Abstract:
An apparatus for controlling at least one electrical load may include at least one pushbutton; a communications interface for communicating with the loads, the loads being switched on and off by the at least one pushbutton via the communications interface; and a first controlled switch with control logic, said switch being connected between the loads and a power supply, and the first controlled switch isolates the power supply from the loads as soon as all of the loads have been disconnected via the communications interface.

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to an apparatus for controlling at least one electrical load, with at least one pushbutton, and a communications interface for communicating with the loads, the loads being switched on and off by the at least one pushbutton via the communications interface. 
       PRIOR ART 
       [0002]    The invention is based on an apparatus for controlling at least one electrical load in accordance with the generic type of the main claim. 
         [0003]      FIG. 10  shows a conventional installation of loads, in this case electronic control gear for light-emitting means in accordance with the prior art. The electronic control gear are connected to a power supply (N, PE) and are switched on and off via a communications interface (DA). A conventional protocol in this sector is the DALI (Digital Addressable Lighting Interface) protocol. A preferred functionality of the communications interface in relatively small installations is the so-called touch-dim function, which is also controlled by many devices with a DALI interface. A pushbutton is used for this purpose. If the pushbutton is depressed for only a short period of time, the control gear switches the one or more light-emitting means on or off. If the pushbutton is depressed for a relatively long period of time when the light-emitting means are switched on, the light-emitting means are faded up or down. In the case of both a short depression and a relatively long depression of the pushbutton, the function which is respectively complementary to the preceding function is implemented. If the light-emitting means are in operation, they are switched off by a short depression of the pushbutton. If they are switched off, they are switched on by a short depression of the pushbutton and so on. If the light-emitting means are switched on and the pushbutton is depressed for a relatively long period of time, the light-emitting means are faded down. In the case of the next relatively long depression of the pushbutton they are faded up again. The present dimming position can be stored in the device by a “double click”, i.e. two depressions of the pushbutton in quick succession. 
         [0004]    The switching-on and switching-off operations can take place at any desired point in time, as can other DALI/touch-dim commands, which means that the electronic control gear need to be constantly communications-ready. The electronic control gear therefore need to have a constant supply of power. This applies in particular also when the light-emitting means of an electronic control gear has been switched off by a DALI/touch-dim command and is in the standby mode. 
         [0005]    The above described permanent power supply to electronic control gear results in a high level of undesired power consumption in the standby mode, in particular in the case of large lighting installations. 
         [0006]    Relatively large lighting installations are isolated from the power supply system manually or via timer switches in order to reduce the power consumption in the standby mode when it is ensured that they are not required (for example at night). During conventional use times of the installation, however, all of the parts of the installation are supplied with power from the power supply system. Unused parts of the installation are then in the standby operating mode and thus cause an undesirable additional power consumption. 
         [0007]    Isolating the lighting installation from the power supply system manually or in a controlled manner via timer switches, as has previously been the practice, in order to save energy also has the disadvantage that the lighting installation can only be activated by additional working steps, if said lighting installation is required during this time as an exception. 
       OBJECT  
       [0008]    The object of the invention is to specify an apparatus which controls the loads in such a way that the standby losses are reduced. 
         [0009]    The object is achieved according to the invention by the features of claim  1 . 
         [0010]    A further object of the invention is to specify a method by means of which one or more loads can be controlled in such a way that the standby losses of the loads are reduced. 
         [0011]    This object is achieved according to the invention by the features of method claim  10 . 
       DESCRIPTION OF THE INVENTION 
       [0012]    Further advantageous developments and configurations of the apparatus according to the invention for controlling electrical loads result from the dependent claims and the description below. 
         [0013]    According to the invention, the pushbutton which controls the loads is extended by control logic and a first controlled switch. This first controlled switch is connected between the power supply and the loads. It preferably switches the phase of the power supply. A second controlled switch serves the purpose of passing the pulse sequences generated by the pushbutton onto the loads via an output of the apparatus. The control logic knows the switching states of the loads and identifies specific switching operations. If the loads are switched on, and the pushbutton is depressed for a short period of time, the loads are switched off via the communications interface, and the controlled switch is then opened for a short period of time in order to isolate the power supply from the loads and from the control logic of the controlled switch. If the pushbutton is depressed again, the controlled switch is closed and the power supply is applied to the control logic and to the loads. Shortly after this, the switch-on signal generated by the pushbutton is passed on by the second controlled switch in order to switch on the loads. All of the other operations which relate to the touch-dim functionality are passed on directly from the pushbutton to the loads by the second controlled switch. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING(S) 
         [0014]    The invention will be explained in more detail below with reference to exemplary embodiments. In the drawings: 
           [0015]      FIG. 1  shows an installation with the apparatus according to the invention in a first embodiment for supplying power to loads. 
           [0016]      FIG. 2  shows some relevant signals of the apparatus according to the invention. 
           [0017]      FIG. 3  shows an installation with the apparatus according to the invention in a second exemplary embodiment for supplying power to loads. 
           [0018]      FIG. 4  shows the assignment of the terminals of the apparatus according to the invention in the second embodiment. 
           [0019]      FIG. 5  shows a circuit arrangement of the power section of the apparatus according to the invention. 
           [0020]      FIG. 6  shows a schematic illustration of a digital control logic with a microcontroller of the apparatus according to the invention. 
           [0021]      FIG. 7   a  shows an illustration of the circuitry for analog control logic of the apparatus according to the invention. 
           [0022]      FIG. 7   b  shows a state table for the analog control logic of the apparatus according to the invention. 
           [0023]      FIG. 8  shows an illustration of the driving of the controlled switches of the apparatus according to the invention. 
           [0024]      FIG. 9  shows a circuit arrangement of the power section in a further variant of the apparatus according to the invention. 
           [0025]      FIG. 10  shows an installation for controlling loads in accordance with the prior art. 
           [0026]      FIG. 11  shows a flow chart for illustrating the internal functional sequences in the digital control logic shown in  FIG. 6 . 
           [0027]      FIG. 12  shows a sequence diagram with the exemplary illustration of a plurality of operations and the associated signals. 
       
    
    
     PREFERRED EMBODIMENT OF THE INVENTION 
       [0028]    A first embodiment  31  of the apparatus according to the invention is shown in  FIG. 1 . The loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  are all connected to a power supply system, which has a looped-through neutral conductor N and a looped-through ground conductor PE. The phase  55  is switched by the first controlled switch  23 . The first controlled switch is driven by control logic  21 . The apparatus according to the invention has an input for one or more pushbuttons T 1 -T n , which are each connected in parallel. The pushbutton(s) T 1 -T n  generate an input signal  511 . The loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  are controlled via the pushbutton(s) T 1 -T n  preferably by means of the touch-dim method mentioned at the outset. 
         [0029]      FIG. 2  illustrates some signals which relate to the apparatus according to the invention. Signal  511  is the input signal generated by the pushbuttons T 1 -T n . The control logic identifies that a pushbutton has been depressed once and switches on the first controlled switch  23  in order to apply the power supply, illustrated by the signal  55 , to the loads. Shortly after the power supply has been switched on (approximately 200 ms), the switch-on signal is reproduced at the control output (signal  53 ). As long as the loads are switched on, all of the operations which are generated by one of the pushbuttons T 1 -T n  are looped through or reproduced with a delay. Only a single depression of the pushbutton is identified by the control logic, and thereupon the loads are switched off and then the power supply is isolated by opening the first controlled switch  23 . 
         [0030]    In a second embodiment shown in  FIG. 3 , the apparatus according to the invention is provided as an integrated solution  33  for installation in a flush-mounted box, for example. A pushbutton T is integrated in the apparatus which has the assignment of terminals illustrated in  FIG. 4 . The apparatus contains a system phase L and a neutral conductor N as inputs. Alternatively, an input for connection of further pushbuttons can be provided. The neutral conductor N is looped through and forms, together with the switched phase  55 , the switching output. The signal  53  forms, together with the neutral conductor N, the output of the communications interface for controlling the loads. 
         [0031]      FIG. 5  illustrates the circuit arrangement of the power section of the apparatus according to the invention. A pushbutton T, which forms the signal  511 , is connected to the phase L. This signal is converted into a low-voltage signal  51  via a voltage divider  27  and an interference suppression stage  29  for further-processing in the control logic  21 . The first controlled switch  23 , which is in this case in the form of a relay, is arranged downstream of the pushbutton T. At the output of the switch  23 , the signal  55  is present in the form of a switching signal. A low-voltage signal for supplying the control logic is generated via a bridge rectifier and a step-down converter from the signal  55 . The control signal  53  for the communications interface is generated by a second switch  25  controlled by the control logic. 
         [0032]      FIG. 6  shows a schematic illustration of digital control logic  21  with a microcontroller  41  of the apparatus according to the invention. The microcontroller processes the input signal  51  and, independently of the input signal  51 , provides the two output signals  550  and  530  for driving the first and second control switch. The logic itself is implemented using the corresponding software. An overview of the basic functionality of the software is shown in  FIG. 11 . Essentially the states of the two relays  23  and  25  are interrogated and a distinction is drawn between a single depression of the pushbutton T and a “double click”. In the case of a single depression of the pushbutton, this signal is passed onto the second controlled switch  25  and output as signal  53  if the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  are switched on. Then, the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  are switched off by means of the first controlled switch  23 . If the loads are switched off, they are only switched on by means of the first controlled switch  23  and the signal with the switch-on pulse is then subsequently output as signal  53 . 
         [0033]    The expression “open/close relays  23 / 25 ” is in this case always intended to mean the output of a corresponding signal  550 / 530  at the output of the digital circuit. The driving of the first and second controlled switches is implemented via transistors  63  and  61 , respectively, and is illustrated in  FIGS. 8   a  and  8   b.  The control signals  530  and  550  are input into the transistors  61  and  63 , respectively, and said transistors then correspondingly switch the controlled switches  25  and  23 , respectively. 
         [0034]      FIG. 7   a  shows a schematic illustration of analog control logic  21 , which includes various logic gates and flip-flops. 
         [0035]    The associated state table for the logic is illustrated in  FIG. 7   b.  This table applies in principle also to digital control logic as shown in  FIG. 6 . The procedure for the analog control logic is as follows: the input signal  51  of the pushbutton is converted in a pulse shaping unit  211  to form a time-discrete pulse train, is then sampled in a detection unit  213  with respect to a single depression of the pushbutton and then the two control signals  530  and  550  are generated on the basis of this information in a logic switching unit  215 . 
         [0036]      FIG. 12  depicts an exemplary sequence of a few relevant signals. The figure shows the input signal  51  generated by the pushbutton T and the time-discrete signals a, b, c, d and e. As intermediate signal, the output signal a of the AND gate  710  is specified, as well as the signals f and g. Finally, the signals  530  and  550  are specified. 
         [0037]      FIG. 12  represents a time-discrete sequence of  62  cycles of the analog control logic with different exemplary depressions of the pushbutton. The cycle numbers are specified in the first column. The function “switch on” i.e. a single depression of the pushbutton, is indicated in cycle  1 - 8 . Cycle  9 - 18  shows, by way of example, the function “dimming”, i.e. a relatively long depression of the pushbutton by means of which the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  are dimmed. The function “double click” for storing the dimming level can be followed in cycles  19 - 27 . The subsequent switching-off of the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  is indicated in cycles  28 - 34 . The touch-dim functionality “switch on with immediate dimming”, i.e. a long depression of the pushbutton when the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  are switched off, can be followed in cycles  35 - 45 . Cycles  46 - 54  in turn describe the storing of the dimming level, i.e. a double depression of the pushbutton. Cycles  55 - 62  finally switch the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  off again. 
         [0038]    In this table, it is possible to follow how a “double click” is intercepted and passed on in signal  53 , while a single depression of the pushbutton results in the loads  1 . 1 ,  1 . 2 , . . . ,  1 . n  being switched on or off, the hardware-side switching-on or switching-off of the loads correspondingly taking place in advance or subsequently. 
         [0039]      FIG. 9  shows a variant of the second embodiment with the additional feature of an illuminated pushbutton which only illuminates if all of the loads are disconnected. For this purpose, a switching contact of the first controlled switch is used, which switching contact connects the pushbutton illumination L to the power supply if the loads are isolated from the power supply. 
         [0040]      FIG. 10  shows the installation described at the outset for controlling loads in accordance with the prior art. 
         [0041]    With the method according to the invention and the apparatus according to the invention it is possible to save a large amount of energy during operation of, for example, small to medium-sized lighting installations by virtue of the control gear and the apparatus according to the invention itself being isolated from the power supply system when the light-emitting means are disconnected. The control gear and the apparatus according to the invention are only connected to the power supply system again and then available with their full functionality if required. 
       LIST OF REFERENCE SYMBOLS 
       [0042]      1 . 1  . . .  1 . n  Loads  1  . . .  n    
         [0043]      21  Control logic 
         [0044]      211  Pulse shaping unit 
         [0045]      213  Detection unit 
         [0046]      215  Logic switching unit 
         [0047]      23  First controlled switch 
         [0048]      25  Second controlled switch 
         [0049]      27  Voltage divider 
         [0050]      29  Interference suppression circuit 
         [0051]      31  Apparatus according to the invention for controlling the power supply to electrical loads 
         [0052]      41  Microcontroller 
         [0053]      51  Low-voltage input switching signal 
         [0054]      511  Input switching signal 
         [0055]      53  Control signal for communications interface 
         [0056]      55  Switching signal for power supply 
         [0057]      530  Control signal for second controlled switch 
         [0058]      550  Control signal for first controlled switch 
         [0059]      61  Drive transistor for second controlled switch 
         [0060]      63  Drive transistor for first controlled switch 
         [0061]      710  AND gates 
         [0062]    T, T 1  . . . T n  Pushbutton for driving loads 
         [0063]    L Phase of power supply 
         [0064]    N Neutral conductor of power supply 
         [0065]    PE Ground of power supply 
         [0066]    V cc  Low-voltage supply of control logic 
         [0067]    GND Ground of control logic 
         [0068]    Clk Clock signal