Connecting different spec solar panels.

Londonboii

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Sorry if this has come up before but when looking through various posts online I cant really find a clear answer to what is the best way forward. I believe I understand the issues but I dont know the best way forward.

I currently have 2x 160w solar panels connected to a ring rsdc30 controller. Panels are connected in parralel on the roof then 2 cables go to the controller. All wire is 4mm. I want to add 2 x 185W panels to the roof and I am not sure what is the best way to add these in to my setup. I have bought a victron mppt controller 100/50 as the ring controller wouldnt take the wattage according to the spec sheet.

1= If I connect them in parallel to the existing 2 I believe I would need to upgrade to thicker wires and would lose some of the additional power from the 185W panels? It would just be as if I had 4 of the 160w panels? Higher total amperage may mean I need to increase the diameter of the wire?

2= Would it then be best to wire them all in series? I could keep the wiring 4mm but the amperage would be lower, which will slow down how fast the batteries charge?

3= should I leave the existing panels as they are and then wire the 2 new in series also. Then connect the 2 pairs of panels in parallel?

4= I could leave the ring setup as it is and simply add the 2 new panels with the victron in to the batteries also?

All these options for setting this up is confusing and have negatives so its difficult to know which would be best.

185w specs:
Max Power Voltage. 18V
Max Power Current. 10.3A
Open Circuit Voltage. 21.6V
Short Circuit Current. 11.2A

160w specs:
Maximum power voltage: 18.8V
Maximum power current: 8.48A
Open circuit voltage: 22.9V
Short circuit current: 9.02A

Sorry for the lengthy post.
 
Options:
Use two controllers - Ring for existing, Victron for new
Pro - no compromise by mixing
Cons - have to run additional wiring panels through roof (more holes) to controller and then to battery; How well will Ring and Victron play together?

Use Victron controller for all
Connect all in series - Loose around 65W. Existing cabling is fine (max current is 8.48A); Voc is fairly close to limit of controller (89V)

Connect all in parallel - Loose around 14W. Existing cable is borderline (max current is upto 37A); Voc is not an issue (21.6V)

However, my suggestion would be connect a single 185W and a single 160W in parallel; do the same with the other 185W and 160W panel; then connect the two pairs in Series (so combination of the two, but in the right order).
Loose 7W per pair (so 14W in total); Existing cabling is ok (max current is 18.78A); VoC is not an issue (43.2V)
Maximise benefit of Victron controller (very likely outperform Ring by more than the 14W of losses by using Victron for all); Don't have to mess with cabling*

*Whichever way you cable (Parallel, Series, or Parallel/Series combination), remember the cable from Controller to Battery should be sized to support the current of the combined panel array (potential close to 60A at 12V)
 
You will need a second pair remember - from Victron to Battery (I presume you are keeping the Ring for the B2B side?)
If you are fitting the Victron MPPT next to the Ring B2B (probably easiest as that as where the Solar Cables are terminated currently), then you could potentiall connect the Victron Battery Out +ve and -ve to the Battery Cables into the Ring and save running another pair all the way to the battery - although pairing up cables on those kind of clamp terminals can be pretty awkward :(
 

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