Patent ID: 8718964

Claim:
A system for calibrating an electrical current measuring device which measures electrical currents passing through a plurality of conductors, the system comprising: a calibration device configured to selectively draw electrical current from more than one conductor in said plurality of conductors, said calibration device adjusting said electrical current it draws from said more than one conductor in said plurality of conductors in a controlled manner, said calibration device also measuring changes in said electrical current it draws from said more than one conductor said plurality of conductors, said device being electrically coupled to said plurality of conductors downstream of a plurality of electromagnetic effect sensors of said electrical current measuring device, each of said plurality of electromagnetic sensors being configured to measure a combined electromagnetic effect of said currents passing through all of said plurality of conductors; a processing unit for determining a relationship between an output of each of said plurality of electromagnetic effect sensors and currents in said plurality of conductors, said relationship being calculated based on said changes in said electrical current drawn by said calibration device and said output of each of said plurality of electromagnetic effect sensors as said combined electromagnetic effects of said currents are measured by said plurality of electromagnetic effect sensors; and wherein said current measuring device communicates its measurements to said processing unit; each of said plurality of conductors is parallel to one another; and said plurality of conductors are bundled together.