Hi Bendik,
The link I gave you was not so much as to how to choose the controller but more at this stage to look at the voltages for particular panels and how temperature affects them and therefore current output, by using the spreadsheet in this page.
http://www.victronenergy.com/blog/2014/03/28/matching-victron-energy-solar-modules-to-the-new-mppt-charge-regulators/
For instance I have a 24V bank of batteries and use two 12V, 30 Watt Monocrystalline panels in series so that is 36 cells per panel x 2 and so I have 72 cells.
This voltage business is important as for the controller (MPPT better than PWM) to start charging , the panel voltage needs to be plus 5V over the actual battery voltage and that voltage is affected quite considerably by ambient temperature and how that affects panel temperature. Cooler panels are better.
I attach the sheet for my boat and my controller so you can see.
In Summer at my 55 degrees latitude in Scotland with the two flat panels on the stern I get in the worst case 1 x panel rating output over the day i.e 60 Wh, best is 6 times panel rating which is 300 Wh. No room for more panels but on average in Summer I get 180 Wh i.e. 3 times panel rating. Now if I divide by 24 hours and pull 1 amp every hour from my 24V string for 24 hours you can see I would consume 24 x 24 x 1 =576Wh BUT as I only sail say for 8 hrs then divide 576/3 and that gives 192 Wh consumed which is close to my average 180Wh harvest and as my instruments take around 1 amp at 24 V nominal, then my small 60 Watt solar array caters for my boat instrument loads, and of course when not being used the panels help recharge the batteries.
Hope that helps. Do look at the voltages. The sheet helps you decide if you have enough voltage for your batteries for a variety of conditions. Note in the example I have sent you how temperature affects output current due to voltage changes and min PV and max PV voltages due to temperature changes.
Note that in the sheet under the modules tab you can enter the data for the panels you choose in the 3 custom fields.
Attached a pic of my panels and generator. The panels are placed there to limit shading and help cooling.
I keep a public timeline of my boat conversion here Elektra Yachts
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