Method of optimizing automotive electrical wiring

A computer-aided engineering apparatus for selecting wiring components for a circuit including at least one predetermined load in an automotive electrical system using a data processing device, the computer-aided engineering apparatus programmed to perform the steps of:

• a user identifying a fuse type for protecting the circuit, wherein the fuse type is identified by a current rating and a case size;
• obtaining from a lookup table in the data processing device a target current needed to achieve a desired fuse blow time for the identified fuse type;
• obtaining from a lookup table in the data processing device a minimum wire size for supporting steady state operation of the circuit in response to the identified fuse type, wherein the minimum wire size supporting steady state operation is determined in response to a current equal to about 80% of the rated current of the identified fuse type;
• the user identifying one or more wire segments to be included in the circuit, including specifying a respective wire length for each of the one or more wire segments;
• the data processing device calculating an aggregate circuit resistance including each identified wire segment, wherein when a wire segment is first identified it is assigned the minimum wire size and its resistance is determined based on its respective length;
• the data processing device calculating a provisional short circuit current in response to the aggregate circuit resistance;
• the data processing device comparing the provisional short circuit current to the target current;
• and
• the data processing device prompting the user to select an increased wire size for at least one wire segment if the provisional short circuit current is less than the target current;
• and
• the data processing device indicating an optimized circuit if the provisional short circuit current is greater than the target current.