power goes off

Unlikely to be a spurious trip on two seperate ocassions, sounds like the fridge to me BICBW

NEVER HAPPENS WHEN WE ARE HERE

OK. Get the farmer to cut the grass when you're there and see what happens. Better still chuck all manner of wet stuff on the plug and socket.

Condensation?

Bill

If you are in any doubt put a plastic bag and duct tape over the connection.

Brian

Presumably all the extrenal plugs and sockets are the 16 A or 32 A round CEE things not an ordinary 13 A plug and socket and that everything has a proper cover on the meter post.

A bit of wet grass splatter shouldn't worry a fully mated CEE plug and socket.

And when you say every thing is switched off is that on their switches/unplugged or all the MCBs in the CU apart from the one feeding circuit the fridge is on.

yip

yip...anyway I took off the cover again and reset the rcd...this time I unplugged the blue plug and sprayed everything in wd40...I can but hope....

Good lord that must be a first, some one using WD40 for what it's supposed to be used for!

Wonder if farmer is is unplugging the lead to move it out of the way when mowing then putting it back in? I wouldn't expect a 30 mA RCD to trip due to cable capacitance on it's own but is stuff in the van is still plugged in all the filter capacitors will still be across N & E.

nah don't think so...and why are the RCDs at the consumer unit not triggered ? ......well I use wd40 for everything so just luck that I was using it for its intended use..and he obviously mowed around the meter box but I notice he hit the plastic box with the washing machine in it and no we use an extension cable for that but it has water feed and drainage,,,,

They are further upstream. Won't see the inrush do to cable capacitance from meter box to CU. Will only see the filter capacitance of devices on their circuit. May be less sensitive (even if the same nominal rating).

so it shouldn't be the fridge or anything in the van then? ....

The only way to answer that is to test everything for earth leakage. If you don't want the expense of a megger, there are 2 cheap options

1. a multimeter sometimes detects failing insulation
2. You can also make a tester using just Rs & a neon.

NT

Wouldn't like to say.It could be leakage anywhere upstream of a given RCD that pushes it over the edge.

I would guess the fridge, just had the same thing happen to my freezer (house), apparently its a fairly regular occurance judging by the amount of chatter online about it.

If the RCD is of the non-latching type, then a power cut or short glitch would require someone to reset it. Look up the make and model for the spec.