Patent ID: 6188552
Filing Date: 2001-02-13
Classification: E21B,H02H

Abstract:
An electrical system of the kind which operates normally in the ungrounded state but which occasionally is subject to a conductor thereof being grounded, wherein an undesirable voltage is generated between a first portion of said electrical system and ground, comprising:grounding impedance means interconnectable to a second portion of said electrical system for reducing said undesirable voltage by connecting said second portion to ground;control system means interconnected with said grounding impedance means and said electrical system for sensing said undesirable voltage and connecting said grounding impedance means to said second portion of said electrical system for reducing said undesirable voltage;said control system means, comprising:gated conducted means interconnected with said impedance means for interconnecting said second portion of said electrical system means to ground through said impedance means for reducing said undesirable voltage; andcontrol means interconnected with said gated conduction means for causing said gated conduction means to interconnect said second portion of said electrical system means to ground in response to the presence of said undesirable voltage.