Safety systems in apparatus for operating electric discharge devices

Claim 1

BALLAST TRANSFORMER APPARATUS FOR STARTING AND OPERATING A FLUORESCENT LAMP MOUNTED IN A CONDUCTIVE FIXTURE AND HAVING TWO SPACED ELECTRODES AT THE RESPECTIVE ENDS OF SAID LAMP COMPRISING, A HIGH REACTANCE TRANSFORMER INCLUDING A MAGNETIC CORE HAVING A PRIMARY WINDING AND A HIGH VOLTAGE SECONDARY WINDING THEREON AND MEANS PROVIDING LEAKAGE REACTANCE BETWEEN SAID WINDINGS, A PAIR OF INPUT LINES ON SAID PRIMARY WINDING FOR CONNECTION TO A SOURCE OF ALTERNATING CURRENT, A PAIR OF OUTPUT LINES ON SAID SECONDARY WINDING FOR RESPECTIVE CONNECTION TO THE ELECTRODES OF SAID LAMP, A HIGH RESISTANCE CONNECTED BETWEEN THE HIGH VOLTAGE END OF SAID PRIMARY WINDING AND THE LOW VOLTAGE END OF SAID SECONDARY WINDING, SAID WINDINGS BEING WOUND AND CONNECTED IN VOLTAGE ADDING RELATION, AND MEANS FOR CONNECTING THE LOW VOLTAGE END OF SAID PRIMARY WINDING IN CIRCUIT WITH SAID CONDUCTIVE FIXTURE WHEREBY SAID TRANSFORMER APPARATUS PROVIDES AUTOTRANSFORMER TYPE STARTING VOLTAGE AND ISOLATED TRANSFORMER TYPE RUNNING VOLTAGE FOR SAID LAMP.