DE102010001917A1 - Circuit arrangement for operating at least one lamp - Google Patents

Abstract

The present invention relates to a circuit arrangement for operating at least one light source (La1) comprising: an input having a first phase connection (L1) for coupling to a first phase of a three-phase supply network, a second phase connection (L2) for coupling to a second phase the three-phase supply network, a dimming signal input terminal (K) for coupling to a source for a dimming signal, the source for a dimming signal comprising a dimming switch (DIM) connected in series between a terminal to a third phase (L3) of the three-phase Supply network and the dimming signal input terminal (K), and a neutral terminal (N) for coupling to the neutral of the three-phase supply network; at least one first processing device (VA1), the first processing device (VA1) comprising: a first input terminal coupled to a first one of the phase terminals (L1) of the circuit arrangement; a second input terminal coupled to the dimming signal input terminal (K) of the circuit arrangement; a third input terminal coupled to the neutral terminal (N) of the circuitry; a rectifier (GL1) having first and second rectifier input terminals, the first rectifier input terminal being coupled to the first input terminal, the second rectifier input terminal being coupled to the third input terminal, and first and second rectifier output terminals (GND), an electronic ballast ( EVG1) coupled to the supply to the first and second rectifier output terminals (GND), the potential at the second rectifier output terminal (GND) representing the reference potential for the electronic ballast (EVG1), the electronic ballast (EVG1) having a dimming input (St1 ), wherein the electronic ballast (EVG1) comprises an output for connecting the at least one light source (La1); a voltage divider (RL11, RL12) serially coupled between the second input terminal and the second rectifier output terminal (GND), the tap point (A1) of the voltage divider (RL11, RL12) coupled to the dimming input (St1) of the electronic ballast (EVG1) is; wherein the at least one first processing device (VA1) comprises a diode (D1) serially coupled between the second input terminal and the voltage divider (RL11, RL12) of the at least one first processing device (VA1).

Description

Technical area

The present invention relates to a circuit arrangement for operating at least one lighting means. It is illustrated by the example of street lighting, but, as would be apparent to one skilled in the art, is also transferable to other areas.

State of the art

1 shows in this context a known from the prior art circuit arrangement for street lighting. In this case, a rectifier GL1 is connected on the input side to a first phase L1 of a three-phase supply network and to the neutral conductor of the three-phase supply network. The output of the rectifier GL1 is coupled to the supply with an electronic ballast EVG1, which in turn supplies at least one lamp La1. In the example of street lighting mentioned above, the lamp power is often reduced to save energy during the night. For this purpose a switching line with mains potential is used. In the present case, a signal for a control input St1 of the electronic ballast EVG1 is generated by means of a dimming switch DIM. The signal provided at the control input St1 of the electronic ballast EVG1 is evaluated with regard to the duration of the actuation of the dimming switch DIM or the number of actuations of the dimming switch DIM and a corresponding dimming of the lamp La1 is undertaken. For this purpose, a microprocessor is present in the electronic ballast, which counts, for example, the number of mains waves during the pressing of the dimming switch DIM. The microprocessor may in particular be designed to interpret a short press as on / off and a longer press as a dimming request.

Between the dimming switch DIM and the rectifier output terminal GND of the rectifier GL1 is coupled a voltage divider comprising the resistors RL11 and RL12. The tapping point A1 of the voltage divider is coupled to the control input St1 of the electronic ballast EVG1. The rectifier output terminal GND of the rectifier GL1 represents the reference potential for the electronic ballast EVG1.

For cost and wiring reasons, it is desirable for all lights only one switching line, that is to provide only a dimming switch, although in the three-phase system, several ECGs are provided, which are supplied from a rectifier, which is not fed by the phase, with which the dimming switch DIM is coupled. In order to prevent interference between the lights, a relay is installed in the prior art in each lamp. By means of the respective relay, the phase present in the respective luminaire, that is to say the phase from which the rectifier of the respective luminaire is supplied, is coupled to the control input St1 of the respective electronic ballast EVG. However, the installation of the relays results in considerable additional costs.

An alternative solution is to use a plurality of switching lines, that is one switching line per phase. However, this results in increased wiring and unwanted additional costs.

Presentation of the invention

The object of the present invention is to provide a circuit arrangement in which, despite the use of at least two phases of a three-phase network for the supply of electronic ballasts mutual interference is excluded, the circuit arrangement without relay and with only one switching line to get along ,

This object is achieved by a circuit arrangement having the features of patent claim 1.

According to the invention, a circuit arrangement for operating at least one luminous means comprises an input with a first phase connection for coupling to a first phase of a three-phase supply network, a second phase connection for coupling to a second phase of the three-phase supply network, a dimming signal input connection for coupling to one A source for a dimming signal, the source of a dimming signal comprising a dimming switch serially coupled between a terminal to a third phase of the three-phase supply network and the dimming signal input terminal, and a neutral terminal for coupling to the neutral of the three-phase supply network , It further comprises at least one first processing device, which in turn comprises: a first input terminal coupled to a first one of the phase terminals of the circuit arrangement; a second input terminal coupled to the dimming signal input terminal of the circuit arrangement; a third input terminal coupled to the neutral terminal of the circuit arrangement; a rectifier having a first and a second rectifier input terminal, wherein the first rectifier input terminal is coupled to the first input terminal, wherein the second Rectifier input terminal is coupled to the third input terminal, and a first and a second rectifier output terminal; an electronic ballast coupled for supply to the first and second rectifier output terminals, the potential at the second rectifier output terminal representing the reference potential for the electronic ballast, the electronic ballast comprising a dimming input, the electronic ballast having an output for connecting the at least one And a voltage divider serially coupled between the second input terminal and the second rectifier output terminal, wherein the tap point of the voltage divider is coupled to the dimming input of the electronic ballast. According to the invention, the first processing device further comprises a diode, which is serially coupled between the second input terminal and the voltage divider of the at least one first processing device.

The findings underlying the present invention are with reference to 2 shown. 2 shows accordingly 1 a first assembly in which the rectifier GL1 is coupled to the first phase L1 of a three-phase supply network and the neutral. It also shows a second assembly in which a rectifier GL2 is coupled to a second phase L2 of the three-phase supply network and neutral. The switching line is formed by a dimming switch DIM being coupled between the third phase L3 of the three-phase supply network and a node K, the node K being connected to the voltage divider RL11, RL12 of the first module and the voltage divider RL21, RL22 of the second module is coupled.

In the three-phase supply network, the phases L1, L2, L3 are known to be offset by 120 ° from each other. If the control inputs St1, St2 of the two modules are coupled at point K, equalizing currents I _a flow, without the dimming switch DIM being activated, depending on the respective phase position of the phases L1, L2. In the in 2 For example, if the instantaneous voltage of phase L2 is positive, the instantaneous voltage of phase L1 is negative. As a result, a compensating current I _{a flows} from the phase L2, via the rectifier GL2; the rectifier output terminal GND of the rectifier GL2, the voltage divider RL22, RL21, via the node K to the voltage divider RL11, RL12 and then to the rectifier output terminal GND of the rectifier GL1. As a result, a signal is generated at the tapping point of the voltage divider RL11, RL12, which is interpreted as a dimming signal after appropriate evaluation in the electronic ballast EVG1, although the dimming switch DIM was not pressed. At other times, that is, at different phase, it comes to other equalization currents. This leads to unpredictable dimming and blinking effects that vary continuously.

On the basis of this knowledge, according to the present invention, the flow of equalizing currents and thus unwanted dimming and blinking effects are prevented by coupling a respective diode between the node K and the respective voltage divider. By appropriate orientation of the diode only a current flow in the direction is possible, which is required when pressing the dimming switch DIM to apply a dimming signal to the respective control input of the respective electronic ballast. This compensating currents and their undesirable effects are effectively prevented. The use of expensive relays can be dispensed with. The fact that only one switching line is needed, the wiring costs compared to the prior art can be significantly reduced.

In a preferred embodiment, the diode is arranged such that the anode of the diode is coupled to the second input terminal of the at least one first processing device and the cathode of the diode is coupled to the associated voltage divider. This effectively prevents the flow of reverse compensation currents.

In a further development of a circuit arrangement according to the invention, at least one second processing device is furthermore provided, wherein the first input connection of the second processing device is coupled to the phase connection, which is not coupled to the first input connection of the first processing device.

Finally, the input of the circuitry may include a third phase terminal for coupling to a third phase of the three-phase supply network, the circuitry further comprising a third processing device, wherein the first input terminal of the third processing device is coupled to the third phase terminal. As a result, all three phase connections of the three-phase supply network can be used to supply electronic ballasts without any mutual interference and thus disruption.

Short description of the drawing (s)

In the following, an embodiment of the present invention will now be described in detail with reference to the accompanying drawings. Show it:

1 a schematic representation of a known from the prior art circuit arrangement for operating at least one lamp;

2 a schematic of a study with preliminary considerations for the representation of the compensation currents, which lead to unwanted dimming and blinking effects;

3 a schematic representation of a first embodiment of a circuit arrangement according to the invention; and

4 in a schematic representation of a second embodiment of a circuit arrangement according to the invention.

Preferred embodiment of the invention

3 shows a schematic representation of an embodiment of a circuit arrangement according to the invention. This example is essentially the same as in 2 presented study with preliminary considerations, so that with reference to 2 introduced reference numerals for the in 3 illustrated embodiment taken and not reintroduced.

In contrast to the representation of 2 is at the in 3 illustrated embodiment of a circuit arrangement according to the invention between the point K and the respective voltage divider RL11, RL12 or RL21, RL22 each inserted a diode D1 or D2, wherein the respective diode D1, D2 is arranged so that only more a current flow from the dimming switch DIM in the direction of respective voltage divider RL11, RL12 or RL21, RL22 is made possible. Thus, the flow of equalizing currents I _a , see 2 , effectively prevented. Only one current flow I _s from the switching line to the respective voltage divider is possible.

The voltage divider RL11, RL12, the rectifier GL1 and the EVG1 are in a first processing device VA1, the voltage divider RL21, RL22, the rectifier GL2 and the EVG2 are combined in a second processing device VA2.

In the 4 In the embodiment shown, with respect to the signal provided to the evaluation unit at the respective control input St1, St2, the signal inverse to that in FIG 3 constructed embodiment. The processing units VA1, VA2 further comprise a voltage source + U for supplying a positive supply voltage. Between the respective connection to the voltage source + U and the respective voltage divider another ohmic resistance is coupled; in the case of the processing unit VA1 the ohmic resistance R _L13 , in the case of the processing unit VA2 the ohmic resistance R _L23 . Optionally, protective diodes D3, D4 can furthermore be provided, which are connected in parallel to the respective voltage divider.

As a result of these measures, a voltage value is established in normal operation via the voltage divider at the respective control input St1, St2. The electronic ballast EVG1, EVG2 detects a signal. When the dimming switch DIM is triggered, current flow in the respective voltage divider is interrupted at low or negative voltage at phase L3. This reduces the voltage at the respective control input St1, St2 to zero volts. At the missing signal at the respective control input St1, St2, the respective electronic ballast EVG1, EVG2 detects that the dimming switch DIM has been actuated.

In one embodiment, not shown, in the 3 and 4 illustrated embodiments extended by a further processing device whose rectifier is coupled to the neutral and the third phase L3, see the illustration of 1 when replacing L1 with L3.

The dimming switch DIM can be designed in all embodiments as a sensing device or as a switch.

Claims (4)

Circuit arrangement for operating at least one light source (La1) comprising: - an input with a first phase connection (L1) for coupling to a first phase of a three-phase supply network, a second phase connection (L2) for coupling to a second phase of the three-phase Supply network, a dimming signal input terminal (K) for coupling to a source for a dimming signal, wherein the source for a dimming signal comprises a dimming switch (DIM) connected in series between a terminal to a third phase (L3) of the three-phase supply network and the Dimming signal input terminal (K) is coupled, and a neutral terminal (N) for coupling to the neutral of the three-phase supply network; - At least a first processing device (VA1), wherein the first processing device (VA1) comprises: - a first input terminal which is coupled to a first of the phase terminals (L1) of the circuit arrangement; A second input terminal coupled to the dimming signal input terminal (K) of the circuit arrangement; A third input terminal coupled to the neutral terminal (N) of the circuit arrangement; A rectifier (GL1) having first and second rectifier input terminals, the first rectifier input terminal being coupled to the first input terminal, the second rectifier input terminal being coupled to the third input terminal, and first and second rectifier output terminals (GND), - electronic Ballast (EVG1) coupled to the first and second rectifier output terminal (GND) for supply, the potential at the second rectifier output terminal (GND) representing the reference potential for the electronic ballast (EVG1), the electronic ballast (EVG1) having a dimming input (St1), wherein the electronic ballast (EVG1) comprises an output for connecting the at least one light source (La1); A voltage divider (RL11, RL12) serially coupled between the second input terminal and the second rectifier output terminal (GND), the tap point (A1) of the voltage divider (RL11, RL12) being connected to the dimming input (St1) of the electronic ballast (EVG1) is coupled; wherein the at least one first processing device (VA1) comprises a diode (D1) serially coupled between the second input terminal and the voltage divider (RL11, RL12) of the at least one first processing device (VA1). Circuit arrangement according to claim 1, characterized in that the diode (D1) is arranged such that the anode of the diode (D1) with the second input terminal of the at least one first processing device (VA1) and the cathode of the diode (D1) with the voltage divider ( RL11, RL12) is coupled. Circuit arrangement according to one of claims 1 or 2, characterized in that the circuit arrangement further comprises at least one second processing device (VA2), wherein the first input terminal of the second processing device (VA2) is coupled to the phase terminal (L2) which is not connected to the first input terminal the first processing device (VA1) is coupled. Circuit arrangement according to one of the preceding claims, characterized in that the input of the circuit arrangement comprises a third phase connection (L3) for coupling to a third phase of the three-phase supply network, wherein the circuit arrangement further comprises a third processing device, wherein the first input terminal of the third Processing device is coupled to the third phase connection.

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