Some advice on my Solar please! :)

[Indigo&Olive]

Hi all, I hope you are all safe during these strange times.

Basically I have 4 x 355watt panels that I am installing on my bluebird in the UK. Cable length will be a maximum of about 3-4metres.

My thoughts are to use a 4 to 1 MC4 connector cable (4mm2 to 10mm2) and then fuse a 10mm2 cable that will run to my 24v MPPT through a solar gland in roof.. Any reasons why i should or should not do this? How would you ground the panels this way?

Im wondering though whether a combiner box would be better? This way i could also earth all the wires to a block then down to the vehicle chassis/neg bus bar.

The bus is not really going to be driven and more of a off-grid tiny home.

Panel stats-
Watts 355
Maximum Power Voltage - Vmpp(V)35.7
Maximum Power Current - Impp(A)9.95
Open Circuit Voltage - Voc(V)41.4
Short Circuit Current - Isc (A)10.65
Panel Efficiency (%)20.7
Cell Type Mono

Any advice would be well appreciated!

[PNW_Steve]

If you want to parallel more. Than two strings you will need a combiner with overcurrent protection.

I am partial to the Midnite combiner and DC breakers.

[Doktari]

I agree, combiner boxes are worth the extra expense, and make working on and testing the system more convenient. The Midnite combiner boxes are outdoor rated boxes. Outback makes them now also. Ive only used the Midnite boxes as they cost less. Ive seen the high voltage DC breakers for as low as $$13.50.