A method of establishing current limits for each of a plurality of device couplers mounted on a trunk of an electrical circuit at distributed physical positions, in which each of said device couplers is capable of servicing one or more spurs connected thereto, and in which said trunk has a total trunk current and a known resistive component, comprising the steps of: a) establishing physical characteristics of the electrical circuit including i) an order in which said device couplers are mounted on said trunk along its length; ii) a load current each device coupler requires to service the one or more spurs connected thereto; and, iii) a voltage drop of each of said sections of trunk caused by the resistive component thereof, which is proportional to a physical length thereof and the combined load currents of each device coupler serviced by that section of trunk; b) calculating a current limit for each device coupler, which current limit is greater than said load current, according to a predetermined tolerance rationale; c) calculating an intermediate trunk current available to each device coupler by deducting from said total trunk current the current limits of each device coupler preceding that device coupler in said order, as well as a consequential reduction in current caused by said voltage drop of each of said sections of trunk preceding that device coupler; and, d) adjusting said current limits so none exceeds the intermediate trunk current available to the corresponding device coupler.