Here's a bit more info (and some more questions!);
I'm actually running two separate cables, one to an outbuilding about
20 feet from the home CU (cable runs above ground, along outside of
house - this cable was already installed - 6mm T&E, I think). The
other is a 10mm 3-core SWA to a workshop, which I just laid, the cable
run is about 100-120 ft from the home CU, and runs underground for the
majority of the run.
I've obtained some earth rods for both installations.
I'm still not 100% sure what to do with the earth wire on the cables.
Do I earth them at the house end, and just ignore them at the w/s or
outbuilding end, and just hook-up the workshop CU earth to the earth
Currently, in a special (and very expensive!) junction box, I've
joined the earth core wire with the outer cable shielding. It's not
Can I not test the earth impedance with a multimeter?