GB419173A - An improved switching arrangement for lighting installations - Google Patents

Abstract

419,173. Supply and control systems for lamps. HAGELIN, B. C. W., 29, Lastmakaragatan, Stockholm. Dec. 29, 1933, No. 36633. [Class 38 (iv).] In a lighting installation, gaseous discharge tubes are connected in series either directly or over series connected transformers and some or all are provided with short-circuiting switches by means of which they are ignited or extinguished when required, the tubes being fed from a constant current device so that the current through them is kept constant irrespective of the number in use. Gaseous discharge tubes 1<a>, 1<b>-1<n> are arranged in series connected groups, provided with short-circuiting switches 2<a>-2<n>, and fed from transformers 3<a>, 3<n>, the primary windings of which are connected in series and provided with short-circuiting switches 7<a>, 7<n>. The transformers 3<a>, 3<n> are fed from a constant current device 4 which comprises an oscillating circuit composed of a reactance 4<a> and a condenser 4b while a reactance 4c is said to provide power factor correction. Resistances may be connected in series with the switches 2<a>-2<a>. In Fig. 1 (not shown), the discharge tubes are supplied through a transformer having a tapped choke in its primary circuit, the tapping switches of the choke being operated in conjunction with the tube short-circuiting switches to give a constant tube current. A tapped transformer may be used instead of the tapped choke.