Got a job on the go which is TT (stables), they have several sub CU's.
Now, I feel that I have 3 choices as to the earthing-
1. put a rod in at the incommer only!
2. put a rod in at every CU with all being linked by a common earth
3. put a rod in at every CU (leaving incomming earths to CUs disconnected
Any of these options is better that they had, as someone had connected to an earth block on the side of the cut out which was not connected! I had to knock in some 22mm pipe that I had in the van as a temporary measure (got 5.57ohms which suprised me!)
P.S. there is a 100mA 'S' type RCD at the incommer and all socket circuits will have 30mA RCD protection
Now, I feel that I have 3 choices as to the earthing-
1. put a rod in at the incommer only!
2. put a rod in at every CU with all being linked by a common earth
3. put a rod in at every CU (leaving incomming earths to CUs disconnected
Any of these options is better that they had, as someone had connected to an earth block on the side of the cut out which was not connected! I had to knock in some 22mm pipe that I had in the van as a temporary measure (got 5.57ohms which suprised me!)
P.S. there is a 100mA 'S' type RCD at the incommer and all socket circuits will have 30mA RCD protection