Tipical , Im trying to find out the very same.I do know its more than 2 meters though.
I`ve ran 15 meter tails to the new meters position which was what the Electricity Board suggested , so i know thats ok , but i need to know is 25m still ok,and is it ok to use 10mm twin & earth instead of tails.(coz i can`t see what the difference is in theory)