GB720279A - Improvements in or relating to circuits for operating electric discharge lamps - Google Patents
Improvements in or relating to circuits for operating electric discharge lampsInfo
- Publication number
- GB720279A GB720279A GB1879751A GB1879751A GB720279A GB 720279 A GB720279 A GB 720279A GB 1879751 A GB1879751 A GB 1879751A GB 1879751 A GB1879751 A GB 1879751A GB 720279 A GB720279 A GB 720279A
- Authority
- GB
- United Kingdom
- Prior art keywords
- ballast
- reactor
- capacitor
- series
- inductance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
- H05B41/14—Circuit arrangements
- H05B41/36—Controlling
- H05B41/38—Controlling the intensity of light
- H05B41/39—Controlling the intensity of light continuously
Landscapes
- Discharge-Lamp Control Circuits And Pulse- Feed Circuits (AREA)
Abstract
720,279. Supply systems for space-discharge apparatus. GENERAL ELECTRIC CO., Ltd., and CATES, J. Oct. 31, 1952 [Aug. 9, 1951], No. 18797/51. Class 38 (4). Dimming of one or more electric-discharge lamps 1 is effected by a circuit arrangement supplied with A.C. at variable frequency and including a frequency-dependent ballast impedance comprising effectively a capacity C1 and an inductance L in series with each other and with the lamps and a reactor, in the embodiment shown a capacitor C2, in parallel with one or both the capacity and inductance, the one being of opposite sign to the reactor, the arrangement being such that the lamp is dim at the supply frequency at which the ballast impedance is parallel-resonant, and operates at high brightness, in series with the ballast impedance which is then effectively of opposite sign from the reactor, at supply frequencies which are either more or less than the resonant frequency depending upon whether the reactor is inductive or capacitive respectively. In the inductive ballast impedance shown in Fig. 3, the inductance L may be split into two parts with the capacitor C1 interposed, and complementary circuits are described for capacitive ballast impedances. The addition of capacitor C1 or inductor L permits an increase in the ballast inductance value relative to that of the shunting reactor, thereby decreasing the resonant circuit current and hence the minimum lamp current, which latter may be further decreased by the provision of a seriesconnected capacitor 12 and resistor 13 to shunt the lamp 1. Dimming may additionally be effected by conventional variation of voltage amplitude. The arrangement is applicable to cold-cathode as well as to the hot-cathode lamp shown, and a plurality of lamps may be series or parallel connected, having a common or separate ballast impedances respectively. Power-factor correction is effected in a capacitive circuit by a transductor, and in an inductive circuit by a transductor in series with a condenser, the current in the transductor control windings being arranged to vary with variations of supply frequency.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1879751A GB720279A (en) | 1951-08-09 | 1951-08-09 | Improvements in or relating to circuits for operating electric discharge lamps |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1879751A GB720279A (en) | 1951-08-09 | 1951-08-09 | Improvements in or relating to circuits for operating electric discharge lamps |
Publications (1)
Publication Number | Publication Date |
---|---|
GB720279A true GB720279A (en) | 1954-12-15 |
Family
ID=10118590
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1879751A Expired GB720279A (en) | 1951-08-09 | 1951-08-09 | Improvements in or relating to circuits for operating electric discharge lamps |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB720279A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1151600B (en) * | 1961-10-07 | 1963-07-18 | Siemens Ag | Circuit arrangement for the lighting of streets with full and reduced illuminance with low voltage fluorescent lamps |
FR2434547A1 (en) * | 1978-08-25 | 1980-03-21 | Esquire Inc | VARIABLE LOW-FREQUENCY GRADATION FOR HIGH-INTENSITY GAS DISCHARGE LAMPS |
US4396872A (en) * | 1981-03-30 | 1983-08-02 | General Mills, Inc. | Ballast circuit and method for optimizing the operation of high intensity discharge lamps in the growing of plants |
-
1951
- 1951-08-09 GB GB1879751A patent/GB720279A/en not_active Expired
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1151600B (en) * | 1961-10-07 | 1963-07-18 | Siemens Ag | Circuit arrangement for the lighting of streets with full and reduced illuminance with low voltage fluorescent lamps |
FR2434547A1 (en) * | 1978-08-25 | 1980-03-21 | Esquire Inc | VARIABLE LOW-FREQUENCY GRADATION FOR HIGH-INTENSITY GAS DISCHARGE LAMPS |
US4396872A (en) * | 1981-03-30 | 1983-08-02 | General Mills, Inc. | Ballast circuit and method for optimizing the operation of high intensity discharge lamps in the growing of plants |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB720279A (en) | Improvements in or relating to circuits for operating electric discharge lamps | |
US2497534A (en) | Circuits for high-frequency operation of fluorescent lamps | |
GB1528910A (en) | Discharge lamp ballast circuits | |
JPS56157261A (en) | Power source | |
GB760674A (en) | Improvements relating to starting circuits for electric discharge lamps | |
GB744819A (en) | Improvements in or relating to electric circuit arrangements for starting and operating from an alternating current supply a pair of heatable-cathode low pressure electric discharge lamps | |
US3189787A (en) | Ignition circuit for gas discharge tubes | |
GB713784A (en) | Improvements in or relating to circuit arrangements for operating low pressure electric discharge lamps | |
GB755776A (en) | Improvements in or relating to electric circuits for starting and operating fluorescent lamps | |
AT226323B (en) | Device for adjusting the power consumption of gas and / or vapor discharge lamps | |
GB744820A (en) | Improvements in or relating to electric circuit arrangements for starting and operating from an alternating current supply a pair of low pressure electric discharge lamps | |
US5339004A (en) | Regulating ballast with power factor correction for high-frequency gaseous discharge lamps | |
GB1325361A (en) | Electrical heating devices | |
GB730024A (en) | Improvements in or relating to circuit arrangements for operating electric dischargelamps having heatable electrodes | |
GB1466215A (en) | Electric circuit arrangement for operating a high pressure sodium discharge lamp | |
GB595697A (en) | Improved apparatus for electric arc welding | |
GB758455A (en) | Improvements in or relating to electric circuits for discharge lamps | |
GB703255A (en) | Improvements in electric circuit arrangements for operating low pressure electric discharge lamps having preheatable electrodes | |
GB702836A (en) | Improvements in or relating to circuit arrangements for operating electric dischargelamps | |
GB601809A (en) | Improvements relating to fluorescent electric lighting | |
GB631730A (en) | Improvements in and relating to circuits for a plurality of electric discharge lamps | |
GB1493330A (en) | Discharge lamp operating circuit | |
GB713734A (en) | Improvements in supply circuits for electric discharge tubes | |
GB514547A (en) | Improvements in supply systems for high-voltage high-frequency apparatus | |
GB611810A (en) | Improvements in or relating to the control of alternating currents in parallel-connected load-circuits |