05930130 is referenced by 28 patents and cites 7 patents.

A large inrush of electrical current flow occurs during a short interval after switch closure, when power is applied to a conventional electronic ballast commonly used for fluorescent lighting. This inrush current flows as the main filter capacitor in the ballast charges to its steady state value. For a lighting circuit that contains a multiplicity of ballasts, the combined magnitude of the inrush is potentially large enough to cause contact failure of the switching device due to arcing and contact welding. The invention features a circuit for limiting inrush current having a current-limiting resistor that is active for a brief interval during startup. The resistor is subsequently bypassed from the principal current path by a switching transistor. The transistor is controlled by electrical signals normally present in conventional electronic ballasts. The advantage of the inventive circuitry is the use of only two inexpensive components to accomplish inrush current protection.

Title
Inrush protection circuit
Application Number
8/940067
Publication Number
5930130
Application Date
September 29, 1997
Publication Date
July 27, 1999
Inventor
David W Dranchak
Endwell
NY, US
Robert M Murcko
Binghamton
NY, US
Robert H Katyl
Vestal
NY, US
Agent
Salzman & Levy
Assignee
JRS Technology
NY, US
IPC
G05F 1/10
H02M 5/42
H02H 7/125
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