Electricity: electrical systems and devices – Safety and protection of systems and devices – Ground fault protection
Patent
1997-09-26
1999-06-22
Nguyen, Matthew
Electricity: electrical systems and devices
Safety and protection of systems and devices
Ground fault protection
361 45, 363 15, H02H 300, H02J 100
Patent
active
059148420
ABSTRACT:
In an electrical power supply system provided with a step-down distribution transformer connected to a power source to supply current to at least one neutral grounded load center, said power source having a conductor connected to a first primary grounding connection, said distribution transformer having a magnetic core, and a primary and a secondary winding independently mounted on said magnetic core, said secondary winding being electrically connected to a pair of output terminals and to a center-tapped neutral terminal, said terminals being connected to said load center, said primary winding being electrically connected to a pair of input terminals arranged for connection to said primary power source, one of said input terminals being further connected to a second primary grounding connection, said center-tapped neutral terminal being connected to said second primary grounding connection via a shunting conductor, an improvement comprising a current balancing transformer (CBT) having a magnetic core and a first and a second independent winding wound thereon, said current balancing transformer being located between said primary power source and said distribution transformer, said first CBT winding having one end connected to said primary power source and its opposite end being connected to the primary winding of said distribution transformer, a said second CBT winding being directly connected to said primary power source at one end and having its opposite end connected to the primary winding of said distribution transformer with the purpose of substantially eliminating stray voltage in an electrical load circuit comprising the steps of: locating a current balancing transformer (CBT) between a primary power source and a step-down distribution transformer, connecting one end of said first CBT winding to a power source and connecting the opposite end thereof to one end of said primary winding; connecting an end of said second CBT winding to said power source and also to a first primary grounding connection; connecting the opposite end of said second CBT winding to the opposite end of said primary winding; connecting said second CBT winding, said opposite end of said primary winding and said center-tapped conductor to a second primary grounding connection; and connecting opposite ends of said secondary winding and said center-tapped terminal to a secondary grounded load center to be supplied by said power source and said step-down transformer.
REFERENCES:
patent: 2087340 (1937-08-01), Davis
patent: 3855501 (1974-12-01), Agnew
patent: 4091431 (1978-05-01), Morris
patent: 4227461 (1980-10-01), Beezley et al.
patent: 4243842 (1981-01-01), Gibb
patent: 4356435 (1982-10-01), Kalmanash
patent: 4428018 (1984-01-01), Hahn
patent: 4456834 (1984-06-01), Harris
patent: 4573098 (1986-02-01), Williston
patent: 4816956 (1989-03-01), Hertz et al.
patent: 5536978 (1996-07-01), Cooper et al.
patent: 5594329 (1997-01-01), Van Ettinger et al.
Nguyen Matthew
SNC Manufacturing Co., Inc.
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