Forum Discussion
Almot
Mar 08, 2016Explorer III
Run Morningstar string calculator for 2*255W in series to make sure the maximum Voc is below 150V at low temps like 20F for TS MPPT 45.
I haven't heard of big panels breaking on trailers - this has been discussed too, you can reinforce the panel frame and/or add more mounting brackets.
510W will harvest more energy than 400w, no matter what controller or series/parallel.
With Tyco connectors you need to buy Tyco extension cable (they exist), and Tyco Y-connectors if wiring parallel (don't know if these exist). Maybe shop around and find 2*255W with MC4, this type is prevalent, plenty of cables and connectors. 260W MC4, $234
Edit - PS: forget about string calculator for TS MPPT 45. 2*255W or 2*260 will never exceed 150V.
I haven't heard of big panels breaking on trailers - this has been discussed too, you can reinforce the panel frame and/or add more mounting brackets.
510W will harvest more energy than 400w, no matter what controller or series/parallel.
With Tyco connectors you need to buy Tyco extension cable (they exist), and Tyco Y-connectors if wiring parallel (don't know if these exist). Maybe shop around and find 2*255W with MC4, this type is prevalent, plenty of cables and connectors. 260W MC4, $234
Edit - PS: forget about string calculator for TS MPPT 45. 2*255W or 2*260 will never exceed 150V.
About Technical Issues
Having RV issues? Connect with others who have been in your shoes.24,344 PostsLatest Activity: Dec 26, 2025