Shed’s roughly 30m away from CU. I’ve got 4mm SWA already buried and at both ends, what size breakers would be ideal or could I fit it into the mains switch then into a rcd in the shed?
32A breaker in your house consumer unit. Garage consumer unit with 40A mains breaker, 32A breaker for the socket ring, 6A for the lights.
How do you know 4mm is big enough? What is being powered? What is the expected load? What do you mean by