EP 0848580 B1 20000719 - Electronic ballast provided with a thermal safety circuit
Title (en)
Electronic ballast provided with a thermal safety circuit
Title (de)
Elektronisches Vorschaltgerät mit thermischer Schutzschaltung
Title (fr)
Ballast électronique avec circuit de protection thermique
Publication
Application
Priority
FI 965024 A 19961216
Abstract (en)
[origin: EP0848580A1] The invention relates to an electronic ballast provided with a thermal safety circuit, comprising a semi-bridge oscillator circuit (1, 2) and a transformer (3), which controls operation of the oscillator circuit and through which a high-frequency lamp current passes. The ballast is provided with a safety circuit (10), which prevents operation of the ballast as temperature and/or a voltage across the lamp exceeds a given value. The material and dimensioning for the core of the transformer (3) are selected in such a manner that the rise of the core temperature above a given temperature causes, as a result of saturation of the core, an increase in the operating frequency of the oscillator circuit. The safety circuit (10) includes elements for measuring a voltage existing across the lamp and elements for bringing the oscillator to an inactive or stand-by state as the measured voltage exceeds a given value. <IMAGE>
IPC 1-7
IPC 8 full level
H05B 41/285 (2006.01)
CPC (source: EP)
H05B 41/2855 (2013.01); H05B 41/2856 (2013.01)
Designated contracting state (EPC)
DE FR GB IT NL
DOCDB simple family (publication)
EP 0848580 A1 19980617; EP 0848580 B1 20000719; DE 69702588 D1 20000824; DE 69702588 T2 20010419; FI 101186 B1 19980430; FI 101186 B 19980430; FI 965024 A0 19961216
DOCDB simple family (application)
EP 97660142 A 19971211; DE 69702588 T 19971211; FI 965024 A 19961216