I have dug a little further into the vagaries of the RSCDC30 and can now report the following...
Went out yesterday with leisure batteries reasonably well topped up having not been used for other than minor interior lighting for the past week or more. The weather yesterday meant that the PV was supplying very little.
Did a round trip of some forty miles and on my return home was of the opinion that the leisure batteries were not topped up as they should have been after said trip.
RSCDC30 display was showing a very minor amount of charge from the PV .
Started the engine and watched the display, it remained on PV input.
After some five minutes of engine running I measured the voltages on the RSCDC30 terminals - Alternator source input measured 14.82v - but unit still showing that it was charging from the PV
I then entered configuration mode by pressing the MENU button for 2 seconds. Released the button then did the same again to exit configuration mode.
On exit from config. mode the RSCDC30 immediately began charging the leisure batteries from the alternator source.
Sorry Fari, this is what I was saying in my previous report. It does not exit PV mode automatically even after considerable time of engine run!
I've not had chance to examine the voltage applied to the RSCDC30 alternator input terminals when the unit appears to trip out but knowing the cross section of the cabling and connections between the engine battery and the RSCDC30 I don't suspect a significant volt drop to cause this. I'll do some recording when I have chance.
Rod
PS - Pauly, if you are think that Fari does not follow thread this please will you bring it to his attention.