Abstract: A method for operating a fluorescent lamp (5) having a nominal power (WLa) and stabilized with an EM ballast (B) comprises the steps of during normal operation, short-circuiting the lamp during a closing time interval (CTI) during each current period in order to operate the lamp at a reduced power. The method comprises the step of detecting whether the lamp is stabilized by means of an inductive ballast or by means of a capacitive ballast. If it is found that the ballast is capacitive, the timing of the closing time interval (CTI) is set such that the closing time interval (CTI) has a first closing time segment (CTS1) immediately before a zero-crossing of the current, having a first duration (?1) higher than zero, and a second closing time segment (CTS2) immediately after said zero-crossing of the current, having a second duration (?2) higher than zero.

Abstract: A method for operating a fluorescent lamp (5) having a nominal power (WLa) and stabilized with an EM ballast (B) comprises the steps of during normal operation, short-circuiting the lamp during a closing time interval (CTI) during each current period in order to operate the lamp at a reduced power. The method comprises the step of detecting whether the lamp is stabilized by means of an inductive ballast or by means of a capacitive ballast. If it is found that the ballast is capacitive, the timing of the closing time interval (CTI) is set such that the closing time interval (CTI) has a first closing time segment (CTS1) immediately before a zero-crossing of the current, having a first duration (?1) higher than zero, and a second closing time segment (CTS2) immediately after said zero-crossing of the current, having a second duration (?2) higher than zero.

Abstract: A low-pressure mercury vapor discharge lamp is provided with a discharge vessel (10). The discharge vessel comprises tubular end portions (11; 11′), which each have a longitudinal axis (12; 12′). The discharge vessel (10) encloses a discharge space (18) containing a filling of mercury and an inert gas in a gastight manner. Electrodes (20; 20′) are arranged in the discharge space (18). An auxiliary amalgam is provided on a carrier (25; 25′) in the proximity of the electrodes (20; 20′). According to the invention, a part of the carrier (25; 25′) is arranged in a plane transverse to the longitudinal axis (12; 12′). Preferably, a stem (21; 21′) in the tubular end portion (11; 11′) carries, apart from the electrode (20; 20′), a support in the form of a wire (23; 23′) or an extended exhaust tube, which support carries the carrier (25; 25′). In an alternative embodiment, the carrier is clamped directly onto the stem.