Patent ID: 6748344
Filing Date: 2004-06-08
Classification: G01R

Abstract:
An apparatus for measuring and displaying an electrical parameter of an electrical system, said electrical parameter having a nominal value, said apparatus comprising:a non-volatile memory storing a scaling factor; a divider providing a first analog voltage from said electrical parameter of said electrical system, said first analog voltage having a first magnitude; an analog to digital converter circuit converting said first analog voltage to a first digital value; a processor comprising: a first routine calculating said scaling factor by subtracting a second digital value from a third digital value, said third digital value representing said nominal value, said second digital value being converted by said analog to digital converter circuit from a second analog voltage from said divider, said second analog voltage having a second magnitude, said divider receiving a third analog voltage having a third magnitude, which represents said nominal value, said second magnitude being less than said third magnitude, said second digital value being less than said third digital value, an input circuit for said first routine, and a second routine retrieving said scaling factor from said non-volatile memory and adding said scaling factor to said first digital value to provide a sum; and a display displaying said sum.