Abstract: An electronic ballast for at least one low-pressure discharge lamp contains an inverter which is connected to a direct-voltage source (UBUS), a load circuit which is connected to the inverter and contains the lamp (LA) and a series resonant circuit, and an evaluating circuit arrangement (M1) which reacts to different operating states of the lamp (LA) and in the case of a defect or removal of the lamp (LA) generates corresponding signals for switching off the inverter. A heating transformer, for heating the coils (W1, W2), the primary winding (Tp) of which is connected in series with a switch (S3) to the output of the inverter and in any case is connected to the direct-voltage source (UBUS) if the inverter is switched off on account of the heating-coil defect or the removal of the lamp (LA), with the switch (S3) being clocked in this off-phase.

Abstract: Process for the recognition of the rectifier effect appearing in a gas discharge lamp (G1, G2) and an electronic ballast, for the operation of gas discharge lamps (G1, G2), with which such a process finds employment. The electronic ballast includes a monitoring or control circuit (IC2) which monitors an operating parameter of a load circuit (E) of the electronic ballast, whereby this operating parameter corresponds to the lamp voltage or is dependent thereon. The monitoring circuit (IC2) integrates this monitored operating parameter over a full period and determines upon the presence of a rectifier effect if the integration result deviates from a predetermined integration desired value. Further, for the recognition of the rectifier effect, the duration of the positive and negative half-waves of the monitored parameter can be compared.

Abstract: An electronic ballast for a low-pressure discharge lamp (LA) contains an inverter that is fed with direct voltage (UBUS) and the output of which is connected to a load circuit containing terminal contacts for the lamp (LA), a heating transformer that has a primary winding (Tp), which is connected to the output of the inverter, and a respective secondary winding (Ts1, Ts2), which is located in a heating circuit with a coil (W1, W2), for heating each of the two electrodes of the lamp (LA), and a series circuit arrangement that is connected in parallel with the load circuit and which contains the primary winding (Tp) of the heating transformer and an electronic switch arrangement (S3, S4). For the purpose of identifying the type of lamp and the state of the lamp, the currents in one of the two heating circuits and in the primary winding (Tp) of the heating transformer are measured and evaluated.

Abstract: Method and device for controlling the operational performance of at least one gas discharge lamp (10). The control is effected with the aid of a controller (1) the proportional component of which is set in dependence upon an externally applied desired value (SOLL) of an operational parameter of the gas discharge lamp (10), whereby for low brightness desired values the proportional component of the controller (1) is set high, and for great brightness desired values of the gas discharge lamp (10) is set low. In this way it is possible to reliably fire the gas discharge lamp (10) even at low brightness values, without the appearance of a light flash, and at the same time to avoid instabilities in the case of high brightness values of the gas discharge lamp (10).

Abstract: Control device (3) for the operation of a load, in particular at least one gas discharge lamp (10, 15). The control device (3) is divided into a first purely software controlled control unit (3a) a second control unit (3b) realized purely in hardware. The two control units (3a, 3b) are connected with one another via a bidirectional connection line, the second control unit receiving exclusively internal operating state information (I.sub.intern) and the first control unit (3a) receiving external control information (I.sub.extern) By means of the division of the control device into a purely software controlled control unit (3a) and a control unit constructed purely of hardware (3b) the control device (3) in accordance with the invention has both a speed sufficient for rapid control procedures and also a sufficient flexibility with regard to alterations. Advantageously, the control device (3) in accordance with the invention is employed in an electronic ballast for the operation of gas discharge lamps (10, 15).

Abstract: Method for detecting the rectification effect in at least one gas discharge lamp (10) and electronic ballast for operating at least one gas discharge lamp, which recognises the appearance of the rectification effect in the gas discharge lamp (10). In order to be able to detect the appearance of the rectification effect in the gas discharge lamp (10) simply and with high sensitivity there is monitored the current (i.sub.1) flowing via a primary winding (7A), connected parallel to the gas discharge lamp (10), of a heating transformer (7A-C) or a parameter (i.sub.2, u.sub.3) dependent upon this current (i.sub.1) , and in the event that a predetermined limit value is overshot the presence of the rectification effect in the gas discharge lamp (10) is determined.

Abstract: An electronic ballast (EVG) is provided for operating at least one lamp (10), wherein a light sensor (20) for monitoring the brightness of a specific physical area (28) can be connected to the electronic ballast. A control arrangement (12) controls or regulates the brightness of the lamp (10) as a function of an actual brightness value delivered by the light sensor (20) and when the electronic ballast is put into operation automatically identifies whether a light sensor (20) is connected to the connection arrangement (18a, 18b).

Abstract: Gas discharge lamps are for regulated in a manner that is not affected by parasitic capacitances, such as line capacitances, by measuring current which passes through the lamp, calculating an active component of the measured current based on its phase in relation to a reference or by a comparison of the relative phases of the measured current and a voltage applied to the lamp, and regulating the lamp operation based on the active component.

Abstract: In accordance with the invention the circuitry arrangement comprises a central unit (5) and a plurality of peripheral units, such as control apparatuses for lamps, connected with the central unit via a data bus. These peripheral units are each connected with the data bus (1) via a coupling unit (3), each coupling unit (3) having a receiving branch for the transfer of information from the central unit (5) to the peripheral unit, and a transmission branch for the transfer of information from the peripheral unit to the central unit (5). Here, the central unit (5) sends out information in the form of a modulated a.c or pulse voltage onto the data bus. The transmission branch applies information to the data bus (1) in that the output resistance of the transmission branch is varied. Because the receiving branch in the coupling unit (3) is continuously active and the transmission branch is inactive in the case of non-sending operation, at most a very small return current is consumed in the coupling unit (3).

Abstract: There is provided a ballast for at least one gas discharge lamp havingan inverter which has two switches (S1, S2) in series, connected to a d.c. voltage source and switched with complementary timings, and a load circuit connected in parallel with one of the two switches (S1, S2) which load circuit includes a series resonant circuit (L1, C1) and the lamp (LA). Additionally there is provided a heating circuit (T, S3,R1) for current supply of the lamp coils, likewise connected to the inverter, which heating circuit includes a further periodically switchable switch (S3) for control of the heating current, whereby the heating circuit is likewise connected in parallel to one of the two switches of the inverter.

Abstract: There is provided an electronic ballast for supplying a load, for example a lamp, in particular a gas discharge lamp, with an a.c. voltage (Un) the frequency of which is higher than the mains frequency. The ballast has a rectifier (GL) to be connected to the a.c. mains, an inverter connected downstream thereof, having two switches (S2, S1), which inverter generates the higher frequency a.c. voltage for the load (Z), and an electronic harmonics filter arranged between the rectifier (GL) and the inverter, in the form of a clocked switching controller. The control switch (S1) of the clocked switching controller at the same time forms one of the two switches (S1) of the inverter.

Abstract: A control system for gas discharge lamps (5) includes a fuzzy controller (7) which, for controlling the lamp current of the gas discharge lamp, generates a setting value for an inverter (3), for setting the frequency or duty ratio of the lamp current, in dependence upon an actual value of the lamp current. Further, in accordance with the invention, fuzzy logic is employed for the purpose of recognition of the lamp type of a connected gas discharge lamp (5), in that on the basis of various detected operational parameter values, during the operation of the gas discharge lamp, the lamp type of the gas discharge lamp is determined.

Abstract: An electronic ballast (2) which includes an electronic harmonics filter (7), the brightness of a lamp (38) can be determined by employment of a dimmer (1) provided in the mains feed, in that a desired value signal (UM) for setting the frequency (f) of the switch (S) is supplied to the controller (8), which desired value signal depends upon the input or output voltage of a rectifier (4) connected downstream of the dimmer (1), in particular dependent upon the curve form of this voltage.

Abstract: There is disclosed a control arrangement for plural consumer units allocated to groups for operation by means of operating elements connected with at least one group address control transmitter. The transmitter transmits group addresses to control receivers which are connected to customer units and in which group addresses are stored during a commissioning phase, whereby after such commissioning, consumer units are connected in groups with associated control receivers according to the operation of an operating element.

Abstract: The application relates to a ballast for the pulsed-mode operation of gas discharge lamps (EVG) and a use of a self-excited or externally controlled half or full bridge circuit for the same purpose. An EVG of the mentioned kind has a buffered feed d.c. voltage (U.sub.dc, udc) from which the utilized power for the GE lamp or GE lamps can be derived. The load circuit in which the GE lamps are provided has a series-connected choke (L1), if necessary a capacitor (C1) can be connected in parallel to the lamp for ignition purposes. Such a circuit is to be so configured that it is possible to change the characteristic light values, i.e. the light output and the color temperature of the gas discharge lamps (GE). This is to be realized without mechanical choke switching and is achieved in that at least one electronic switching element (S1) or at least one such switching element pair (S1, S2, S3, S4) are provided which supply the choke (L1) and the GE lamp periodically with voltage pulses (u.sub.ac).