PV Array trips RCD's

[Gavin A]

Yes. 4 core swa, with the armour connected to the earth pits at either end.

right, RCD located on a board at the end of the road... I'm plumping for incorrect IP rating, resulting in condensation on cold damp nights that's tripping the RCDs.

and if it turns out I guessed that right, I'll be erm quietly impressed with myself, but it's a bit of a longshot.

 

[BruceB]

As a starter for 10 I would get an electrician to test each of the rcds to make sure that they are tripping at the correct value.

I would also consider making the rcds at the entrance type S (time delayed) rcds so that you have proper discrimination between the house rcds and the road entrance rcds.

It sounds like you might have a couple of TT systems run in parallel which is inviting trouble from faults in one installation causing trips in another.

I hope your electrician and the DNO had a really good reason for bringing in 2 separate single phase supplies and metering it at the roadside. It strikes me you would have been better just bringing in a 3 phase supply to the house and metering it there. At the moment on cold winter days and nights you will be paying for the electricity that is heating the ground between your entrance and the house, which adds up over say 20 years.