I have a 3KW system with 10 24V 200w solar panels, each 2 in parallel, so total is 2000W.
I use a victron 150/35 and 4 200Ah batteries in series.
I would like to have more autonomy so I decided to add 4 more 200Ah batteires in parallel.
I am wondering if my 150/35 can charge all 8 batteries?
Is there any order in disconnecting and reconnecting the whole system?
Thank you for your help.
This really depends on the depth of discharge you take them to. At 24v 35A you can charge at max 840W per hour given good sun and the right temperatures. So while you have more solar installed you ar enot able to use it effectively. You need a higher amp output charger to keep make full use of the array and charge up.
Beware ! Right now you can charge at 800W per hour, and you are talking of a 2kWp installation, you will have to change your mppt and ALSO the cabling providing the charge to the batteries, also the breaker, etc.
Better provide with more details of your setup to avoid unexpected issues !
Michel
If I understand correctly, you are running a 48v system with 2 parallel groups of 5 solar panels in series.
If this is correct, be careful of your Voc as ‘24v’ panels can quite often exceed 30 volts each which is beyond the 150v max of your controller.
Adding more batteries to increase your autonomy and reduce your DoD should be ok in this case so long as your current system was able to fully charge regularly.
A 35 amp controller is ideal for 300-400Ah of batteries as most batteries (lead acid) prefer a charge rate of around 10%.
As others have noted, ensure your cables and fusing are adequate.
Please let us know your system voltage and check the Voc of your panels to ensure you don’t damage your controller.
Thanks a lot all for your answers.Actually, to be more precise to Vance, I have 2 panels in parallel times 5. Each panel's VOC is 43.2V and short circuit current 6.5A.
By mid day (we have good sun these days here in Morocco) my inverter says that I have a load of 5% and my batteries are 100%.
Batteries are new. I replaced those you can see in picture by 4 brand new ones. First day, they lasted one full night. One month after, they last only until 1:00 am. I got other extra 4 batteries yesterday but I didn't yet connected them until you guys tell me what's wrong. because something is clearly wrong since my batteries autonomy is reducing quite rapidly or they don't fully charged even if my inverter says so.
I also suspected my panels. The original 6 are placed on a rotative arm that I turn manually during the day to follow the sun. The 4 others are on the ground facing east rather than south. that's something I will correct today by turning them full south. Yes I was lazy.
The cabling used from panels to PV combiner box and from PV to MPPT is 4mm, doubled from PV to MPPT.
From MPPT to battery negative is 4 mm2 doubled, and for MPPT positive to battery + is I beleive 16mm2, same as cable between batteries and batteries and inverter.
Eager to read your comments. If you need any other info, please let me know.
Thanks 
Hi @RANY
Where is your battery-state information actually coming from?
You mention an inverter that you quote '%' readings from, but how could that know more than just Volts?
There's no real reason why 2x strings of those batteries wouldn't work perfectly, but if you're using bad data to assess them then you'll always end up disappointed.
Please tell us more.. Victron put a great deal of effort into providing good data, but if you're looking at something else to get it then we can't help much.
At least Volts, and if you're looking at a battery-state % based on V, then you should stop doing that.
