US 12,334,722 B2
Ground fault circuit interrupter (GFCI) devices, systems, and methods
Kenneth Riehl, North Liberty, IA (US); Joseph Hall, Colorado Springs, CO (US); Juan Ignacio Melecio, North Liberty, IA (US); Jeremy D. Schroeder, Cedar Rapids, IA (US); and Jacob B. Guelff, Cedar Rapids, IA (US)
Assigned to Schneider Electric USA, Inc., Boston, MA (US)
Filed by Schneider Electric USA, Inc., Andover, MA (US)
Filed on Jan. 24, 2023, as Appl. No. 18/101,060.
Claims priority of provisional application 63/436,436, filed on Dec. 30, 2022.
Prior Publication US 2024/0222954 A1, Jul. 4, 2024
Int. Cl. H02H 3/33 (2006.01); H01H 83/14 (2006.01); H02H 3/16 (2006.01)
CPC H02H 3/331 (2013.01) [H01H 83/144 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A ground fault circuit interrupter (GFCI), comprising:
a current transformer (CT) comprising:
a single core;
a ground fault (GF) sense winding wound around the single core; and
a test winding wound around the single core;
a GF detection module operatively connected to the GF sense winding to receive signals from the GF sense winding and configured to determine whether a line-to-ground fault exists;
a test signal stimulus operatively connected to the test winding to supply a test signal to the test winding when activated such that the test signal is coupled onto the GF sense winding via the CT and detected by the GF detection module which receives the signal from the GF sense winding to determine if the CT and a GF signal chain is operating correctly; and
a grounded neutral (GN) detection module operatively connected to at least one winding of the CT and configured to receive signals from the at least one winding to determine whether a neutral-to-ground fault exists, wherein the at least one winding of the CT that is operatively connected to the GN detection module is the test winding such that the GN detection module is configured to receive signals from the test winding to determine whether the neutral-to-ground fault exists.