DE1233752B - Transmission device for a network overlay consumption reporting system - Google Patents

Description

Transmitting device for a network overlay consumption reporting system Used to fundamentally simplify the process of identifying a public utility company Amount of electricity, gas, water, heat and others supplied to individual buyers consumer goods distributed via long-distance lines, a repentant technique was developed, which assigns a sensor to each consumption meter individually or in groups, which issues reports on the consumption recorded locally by the consumption meter, which are transmitted to a central control point via a telecommunication channel. When the telecommunication channel is superimposed on a supply network for electrical energy is, one speaks of a network overlay consumption reporting system.

Some knowledge can now be found in the development of such systems utilize which the field of ripple control technology has produced without However, it is possible to easily apply the features of known ripple control systems transferring new technology; because with network overlay consumption reporting systems must Signals with great reliability from the numerous endpoints of a power distribution network be fed to a central point, which collects the incoming information and forwards it for evaluation. In particular, it is difficult to use for reasons Very simply structured transducers signals of this kind in terms of economy to generate and superimpose an alternating current network that this at a remote Location in the frequency spectrum of the network can be identified with certainty.

Known network overlay consumption reporting systems use them as measuring transducers a transmitting device, which by periodically switching on an electrical oscillating circuit an audio frequency voltage in the form of compensating oscillations to the alternating current network to be superimposed generated, which causes audio frequency currents that propagate throughout the network complex and a part of which also reaches a specially coordinated recipient, the recognizes these audio frequency currents as signals from the transmitter and uses them as consumption reports assigned to a specific consumption meter. Switching on the electrical oscillating circuit in the transmission device is known to take place by cam-controlled pushbutton contacts or by so-called resonance oscillators.

The consumption meters connected to a consumption reporting system have a changeover switch with two changeover contacts. After each measurement one the switch position of this switch is determined by the The consumption meter counter changed. In known circuit arrangements depends the type of audio frequency signal generated by the transmitting device from the switching position of the switch. This creates an image of this switch position in the receiver, to which a defined information content is assigned in a certain time allocation.

The new technology of the network overlay consumption reporting systems provides As is known, the task that all parts work extremely reliably and that in particular the transmission equipment with a very simple structure and completely maintenance-free at least must achieve the same service life as conventional consumption meters own. The fulfillment of all these requirements causes considerable difficulties, especially the achievement of the desired simplicity, given the very large Ultimately, the number of transmitters to be installed in supply networks about the possibility of extensive practical use of such consumption reporting systems .decides. On the other hand, a good solution to the task at hand promises one not insignificant profit for the entire economy.

It has now been recognized that the previously proposed transmission devices, although they work very reliably, some of them are still undesirable in practice require great effort that but by a meaningful summary decisive simplifications of measures, some of which are also known from other technologies are to be achieved, so that the demands made are now fully met can be.

Accordingly, the invention relates to a transmission device for a network overlay consumption reporting system for remote transmission of consumption information through a low-voltage distribution network for electrical energy superimposed signals that are generated by periodically switching on a electrical series resonant circuit to the network to be superimposed by means of a the AC mains voltage energized pushbutton switch with a pushbutton contact periodically actuating oscillating switching element are generated, the information content by the position of a switch each of a consumption meter is determined and the be carried on in the network against the direction of flow of the network energy. The invention is characterized in that the electrically in series with the series resonant circuit lying pushbutton contact of the pushbutton switch a charge-reversing diode is connected in parallel and that in the excitation circuit of the pushbutton switch a synchronous selector and over this one changeover switch for each consumption meter is arranged in series.

Embodiments of the transmission device defined here are explained below with reference to the drawing figures. It shows F i g. 1 a circuit diagram, F i g. 2 is a block diagram and FIG. 3 shows a circuit detail.

In FIG. 1, 1 denotes a phase conductor and 2 denotes a neutral conductor of a supply network for electrical energy, for example the single-phase house connection line of a 50 Hz three-phase low-voltage network of the public power supply, hereinafter referred to as network 3 for short. The phase conductor 1 and the neutral conductor 2 can, compared to the one shown in FIG. 1 selected representation can also be interchanged.

A power consumer 4 is connected to the network 3 via a consumption meter 5 which contains a measuring mechanism 6 and a counter 7 as well as a changeover switch 8 actuated by the counter 7 with a switching arm 9 and two changeover contacts 10 and 11. The switching arm 9 of the switch 8 is in direct electrical connection with the phase conductor 1. To connect the consumption meter 5, clamps arranged in a clamp piece 12 are used, which are shown in FIG. 1 are not designated further. On the other hand, in order to preserve the overlooked in FIG. 1 the terminal piece 12 are graphically divided. A section 13 therefore generally forms a structural unit with the clamping piece 12.

Numerous supply networks for electrical energy are already equipped with ripple control systems, so that a ripple control receiver 14 is usually assigned to a consumption meter or usually a group of the same, be it for tariff switching, for switching electrical heating devices or for interrupting certain consumer circuits at peak load. The ripple control receiver 14 connected to the network 3 has z. B. three command switches 15, 16, 17, the first two of which, 15 and 16, are connected in a known and therefore not shown manner with the consumption meter 6 and / or other consumption meters and other remote-controlled devices. The third command switch 17 is used to switch on a transmitter 18, which is attached to the installation panel of a house connection together with the consumption meter 5 and the ripple control receiver 14 and which must therefore comply with the official standards and regulations in form and design. This also applies in particular to a terminal strip 19, which for the sake of clarity in FIG. 1 was again divided and which, together with sections 20 and 21, usually forms a single component.

The main component of the transmitting device is a circuit 22, shown in the figure with wide lines, which contains, in series connection, an electrical series resonant circuit 25 consisting of a capacitor 23 and an oscillating circuit coil 24 and a pushbutton contact 26 of a pushbutton switch 27 . The pushbutton contact 26 is actuated by a vibrating switching element 28 , for the excitation of which an excitation winding 29 is used, one end of which is connected to the neutral conductor 2 of the network 3 via a phase shifter 32, which usually consists of a resistor 30 and a capacitor 31. A charge-reversal diode 33 is connected in parallel to the push button contact 26. An RC element 34, consisting of a resistor 35 and a capacitor 36, is also electrically parallel to the push button contact 26 and to the charge reversal diode 33.

The transmitting device 18 also contains a synchronous selector 37 with a selector contact 38 and a rotary selector 39, for the drive of which a synchronous motor 40 with a self-holding contact 41 is used. The command switch 17 of the ripple control receiver 14 is connected in parallel to the self-holding contact 41. A dash-dotted line 42 running in the figure from the synchronous motor 40 to the synchronous selector 37 indicates a transmission.

The second winding end of the field winding 29 of the push button switch 27 is connected to a sliding track 43 of the rotary selector 39 via the selection contact 38, that of a selector arm 44 in sequence with selector segments 45 of the rotary selector 39 is connected.

Two adjacent of choice segments 45 are each via a separate conduit 46 and 47 with one of the switching contacts 10 and 11 of the consumption meter 5 in electrical communication. In the same way, further consumption meters equipped with switches can be connected to further pairs of the selection segments 45.

The transmission device described so far works as follows: If the central control point wishes to receive consumption reports, it sends a corresponding ripple control command, which causes the command switch 17 in the ripple control receiver 14 to close briefly. The synchronous motor 40 then starts in the transmitting device 18 and maintains voltage via the self-holding contact 41 for a full selection period. A selection period expediently consists of several revolutions of the rotary selector 39, the selection contact 38 being actuated only during a single revolution. In a voting period, therefore, numerous - z. B. four hundred - recorded consumption meters, each of which is assigned a transmitter device individually or in groups. A division step of the rotary selector 39 is, for. B. 3 seconds, the dwell time of his selection arm 44 on each of the election segments 45 a little more than 2 seconds. During a single revolution of the rotary selector 39 within a selection period, the selection contact 38 always closes for a period of time which is slightly shorter than the dwell time when the selection arm 44 has hit one of the selection segments 45, so that the selection arm 44 always without current passes from one of the elective segments 45 to the next.

If the selector arm 44 of the rotary selector 39 now encounters one of the selector segments 45, which is connected via the line 46 to the changeover contact 10 of the changeover switch 8 in the consumption meter 5, then, if the switch arm 9 of the changeover switch 8 is currently on the changeover contact 10 , at Closing the selection contact 38 closes the excitation circuit of the pushbutton switch 27 and consequently excites the switching element 28 to oscillate, which results in a periodic closing and opening of the pushbutton contact 26. Each time the pushbutton contact 26 closes, the series resonant circuit 25 is connected to the mains voltage, the resulting charging current surges damped resonance vibrations of the audio frequency of z. B. 575 Hz or 425 Hz, stimulate tuned series resonant circuit, which, as is known, cause audio frequency currents in the network.

To now the detuning of the series resonant circuit by the To keep the network load constantly changing network impedance small, it is advisable to keep the The impedance of the series resonant circuit should be chosen to be significantly greater than the largest network impedance measured at the transmission locations, at least fifty times as great. One Such a dimensioning is only possible if it succeeds over the series oscillation circle 25 to achieve the highest possible voltage at the time of its connection, so an audio frequency current of sufficient strength is created. To achieve this, on the one hand the closing of the pushbutton contact 26 with the aid of the phase shifter 32, which per se can be designed as desired, as precisely as possible in time with the occurrence of a Peak value of the alternating mains voltage brought into agreement. Unfavorable transfer conditions It has also proven to be particularly useful to obtain the natural frequency of the switching element 28 of the push button switch 27 to subharmonic resonance to the mains frequency to be tuned, preferably to 25 Hz, if necessary also to 16 = /, or 121/2 Hz, so So that the time of closing of the pushbutton contact 26 always with homologous peak values the AC mains voltage, e.g. B. with positive peak values, is coincident.

To achieve the highest possible and largely constant On the other hand, the switch-on voltage across the series resonant circuit 25 is primarily the arrangement of the charge-reversal diode 33 which, if the polarity is correct, the capacitor 23 independently of its state of charge at the time of opening of the pushbutton contact 26 in each case the network voltage peak value opposite, z. B. charges negative polarity, while the push button contact 26 is open.

With the chosen arrangement, the RC element 34 can have a double effect unfold; it protects the charge-reversal diode 33 from harmful surge voltages and at the same time serves to quench the spark at the pushbutton contact 26.

A big advantage over the transmission device discussed here known similar devices is achieved in addition to the 33 with the help of the charge transfer diode significant increase and constancy of the transmission energy with simultaneous insensitivity of the transmitter against mains impedance fluctuations, the division of the transmitter circuits such that in the heavily loaded circuit 22 an interruption only by the Touch contact 26 takes place during the sensitive and with only a very small contact pressure working changeover switch 8 in the consumption meter 5 as well as the contact system of the synchronous selector 37 only lead the very small excitation current for the push button switch 27, what a Significant simplification and refinement of the components made possible light.

As already stated, one division of the rotary selector is d. H. thus one selection step of the synchronous selector 37, 3 seconds. The consumption meter 5-and of course every other consumption meter connected to the transmitter - is therefore a reporting time of two times 3 seconds is allocated, with only one an audio frequency signal is generated in the two 3-second intervals. Due to the Synchronous selection process can thus be used for each individual consumption meter at the receiving location of the signals recognize in which switch position the respective changeover switch 8 is located. From a comparison with that of the same consumption meter in a previous one Dialing period received message can be determined whether the counter 7 the changeover switch 8 has meanwhile been allocated and consequently the consumption of a certain amount of a consumer good measured or not. This determination serves as a basis for the utility company for consumption billing. Depending on the determination of the consumption amount, after their Measurement of the changeover contact 8 pass from one position to the other the consumption reports can be monthly, weekly, daily or hourly can be retrieved. According to preliminary calculations, the conditions are optimal in the case of daily one-off retrieval, if not only the resolving power of the consumption calculation, but also the service life of the transmission equipment is taken into account.

In FIG. 2 is now an example of the grouping in a block diagram which on the basis of FIG. 1 shown devices. In FIG. 2 means in analogy to FIG. 1 the reference number 3 the network to which the consumption meter 5, the transmitter 18 and the ripple control receiver 14 are connected. For example, on the installation board of a four-family house are now the consumption meter 5, three further household consumption meters 48, 49 and 50 as well a consumption meter 51 for house lighting and a consumption meter 52 for a Washing device or a heating system. All consumption meters mentioned here are included the transmitting device 18 attached to the same installation board. The ripple control receiver is also located on this installation panel 14. For example, a neighboring house has two consumption meters 53, 54 and a transmitter 55, while a workshop is also adjacent just a single consumption meter 56 owns. For the single family home and the workshop is not intended to have its own ripple control receiver.

It is now possible in many cases by appropriate summary neighboring consumption meters and transmission devices to a high utilization of the Devices required for the consumption report as well as the ripple control receiver to get. The problem arises that a larger number of double lines must be relocated. The main difficulty, however, is the limited capacity the usual terminal pieces or terminal strips on the devices, which are due to the official Standards and regulations for high-voltage devices are not designed to be space-saving at will can be; on the other hand, the space on installation boards is usually extremely high limited, so that the use of larger device housings, which also have a larger Allow number of clamps to be attached is out of the question, quite apart from the fact that that this is also forbidden for reasons of standardization and economy. One These problems are now solved in an advantageous further development of the previously described one Surprising setup by using the economy circuit known from electronics, as they are the F i g. 3 shows.

In FIG. 3 one recognizes the one already described with reference to FIG Excitation winding 29 of the push button switch 27 and also the selection contact 38 of the synchronous selector 37 and the counter 7 with the switch 8, the switch arm 9 and the switch contacts 10 and 11 owns. In FIG. 3, three cable runs 57, 58 and 59 are only partially drawn, of which the line 57 leads to the neutral conductor 2 of the network 3, if necessary via a phase shifter, as shown in FIG. 1 can be seen while the cable runs 58 and 59 are directly connected to the phase conductor 1 of the network 3. A dash-dotted one Line 60 in FIG. 3 indicates that the one in the figure is to the left of this line 60 drawn parts in the transmitting device 18, those shown to the right of it are located in the consumption meter 5.

The synchronous selector 37 has in the embodiment according to FIG. 3 a slightly modified rotary selector 61, the two sliding tracks 62 and 63 as well has two selector arms 64 and 65, which by means of an electrically non-conductive connecting web 66 connected to a common drive shaft, not shown in more detail in the figure are. The rotary selector 61 in turn contains selection segments 45, each of which -das first, third, fifth, etc. directly connected to the line 58 in electrical connection stand, while each of the remaining elective segments has a single line wire 67 to one changeover switch 8 of a consumption meter, e.g. B. 5, is performed, namely from a connection point 68 via a diode 69 to the changeover contact 10 and via a diode 70 polarized opposite to the diode 69 around the changeover contact 11.

The circuit arrangement is made on the synchronous selector 37. that the selection contact 38 via a capacitor 71 and a circuit point 72 and from this on the one hand via a diode 73 with the sliding track 62 and on the other hand via a diode 74 polarized opposite to the diode 73 is connected to the sliding track 63 is.

Is the switching arm 9 of the switch 8 on the changeover contact 10, it can be seen in the drawing when the dial contact 38 is closed Polarity of the diodes 69 and 74 and position of the selector arms 64 and 65 a charging current of the Capacitor 71 flow from the line 57 to the line 59, also a charging current in the opposite direction from the line 58 via the diode 73 to the line 57, so that the excitation winding 29 is permeated by alternating current and somil the pushbutton switch 27 is excited. However, if the switching arm 9 of the changeover switch 8 is on the changeover contact 11, the current path 57-67-59 is blocked by the opposite polarity of the diodes 74 and 70; consequently, the capacitor 71 can only be charged once via the one-way current path 58 to 57 take place, with the excitation winding 29 carrying no alternating current and the push button switch 27 thus remains de-energized. When switching the rotary selector 61 they are reversed here by a division step, that is to say by one of the selection segments 45 explained relationships with respect to the switching position of the switch 8 to. Man recognizes that by the from the F i g. 3 apparent advantageous arrangement the Switching position of the switch 8 with only a single line wire 67 between Consumption meter 5 and transmitter 18 in the same way on the push button switch 27 can be brought into effect, as shown on the basis of FIGS. 1 using of two lines 46 and 47 has been described, but this can be used in given number of terminals of the devices now twice as many consumption meters on one Connect the transmitting device. and at the same time in the terminal piece 12 of the consumption meter 5 one clamping element less is required.

To simplify the rotary selector 61, it is possible to use this like the Rotary selector 39 (FIG. 1) to be equipped with only one sliding track 62 (or 63) and the on the selection segments 45 resting conductive contact surfaces of in this case Selector arms 64 and 65 made of non-conductive material each have one for another diode of opposite polarity, both of which are attached to the selector arms and which replace the diodes 73 and 74, with the one on the single sliding track, z. B. 62, adjacent, here common sliding contact of the selector arms 64 and 65 to connect while the sliding track 6? connected directly to the capacitor 71 will.

If, as under FIG. 1 described in the E_ exciter circuit of the Pushbutton switch 27 a phase shifter with a series capacitor is provided, the capacitor 71 (FIG. 3) can of course be combined with the phase shift capacitor (31 in FIG. 1; be identical. The additional expense for the economy circuit according to FIG F i g. 3 is therefore insignificant compared to the essential technical installation Advantages of using this economy circuit in the present context To expand the connection options in front of consumption meters the transmission device described can be the excitation circuit for the pushbutton switch 27 also with low voltage of z. B. 2-1 full operations. To that end is Provide a network transformer in the transmission device 18 an additional line in front of this mains transformer to the switching arm 9 of the switch 8 required in consumption meter 5. Be. Use of the economy circuit according to F i g. This again results in a two-wire connection from the Sending device to each consumption meter, but can be a according to the regulations for low voltage trained part of the terminal block 19 substantially more terminals included than when rated for heavy current. In addition, all diodes of the economy circuit can (Fig. 3) be designed for low voltage, which results in cost savings, which by far compensate for the cost of the additional network transformer. A Another advantage of supplying the excitation circuit of the pushbutton switch 27 with low voltage lies in the considerable increase in the service life of everyone in this excitation circuit arranged contacts.

In summary, it can now easily be seen how through a meaningful and by no means obvious joining together of some of the known structures and circuit-related measures are essential in a novel context Advances could be made which opened the field to a new branch of technology for practical application on a large scale.

Claims (15)

Claims: 1. Transmitting device for a network overlay consumption reporting system for remote transmission of consumption information through a low-voltage distribution network for electrical energy superimposed signals that are generated by periodically switching on a electrical series resonant circuit to the network to be superimposed by means of a the AC mains voltage energized pushbutton switch with a pushbutton contact periodically actuating oscillating switching element are generated, whose information content is provided by the position of a switch each of a consumption meter is determined and the are forwarded in the network against the direction of flow of the network energy, characterized in that that the pushbutton contact lying electrically in series with the series resonant circuit (25) (26) of the push button switch (27) a charge-reversing diode (33) is connected in parallel and that in the excitation circuit of the push button switch (27) a synchronous selector (37) and via this one changeover switch (8) of each consumption meter (5) arranged in series is. 2. Sending device according to claim 1, characterized in that the parallel connection of the pushbutton contact (26) of the pushbutton switch (27) with the recharging diode (33) is an RC element (34) is connected electrically in parallel. 3. Transmitting device according to claim 1 or 2, characterized in that a phase shifter in the excitation circuit of the push button switch (27) (32) is arranged. 4. Transmitting device according to claim 1, characterized in that that each changeover switch (8) is assigned two contact segments (45) of the synchronous selector (37) are, each of which has its own line (46; 47) with one of the switching contacts (10; 11) of the switch (8) is connected. 5. Transmitting device according to claim 1, characterized in that the synchronous selector (37) using an economy circuit (F i g. 3) with the two changeover contacts (10; 11) each with a changeover switch (8) each via a single line wire (67) connected is. 6. Send device after Claim 1, characterized in that the natural frequency of the switching element (28) is tuned to subharmonic resonance to the frequency of the AC mains voltage. 7. Transmitting device according to claim 6, characterized in that at a line frequency of 50 IIz the natural frequency of the switching element (28) is 25 Hz. B. Sending facility according to claims 1 and 3, characterized in that the time of closing of the push button contact (26) of the push button switch (27) with homologous peak values of the AC mains voltage is coincident. 9. Transmitting device according to claims 1, 2, 3 and 8, characterized in that that the series resonant circuit (25) is one in relation to the greatest impedance of the low-voltage network (3) has a large impedance, preferably at least fifty times greater. 10. Transmitting device according to Claims 1 and 7, characterized in that the series resonant circuit (25) is tuned to a resonance frequency of 575 Hz. 11. Send device after Claims 1 and 7, characterized in that; that the series resonant circuit (25) a resonance frequency of 425 Hz is tuned. 12. Transmitting device according to claim 1, characterized in that a plurality of consumption meters (5, 48 to 54, 56) are connected to this. 13. Transmitting device according to Claims 1 and 5, characterized in that a rotary selector (61) of the synchronous selector (37) has two selector arms (64; 65) made of non-conductive material, the conductive contact surfaces of which lie on selector segments (45) and are polarized opposite to the other Diodes, both of which are attached to the selector arms, are electrically connected to a common sliding contact resting on a single sliding track. 14. Transmitting device according to claims 3 and 5, characterized in that a capacitor (31) of the phase shifter (32) with a capacitor (71) of the economy circuit is identical. 15. Transmitting device according to claim 1 or one of claims 4, 5, 12, 13 and 14, characterized in that for feeding the excitation circuit of the push button switch (27) is used for low voltage. Considered publications: German Patent No. 966 060; "Funk und Ton", No. 6, 1954, p. 323.