Partial shade on Jayco solar panels

Thanks Peter,

What I should have added is we run our Dometic 3 way fridge on 12v while mobile drawing 10 amps approx.
If there was a thin shadow from the boat rack bar it would affect both panels as they are side by side and yes 12V wired parallel.
There are shadow variables like change of direction but I suppose if at start of journey the batteries were at 100 per cent then in say 10 hours day travel in clear sunshine I'm thinking the battery voltage should still be acceptable at days end but depending on charge loss from shade.

Mike

that's ok Mike,

so the fridge drawing 10 amps while travelling....hmmm
Say you're on the road for 10 hours, then your panels (unshaded) will give you 8.7 amps during an 8 sun hours period.
So your batteries will see a slight reduction in charge during the day.
I guess at the end of the day you recharge them by means of a mains powered charger, or a gennie?

It's hard to predict the amount of charging current loss from the partial shading, but it could be significant.

In case you're using a mains powered charger at the end of the day, it doesn't really matter because it'll recharge the batteries overnight, no matter what.
Different story if you had a gennie, because you want to keep run times down...

What about getting some charge from the alternator while travelling?

Best regards, Peter

If the charge loss is this great then the racks will be coming off as they are not used and are there because they came with the camper when purchased.
Obviously I should do the test at home with fridge on and simulate boat rack shadow across both panels.

Mike

Mike, good to test but rather than fridge just get yourself an ammeter (2/120w panels might be a bit beyond a multimeter) if your regulator does not show amp flow - easy to do and very informative. Cheers

Mike,
Why not top up the van battery via an anderson plug and the vehicles alternator, then the van batteries will be in good shape.

Peter

Why compromise a good setup? if the racks arent used Id remove them & get the best out of the panels. Cheers Daryl

Hi Mike,

Peter is on the money with the Anderson plug off the car - your alternator will be pushing a lot more amps than your solar panels. Make sure your wiring from the Anderson plug to the fridge is heavy too.

Cheers,

Mark.