GB622799A - Improvements relating to fluorescent electric lighting systems - Google Patents

Abstract

622,799. Supply systems for discharge apparatus; transformers; inductance. MANDL, A., and METROPOLITAN-VICKERS ELECTRICAL CO., Ltd. April 10, 1947, No. 9589. [Classes 38 (ii) and 38 (iv)] In a lighting system with one terminal of each filamentary discharge electrode connected together through a condenser while the others are connected to the supply, a transformer has its primary in shunt to the condenser and the secondary open or short-circuited by a switch whereby the primary reactance of the transformer is low enough for heating current to pass with the secondary short-circuited and high enough to raise the condenser voltage for initiating the discharge when the secondary is open-circuited. As shown, short-circuiting of secondary of transformer 8 by switch 10 permits preheating of electrodes 1, 2 and open-circuiting enables voltage across condenser 4 to rise and initiate the discharge. Chokes 7, 9 may be connected as shown and may be on a common core with the transformer windings (primary coils 16, secondary coils 17) as shown in Fig. 2. Specification 601,809 is referred to.