Methods and apparatus for continuous ground fault self-test

Patent metadata

Field	Value
Publication number	US-9239368-B2
Application number	US-201313748343-A
Country	US
Kind code	B2
Filing date	Jan 23, 2013
Priority date	Nov 2, 2006
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

Methods and apparatus for continuous ground fault self-test are disclosed. An example ground fault detection device includes a sense coil to detect current in a line conductor and a neutral conductor, the sense coil comprising a winding influenced by a current difference between the line conductor and the neutral conductor. The example ground fault detection device also includes a current bypass to facilitate a continuous current imbalance detected by the sense coil, and a ground fault detector circuit to detect at least one of the continuous current imbalance in the sense coil or a ground fault current imbalance.

First claim

What is claimed is:

1. A method to continually self-test a ground fault detector comprising:
continuously drawing current for a ground fault detector circuit from a line conductor and a neutral conductor;
diverting the current for the ground fault detection circuit to cause a first current imbalance in a sense coil for a first half of a power-line cycle;
diverting the current for the ground fault detection circuit to cause a second current imbalance in the sense coil for a sec…

Assignees

• Texas Instruments Inc

Inventors

• Lewinski Artur J
• Teggatz Ross
• Cosby Thomas E

Classifications

• H02H3/335 Primary

  Electricity · mapped topic

• G01R35/00 Primary

  Physics · mapped topic