You have calculated the volt drop for the length of the sub main only, there is no allowance for sub circuits connected to this sub main at the new end, lighting circuits will be the main concern, for a sub main I always aim for about 1-2% VD max at the sub main end so you still have allowance for your sub circuits on top of that
At that distance, carrying that sort of current, it will be a larger cable maybe looking at a parallel supply, Zs will also be an issue!
At that distance, carrying that sort of current, it will be a larger cable maybe looking at a parallel supply, Zs will also be an issue!
