ABSTRACT
This chapter covers some important terms/topics such as design current, diversity, basic circuit design, nominal rating of protective devices, rating factors, cable selection and voltage drop, shock and thermal constraints, and selection of circuit protective conductor (cpc) using tabulated values or the adiabatic equation. It explains the sequence of steps in a simple design procedure, calculation of single phase design currents, and selection of suitable protective devices. It explores the importance and application of rating factors, and selection of appropriate cable sizes for current-carrying capacity and voltage drop. Then, it focuses on the determination of shock risk and cable thermal constraints, and carries out simple design calculations. In calculating the maximum current, appliances and socket outlets should be considered in order of their current ratings. Having ascertained all the necessary details, people can decide on an installation method, the type of cable and how people will protect against electric shock and over currents, with calculation part of the design procedure.
