RCD problem

Hi, my names Mick. I live off grid in 7 acres of woodland near Chepstow. I've been here 3 years now and can't imagine life anywhere else. 

I have a spring for water and 640w of solar supplying 3x100w deep cell batteries. 

I also have a 3kw diesel generator to run my washing machine and at this time of year to up my batteries. The genny has been performing perfectly well for 16 months but last week the 16amp RCD kept flipping. 

I checked the extension from the gen and the wiring to the washer(&water pump). All good. After resetting for the 10th time, the RCD stopped working. I have replaced it with a 25amp unit and it was still the same,even with nothing plugged into the gen.

The original RCD unit had the earth and negative wired into the same side of the RCD which I have copied onto the replacement. 

Today I tried it one last time and it is working perfectly. I know these intermittent problems are the worst but winter is the when the batteries, therefore my,for want of a better word 'house's, needs it the most.

Thank you for taking the time to read this, and for any advice you might have to offer.

Mick

Where is the generator located? Damp? 
also they are not designed for continuous running? 

640W of solar does not sound much.

If you want inspiration for off grid living, take a look at https://lifeattheendoftheroad.wordpress.com/about/

You really want a fixed generator properly set up in a generator house, not a portable thing.

Thanks for responding. 

The generator is from army surplus. It's a Lambordini. 

It is outside but covered when not in use. There's been zero issues with it until now.

I know 640w solar not a lot but I only have 3x 12v DC spotlights and a TV & sat receiver. + phone charging. The washer runs once a week most months so I saw no need for fixed power source. 

Finances dictated my set up, as well as distance from the nearest lane access (1 mile across 3 streams )

Just sounds like you have damp in the electrics somewhere, or mouse damage to a cable? 

Ok,I'll build housing around it. It seems that's the best I can do.

Its worked perfectly since I first posted so maybe it just had flu

Thanks to all for taking the time to respond. Mick