KR100612150B1 - Device for individual control of multiple circuit-units using single cable - Google Patents

Abstract

The present invention relates to a device for individually controlling a plurality of circuit units connected along one cable, comprising a central device, a cable from the central device, and a band pass filter connected in parallel to the cable and having different frequency bands. It is characterized by consisting of a plurality of circuit units. If the carrier selects the carrier frequency from the central unit and sends the control signal through the cable, the signal does not pass through the band pass filter of the circuit unit that does not match the frequency, so that it does not affect other circuit units. Only it is delivered to control its circuit unit.

Description

Device for individual control of multiple circuit-units using single cable

1 is a configuration diagram of an individual control device of several circuit units through a conventional cable

2 is a block diagram of an individual control device of several circuit units through a single cable according to the present invention

3 is a diagram showing a band pass filter circuit and its frequency characteristics included in the present invention.

4 is a diagram showing a band pass filter circuit including a detector and its frequency characteristics;

5 is a diagram for explaining a method of improving channel density using a competitive connection method.

6 is a double resonance and triple resonance circuit diagram

7 is a schematic diagram of an interphone and its circuit diagram according to another embodiment of the present invention.

8A is a diagram illustrating a method of superimposing a frequency signal from a central apparatus on a power line, FIG. 8B is a method of turning home appliances on and off at a central apparatus, and FIG. 8C is a diagram illustrating a method of utilizing existing household appliances for home automation.

9 is a configuration diagram and a circuit diagram of a temperature measuring system according to another embodiment of the present invention.

10 is a view for explaining a signal receiving method using a solenoid switch

<Explanation of symbols for the main parts of the drawings>

10: central unit 20: cable

22: frequency signal output line 24: ground line

30: circuit unit 40: repeater

50: band pass filter 60: speaker

70: switch portion 120: return line

140: power line 160: solenoid switch unit

180: thermistor 190: sensor

The present invention relates to an individual control device for a plurality of circuit units via a single cable, in particular, each circuit unit includes a band pass filter (hereinafter referred to as 'BPF') and the central unit selects a specific frequency and transmits a control signal, The present invention relates to an individual control device of several circuit units through a single cable that controls only selected circuit units without affecting other circuit units that do not fit.

Typically, the individual control device of several circuit units via cables is a device for controlling a plurality of installed circuit units in a central unit, which is connected via a cable with each circuit unit. Hereinafter, with reference to the accompanying drawings will be described in more detail with respect to the individual control device of the various circuit units via the cable.

Figure 1a is a block diagram of an individual control device of several circuit units through a conventional cable.

The control device includes a central device 10, a plurality of circuit units 30, and a cable 20. Conventionally, as shown in FIG. 1, a central device is used to individually control several circuit units 30. In (10), the cable 20 was connected to each circuit unit 30 like an octopus foot. Therefore, when controlling a large number of circuit units 30 there is a problem that the cables 20 are tangled or confused with each other and difficult to handle because of the volume and weight of the bundle of cables 20.

In addition, the cost of purchasing the cable 20 is proportional to the number N of the circuit units 30, but the design, construction, maintenance, and maintenance costs are proportional to the square of N since the cables 20 are easily entangled with each other or confusing which one. Increasingly, when controlling a large number of circuit units 30 was expensive.

Figure 1b is a block diagram of an individual control device of several circuit units developed to solve this problem.

Referring to FIG. 1B, the control device individually controls each circuit unit 30 using a single cable 20 through the digital repeater 40. At this time, each repeater 40 has a unique address and communicates digitally with the central device 10 to exchange information. Although this method solves some of the above problems, there is a problem that the cost is large and occupies a lot of volume because N expensive instruments 40 are required.

The present invention is to solve the above problems, an object of the present invention is to selectively control each circuit unit by connecting a plurality of circuit units having a band pass filter having a different frequency band in parallel along the cable coming from the central unit It is to provide an individual control device of several circuit units through a single cable.

In order to achieve the above object, an individual control device for a plurality of circuit units through a single cable according to the present invention includes a central device for transmitting frequency signals of different frequency channels, and a plurality of circuits including band pass filters having different frequency bands. And a cable connected to the unit, the central unit and the plurality of circuit units to transmit frequency signals from the central unit to the plurality of circuit units.

The band pass filter may include a voltage threshold circuit. The voltage threshold circuit may include a diode unit in which at least one forward diode and at least one reverse diode are connected in parallel.

The band pass filter may include a detector for detecting the AM signal when the signal passing through the band pass filter is an AM signal, wherein the detector includes at least one diode. The diode acts as a voltage threshold circuit for giving a voltage threshold to the band pass filter.

The cable may include a frequency signal output line for outputting a frequency signal, a ground line, and a return line through which a frequency channel having a high voltage is transmitted among the frequency channels, and the cable is connected to an existing power line to supply power through a power line. And a frequency signal is transmitted. When the cable is connected to the power line, it may be characterized in that a switch unit for controlling the central unit in the middle of the power line.

In addition, the central unit may be characterized by delivering a signal to one of the circuit units at once by dividing a time by one channel in transmitting frequency signals of different frequency channels to the circuit unit. And overlapping the frequency signals of several channels to deliver signals to the plurality of circuit units at once (overlapping delivery).

In addition, the central unit transmits only one frequency value as a frequency signal for transmitting to a predetermined circuit unit, and only when the frequency value matches the frequency band of the band pass filter of the corresponding circuit unit. A frequency signal is transmitted using a single resonance for transmitting a frequency signal, or two or more frequency values are transmitted as specific frequency signals for transmission to a predetermined circuit unit, and the two or more frequency values correspond to a predetermined frequency signal. Only when the frequency bands of the band pass filter of the circuit unit coincide with each other, the frequency signal is transmitted using multiple resonances for transmitting the frequency signal to the circuit unit.

On the other hand, the individual control unit of the various circuit unit through a single cable according to the present invention includes a central device for transmitting a frequency signal of different frequency channels and receiving a signal from the circuit unit, a band pass filter having different frequency bands A plurality of circuit units, selectively connected to the central unit and the plurality of circuit units, for receiving a frequency signal and transmitting signal information related to a load included in the circuit unit to the central unit; And a cable for transmitting frequency signals and signal information from the circuit unit to the central device.

In this case, the cable comprises a frequency signal output line for outputting a frequency signal transmitted from the central unit to the circuit unit, a ground line, and at least one signal line for transmitting signal information from the circuit unit to the central unit. The circuit unit is characterized in that it comprises a four probe method circuit. At this time, the circuit unit may be characterized in that it comprises a switch.

In addition, the central unit transmits only one frequency value as a frequency signal for transmitting to a predetermined circuit unit, and the circuit unit only when the frequency value matches the frequency band of the band pass filter of the corresponding circuit unit. A frequency signal is transmitted using a single resonance to transmit a frequency signal, or two or more frequency values are transmitted as a specific frequency signal for transmission to a predetermined circuit unit, and the two or more frequency values correspond to a predetermined circuit unit. It is characterized in that the frequency signal is transmitted using multiple resonances for transmitting the frequency signal to the circuit unit only when the frequency bands of the band pass filter coincide with each other.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Incidentally, in the drawings of the present invention, the same reference numerals as those in the related art will be used for the same configuration as the conventional art.

As shown in FIG. 2, the present invention includes a circuit unit 30 equipped with a central device 10, a cable 20, and a band pass filter 50. The plurality of circuit units 30 are connected in parallel by several circuit units from the cable 20 coming from the central unit 10, such as Christmas decorative bulbs.

The cable 20 includes two or more conductive wires insulated from each other, one of which is a frequency signal output line (not shown), and the other of which is a ground line (not shown). Depending on the conditions of use, it is also possible to prune two or several branches along the way or arrange them like a net.

Hereinafter, the present invention configured as described above will be described in detail the operation of controlling several circuit units individually through a single cable.

First, in order to send a frequency signal to each circuit unit 30 from the central unit 10, the central unit 10 is connected with a cable 20 consisting of two conductive wires, such as a coaxial cable or a power line. Several circuit units 30 are connected to the cable 20 in parallel, and pass through the band pass filter 50 before being connected to the circuit units.

In addition, when the frequency band of the band pass filter 50 installed at the inlet of each circuit unit 30 is different from each other, and the signal is transmitted at one frequency from the central apparatus 10, the signal transmits energy to another circuit unit 30. Without passing through), only the band pass filter 50 corresponding to the frequency passes through and the circuit unit 30 is operated or controlled. Since the central unit 10 determines which of the plurality of circuit units 30 transmits a frequency signal to a specific circuit unit 30, each circuit unit 30 may be classified as an allocated frequency channel.

On the other hand, there are two methods for delivering a signal: in-line delivery and overlapping delivery. In-line delivery is a method of delivering a signal to a required channel by dividing the time one channel at a time, and in the overlapping delivery, a plurality of frequency signals are cabled (20). Superimposed on the multiple circuit units 30 simultaneously and independently. Overlap delivery is more efficient in terms of signal delivery than in-line delivery, but since overlapping delivery requires multiple frequency oscillators in the central unit, which method is better depends on the application. In the individual control device for the multiple circuit units through a single cable of the present invention, one of the above two methods of serial delivery and overlapping delivery can be selected and applied according to the situation.

In addition, as a signal sent to the designated circuit unit 30, a digital signal for turning the signal on / off may be used, but an audio signal or a video signal may be transmitted through amplitude modulation or frequency modulation. It is also possible to carry analog signals.

FIG. 3A illustrates a band pass filter circuit included in an exemplary embodiment of the present invention, FIG. 3B illustrates a band pass filter circuit having a voltage threshold, and FIG. 3C illustrates frequency characteristics thereof.

3A is an impedance matched LC resonant circuit, and since the LC resonant circuit operates as a band pass filter, it is already known. Using such a circuit is easy to implement because of the low cost and simple circuit. However, this resonance circuit does not have a good frequency characteristic as the band pass filter 50, so the curve does not drop quickly at both ends of the band. In other words, the frequency characteristics of the bandpass filter 50 do not sufficiently fall outside the intended band, resulting in incomplete separation between adjacent channels.

Therefore, even when the band pass filter 50 having a poor frequency characteristic is used, a technique is required in which the carrier frequency operates only the intended channel and does not affect other channels at all. In the present invention, the band pass filter 50 is required. Immediately after, a signal below a certain value including a voltage threshold circuit is cut out.

Figure 3b is a circuit to which this method is applied and Figure 3b proposes a diode voltage threshold as a simple amplitude filter. When the current flows in the forward direction of the diode, there is a voltage drop of a specific value (about 0.6 V per unit) in the diode, so the voltage threshold value (hereinafter, 'Vth') can be set by selecting the number of diodes. In addition, in order not to drop the Q value in the LC resonant circuit of FIG. Can be.

FIG. 3C shows the frequency characteristics of each filter shown in FIGS. 3A and 3B. In the case of FIG. 3B, the signal decreases by Vth while the signal passes through the diode, but shows good blocking outside the intended frequency range. Therefore, it can be usefully used.

On the other hand, when the circuit unit receives the AM signal, the frequency signal passing through the band pass filter 50 should be detected. FIG. 4A shows a band pass filter circuit including a detector, and FIG. 4B shows frequency characteristics of the circuit shown in FIG. 4A.

Referring to FIG. 4A, the circuit includes a detector 100 including a diode and a capacitor. At this time, in the case of using the circuit of FIG. However, the inter-channel frequency interval of Δf or more is inefficient in terms of channel density. Therefore, a method for improving channel density should be sought. Hereinafter, channel density improvement using a competitive connection method and channel density improvement using dual resonance will be described.

5 is a view for explaining a method for improving channel density using a competitive connection method, FIG. 5A is a cable 20, FIG. 5B is a circuit diagram to which a competitive connection method is applied, and FIG. 5C is a circuit diagram of FIG. 5B. Frequency characteristics are shown.

In the case of an AM signal, as shown in FIG. 5A, a return line 120 is added to the cable 20 in addition to the frequency signal output line 22 and the ground line 24. The circuit of FIG. 5B is configured including the three lines. Since the diode D ₂ in the circuit of FIG. 5B prevents reverse current from flowing, only a current flows in D ₂ of a circuit unit having the highest detected voltage among several channels, and a reverse voltage is applied in D2 of another channel so that no current flows at all. . That is, the channel having the highest voltage in competition between the channels monopolizes the return line 120.

In Fig. 5C, the frequency characteristic of the LC resonance circuit of each circuit unit and the current flowing in R _t through the competition between the channels having this frequency characteristic are shown. Referring to FIG. 5C, channel 1 monopolizes the return line 120 in the frequency band FB1 and channel 2 monopolizes the return line 120 in the frequency band FB2. In comparison with Δf in FIG. 4B, the frequency interval between channels is Δf. Even if it is much smaller than that, it can be seen that frequencies are well isolated and frequency bands are exclusively divided. Therefore, this method can be usefully used to increase the channel density, and using this method makes it possible to install three times more channels in a given frequency band than otherwise.

If it is possible to install N channels in a given frequency band using single resonance in the case of using the competitive connection method described above, N (N-1) using double resonance shown in FIG. 6A is used. ) Channels can be installed. In the case of N = 100, N (N-1) = 9900 can be called a breakthrough. When two frequencies are superimposed via the frequency signal output line 22, the output voltage of the circuit unit in which the two frequencies f1 and f2 of the double resonance are both matched is surely higher than the output voltage of the circuit unit in which only one frequency is met or none is matched. Therefore, it will occupy the return line 120. 6B shows a circuit using triple resonance, in which a signal of three frequencies is superimposed, and in this case, the number of possible channels is N (N-1) (N-2). In this way, the double or triple resonance method makes it possible to install a large number of channels in a given frequency band.

FIG. 7A is a block diagram of an interphone to which individual control devices of various circuit units are applied through a single cable of the present invention, and FIG. 7B is a circuit diagram of the interphone block diagram shown in FIG. 7A.

As shown in FIG. 7A, the control device of the present invention connects a plurality of speakers 60 with a central device 10 and a cable 20 so that sound is transmitted to only one of the speakers 60 installed in different places. Be sure to In the circuit of FIG. 7B, a portion consisting of C ₁ , C ₂ , and L is an impedance matched resonance circuit, and diodes (D) and C ₃ supply the detected voice signal to the speaker 60.

In this case, the line-delivery method can deliver sound to only one speaker at a time, and the overlap-delivery method can deliver independent signals to several speakers at the same time. As the load indicated by R in FIG. 7B, not only a speaker but also a light bulb, a neon sign, an LED, a solenoid switch, an electric motor, and the like can be used. For example, by using a solenoid switch in the R position Home automation is a technology that turns on and off various home appliances from a central unit, and home appliances that are turned on and off by solenoid switches include heating switches, electric kettles, washing machines, lamps, electric windows, and electric blinds. In addition, when using this technology, it is possible to utilize an existing power line without installing a signal transmission cable in a house. On the other hand, in the present invention, the solenoid as a switch operation is only one embodiment, any of which can be used as long as the switching operation is possible.

8A illustrates a method of superimposing a frequency signal from the central apparatus 10 on a power line, FIG. 8B illustrates a method of turning home appliances on and off in the central apparatus 10, and FIG. 8C illustrates a method of utilizing existing household appliances for home automation. Is shown.

As shown in FIG. 8A, the frequency signal cables 22 and 24 from the central unit 10 are connected to their power lines 140 through a 60 Hz high pass filter (HPF). At this time, since the signal frequency is in the kHz region, the signal is supplied to the existing power line 140 through the wall outlet. When the home appliance is connected to the power line 140 wherever the home appliance is located, the signal frequency is supplied together with the power along the code.

As shown in FIG. 8B, the frequency signal supplied to the power line of the home appliance to be turned on and off in the central unit may be used to operate the solenoid switch 160. Specifically, according to the method shown in FIG. 8B, since 60 Hz is filtered by the band pass filter (BPF) 50, from the two terminals of the power line without a separate high pass filter (HPF). The frequency signal is supplied, and the signal passing through the band pass filter 50 operates the solenoid switch 160 through inspection. This allows the energy of the frequency signal to be used for solenoid operation without a separate power supply. If the home appliance is too large and the solenoid is heavy and it is difficult to directly operate the solenoid only by the power of the frequency signal, the solenoid may be driven with a separate DC power supply as usual. In addition, in order to prevent the frequency signal supplied by the power line from one house operating the home appliances of the neighboring house, a low pass filter (LPF) is attached to the main power line to block the frequency signal.

The home automation technology employing the control device of the present invention is that existing home appliances can be simply utilized for home automation as shown in Fig. 8C: the solenoid switch 162 controlled by the central unit 10 is inexpensive and Make it small so that you can plug in your home appliances' power lines. In addition, since the frequency of the frequency signal is lower than that of the digital signal, there is less attenuation when the signal is transmitted over the power line.

Figure 9 is another embodiment of the present invention, Figure 9a is a block diagram of the individual measurement device of the various circuit units through a single cable of the present invention applied to the temperature measurement system, Figure 9b is a view of the temperature measurement system shown in Figure 9a It is a circuit diagram.

The temperature measuring system can be used for fire monitoring, gas pipe leak monitoring, power plant steam valve gasket leak monitoring, etc. by monitoring the temperature distribution in real time. The temperature measuring system designates one circuit unit 30 at the central unit 10, and a cable 20 made up of four conductors as shown in FIG. 9A to receive a signal from the designated circuit unit 30. Used. Each of the four conductive wires is composed of a frequency signal output line 22, a ground line 24, a signal 1 line 26, and a signal 2 line 28. The switch unit 70 includes data of a circuit unit designated by the central unit. Connect only signals to signal lines exclusively.

FIG. 9B is a circuit diagram according to an embodiment of the temperature measuring system shown in FIG. 9A, which simultaneously shows an embodiment of the competitive connection method shown in FIG. 5B. As shown in the figure, when the frequency signal inputted through the band pass filter 50 is sensed by the galvanometer unit 100, C3 acts as a DC power source so that a current flows through a voltage divider consisting of Rx and Rs. . The total voltage V1 is measured at the central unit 10 via the signal 1 line 26 and the divided voltage V2 is via the signal 2 line 28. At this time, even if the central device 10 supplies the frequency signal with a stable output, the signal attenuates on the way, so that the total voltage V1 changes. However, if V1 and V2 are measured at the same time, since the value of the standard resistance Rs is determined, the resistance value Rx of the thermistor 180 can be calculated. In addition, when the input impedance of the resistance meter is increased, almost no current flows in the signal 1 line 26 and the signal 2 line 28, so that an accurate value can be measured without a voltage drop.

In the circuit of 9b, diodes D ₁ and D ₂ are attached to all circuit units and are provided to isolate other circuit units from the operation of the selected circuit unit. Due to these two diodes, the two signal 1 line 26 and the signal 2 line 28 are used exclusively by the selected circuit unit, and the reverse voltage is applied to D ₁ and D ₂ of all other circuit units so that the signal is cut off. However, the signals V ₁ and V ₂ pass through the diodes D ₁ and D ₂ respectively, but the potential of the signal drops to some extent, but this is not a problem because it can be reflected in the calculation.

Since diodes D ₁ and D ₂ competitively connect a channel to a signal line, it can be seen that the above-described channel density improvement principle is automatically applied. It is also possible to use the above-mentioned double resonance or triple resonance method in the temperature measurement system.

10 illustrates a signal reception method using a solenoid switch.

As shown in FIG. 10, a method of simply switching a signal of a sensor to a signal line using a signal passing through the band pass filter 50 and the detector 100 is used. In FIG. 10, three signal lines are applied, and a signal 1 line 26, a signal 2 line 28, and a signal 3 line 29 are illustrated. At this time, since the solenoid is operated by the serial delivery signal, the number of sensors from which the signal connected to the signal line comes from can be clearly classified and processed in the central apparatus 10.

The signal collection method using the solenoid switch is used to measure the temperature of various parts in trains, ships, airplanes, automobiles, etc. It can be conveniently used when a passenger needs to manage a central unit, such as a switch calling passengers.

As described above, the individual control unit of the various circuit units via a single cable according to the present invention has a different frequency band prior to being connected to the circuit unit, rather than the central unit and the various circuit units are directly connected to the cable. By passing through the band pass filter, the central unit has an effect of controlling the circuit unit by selectively connecting each circuit unit with a different frequency channel.

Claims (20)

A central apparatus for transmitting frequency signals of different frequency channels; A plurality of circuit units having band pass filters having different frequency bands; And a cable connected to the central unit and the plurality of circuit units to transmit a frequency signal from the central unit to the plurality of circuit units, wherein the cable outputs a frequency signal, a frequency signal output line, a ground line, and a frequency channel. Individual control device for multiple circuit units through a single cable, characterized in that the return line is transmitted to the frequency channel with a high voltage. The method of claim 1, wherein the band pass filter, Individual control device for multiple circuit units via a single cable, characterized in that it comprises a voltage threshold circuit. The method of claim 2, wherein the voltage threshold circuit, And at least one forward diode and at least one reverse diode comprising a diode portion connected in parallel. The method of claim 1, wherein the band pass filter, And a galvanizing unit for detecting the AM signal when the signal passing through the band pass filter is an AM signal. The method of claim 4, wherein the inspection unit, And at least one diode, said diode acting as a voltage threshold circuit for giving a voltage threshold to said band pass filter. delete The method of claim 1, wherein the central device, Individual control device for a circuit unit via a single cable, characterized in that for transmitting the frequency signals of different frequency channels by one channel divided time to deliver the signal to one of the circuit unit at a time. The method of claim 1, wherein the central device, Individual control device for a circuit unit via a single cable, characterized in that for transmitting the frequency signal of the different frequency channel overlapping the frequency signal of several channels to deliver the signal to the plurality of circuit units at once. The method according to any one of claims 1 to 5, 7 and 8, The cable is connected to an existing power line, the individual control device of the various circuit units through a single cable, characterized in that the power and frequency signals are transmitted through the power line. The method of claim 9, When the cable is connected to the power line, the control unit of the individual circuit unit through a single cable, characterized in that the switch unit for controlling the central unit in the middle of the power line. The method according to any one of claims 1 to 5, 7, and 8, wherein the central device is As a frequency signal for transmitting to a predetermined circuit unit, only one frequency value is transmitted and the frequency signal is transmitted to the circuit unit only when the frequency value matches the frequency band of the band pass filter of the corresponding circuit unit. Individual control of several circuit units via a single cable, characterized in that the resonance transmits the frequency signal. 10. The apparatus of claim 9, wherein the central unit is As a frequency signal for transmitting to a predetermined circuit unit, only one frequency value is transmitted and the frequency signal is transmitted to the circuit unit only when the frequency value matches the frequency band of the band pass filter of the corresponding circuit unit. Individual control of several circuit units via a single cable, characterized in that the resonance transmits the frequency signal. The method according to any one of claims 1 to 5, 7, and 8, wherein the central device is It transmits two or more frequency values as a specific frequency signal for transmission to a predetermined circuit unit, and only if the two or more frequency values coincide with the frequency band of the band pass filter of the corresponding circuit unit. Individual control device for multiple circuit units over a single cable, characterized in that for transmitting the frequency signal using multiple resonances for transmitting the frequency signal. 10. The apparatus of claim 9, wherein the central unit is It transmits two or more frequency values as a specific frequency signal for transmission to a predetermined circuit unit, and only if the two or more frequency values coincide with the frequency band of the band pass filter of the corresponding circuit unit. Individual control device for multiple circuit units over a single cable, characterized in that for transmitting the frequency signal using multiple resonances for transmitting the frequency signal. A central apparatus for transmitting frequency signals of different frequency channels and receiving signals from circuit units; A plurality of circuit units including band pass filters having different frequency bands to selectively receive frequency signals, and transmit signal information related to loads included in the circuit units to the central apparatus; And a cable connected with the central unit and the plurality of circuit units to transmit frequency signals and signal information from the central unit to the plurality of circuit units or from the circuit unit to the central unit, wherein the cable is connected to the central unit. A plurality of circuit units via a single cable, characterized in that consisting of a frequency signal output line, a ground line for outputting a frequency signal transmitted to the circuit unit, at least one signal line for transmitting signal information from the circuit unit to the central unit Individual controls. delete The method of claim 15, The signal line is implemented in two, and a current flows through a voltage divider in which a unknown resistor and a standard resistor are connected in series in a circuit unit, and then the total voltage and the divided voltage are applied to the two signal lines. Individual control of multiple circuit units via a single cable, characterized in that the central and centralized voltages can be measured. The method of claim 15, The circuit unit is a separate control device of the multiple circuit unit via a single cable, characterized in that it comprises a switch. 19. The apparatus of claim 15, 17 or 18, wherein the central device is As a frequency signal for transmitting to a predetermined circuit unit, only one frequency value is transmitted and the frequency signal is transmitted to the circuit unit only when the frequency value matches the frequency band of the band pass filter of the corresponding circuit unit. Individual control of several circuit units via a single cable, characterized in that the resonance transmits the frequency signal. 19. The apparatus of claim 15, 17 or 18, wherein the central device is It transmits two or more frequency values as a specific frequency signal for transmission to a predetermined circuit unit, and only if the two or more frequency values coincide with the frequency band of the band pass filter of the corresponding circuit unit. Individual control device for multiple circuit units over a single cable, characterized in that for transmitting the frequency signal using multiple resonances for transmitting the frequency signal.

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