thanks again, we used BS standards under the DEWA supervision, Im sorry i misleading you. brief explanation :
the tenant units (i.e retail, Food and Beverage,open cafe etc) inside a mall supplied by the DB three phase neutral panel, ranging from 60 A TPN to 800 A TPN, connected to an Isolator which is connected to MDB. I wish to know where to install the DBs within the tenant space base on the regulation.