I remembered my password again, sorry to be away for so long.
I have been reading on and off topics but was unable to reply.
I am still alive and actively involved in electrical work on the Auckland Network.
11 kV take off circuits are usually fused. In case of a single transformator, dedicated fuses are used, often 50 % over the nominal rating. e.g a 100 kVA TX draws 5.5 Amps at 11 kV per phase. These TX's are fused with 8 or 10 Amp ddo's or HRC fuses in an underground network.
A different situation occurs in a street fed from two directions with an open point in the middle. There could be 2 or 3 transformers either side of the open point. Fuses are heavily overrated in this case to allow all the transformers to be fed from one end. I have seen 100 kVA TX's fused with 60 Amp HRC fuses, which means no protection for the TX.
