hi. anyone with a straight brain to help please. ive fitted a crabtree split load c.u. On one side i have smoke alarms 1 lighting circuit and 2 ring sockets. protected by a 80amp rccb. these circuits are working and ok. on the other side 3 lighting circuits and 2 ring sockets with the other 80amp rccb. 4 of the circuits are ok. but when i connect the second ring circuit and plug anything in it trips the rccb but not the mcb. it doesnt seem to be the ring circuit itself. I disconnected it at the c.u. and put a single remote socket into the mcb and it still trips when i plug anything into it. anyone any ideas please as ive run out of cash for a pro troubleshooter. thanks