have a 100V/30A capable unit and enough solar to feed it, so why not take advantage and use the components as efficiently possible.

Of course that’s all based on a scenario where you are actually using the MPPT units to charge batteries which you didn’t mention any details about.

The other caveat is shading. If these 4 panels aren’t going to see similar sun conditions and are say mounted on port and starboard, then wiring in series can obviously work against you depending on the scenario and their specs.