DE1802070A1 - Monitoring device for the capacitor bank of a coupling filter of a ripple control transmission system - Google Patents
Monitoring device for the capacitor bank of a coupling filter of a ripple control transmission systemInfo
- Publication number
- DE1802070A1 DE1802070A1 DE19681802070 DE1802070A DE1802070A1 DE 1802070 A1 DE1802070 A1 DE 1802070A1 DE 19681802070 DE19681802070 DE 19681802070 DE 1802070 A DE1802070 A DE 1802070A DE 1802070 A1 DE1802070 A1 DE 1802070A1
- Authority
- DE
- Germany
- Prior art keywords
- monitoring device
- monitoring
- capacitor bank
- monitoring element
- capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/16—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for capacitors
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00006—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment
- H02J13/00007—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment using the power network as support for the transmission
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00032—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for
- H02J13/00036—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for the elements or equipment being or involving switches, relays or circuit breakers
- H02J13/0004—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for the elements or equipment being or involving switches, relays or circuit breakers involved in a protection system
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S40/00—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them
- Y04S40/12—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
- Y04S40/121—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment using the power network as support for the transmission
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Testing Electric Properties And Detecting Electric Faults (AREA)
- Protection Of Static Devices (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Description
Ueberwachungseinrichtung für die Kondensatorbatterie eines Ankopplungsfilters einer Rundsteuersendeanlage Die Erfindung betrifft eine Ueberwachungseinrichtung für die Kondensatorbatterie eines Ankopplungsfilters einer Rundeteuersendeanlage, mit einem Ueberwachungsglied zur Erzeugung eines Signals, das den Ausfall eines Kondensators der Kondensatorbatterie anzeigt.Monitoring device for the capacitor bank of a coupling filter of a ripple control transmission system The invention relates to a monitoring device for the capacitor bank of a coupling filter of a round control transmission system, with a monitoring element for generating a signal that the failure of a The capacitor of the capacitor bank.
In Kundsteuersendeanlagen wird mittels eines sogenannten Parallel-Ankopplungafllters einem Mittel- oder Hochspannungsverteilnetz ein xundsteuersignal überlagert. Dazu werden Kondensatorbatterien benötigt, die in der Regel aus der Reihen- und Parallelschaltung mehrerer Kondensatoren bestehen. Bei Durchschlägen von einzelnen Wickelpaketen derartiger*Hochspannungskondensatoren besteht die Gefahr, dass der Kondensatorkessel durch Gasentwicklung des Imprägniermittels aufbeult oder sogar platzt, wodurch grosser Schaden angerichtet werden kann.In customer control transmission systems, a so-called parallel coupling filter an xund control signal is superimposed on a medium or high voltage distribution network. In addition capacitor banks are required, which are usually made up of series and parallel connections consist of several capacitors. In the event of breakdowns of individual winding packages of such * high-voltage capacitors consists the danger that the condenser boiler due to gas evolution of the impregnation agent bulges or even bursts, which can cause great damage.
Zur Vermeidung von grösserem Schaden beim Ausfall eines Kondensators oder eines Wickelpaketes ist es bekannt, eine Einrichtung vorzusehen, die ein Alarmsignal auslöst oder die selbsttätige Abschaltung der Kondensatorbatterie vom Setz bewirkt, wenn der die Kondensatorbatterie durchfliessende Strom vom Sollwert abweicht.To avoid major damage in the event of a capacitor failure or a winding package, it is known to provide a device that generates an alarm signal triggers or causes the automatic shutdown of the capacitor battery from the setting, if the current flowing through the capacitor bank deviates from the setpoint.
Da dieser Sollwert spannungs- und frequenzabhängig ist, müssen besondere aufwendige Vorkehrungen zur Kompensation dieses Effektes getroffen werden.Since this setpoint is voltage and frequency dependent, special complex precautions are taken to compensate for this effect.
Als vorteilhafter haben sich Systeme erwiesen, bei welchen die relativen Aenderungen von Strom oder Spannung innerhalb der Kondensatorbatterien erfasst werden. Dazu ist es bekannt, die Kapazität jeder Phase in zwei möglichst gleich grosse, parallelgeschaltete Teilkapazitäten aufzuteilen und die in jedem Strang fliessenden Ströme miteinander zu vergleichen. Die Aenderung des Stromverhältnisses weist auf einen Kondensatördefekt hin und kann zur Betätigung der Abschaltung ausgewertet werden. Die Ansprechempfindlichkeit ist bei dieser Methode verhältnismässig gross.Systems have proven to be more advantageous in which the relative Changes in current or voltage within the capacitor banks are recorded. For this purpose, it is known to divide the capacity of each phase into two equally large, to divide parallel-connected partial capacities and those flowing in each strand Compare currents with each other. The change in the current ratio shows a condensate defect and can be evaluated to activate the shutdown will. The response sensitivity is relatively high with this method.
Nachteilig ist jedoch, insbesondere bei hohen Aetzspannungen,der grosse erforderliche Aufwand, denn fur jede Phase werden zwei Stromwandler benötigt.The disadvantage, however, is the large one, especially at high etching voltages required effort, because two current transformers are required for each phase.
Es ist ferner bekannt, die gesamte Kapazität in zwei in Stern geschaltete rlleilkapazitäten zu zu unterteilen und die Differenzspannung zwischen den beiden Sternpunkten zu überwachen. Bei einem Kondensatordefekt verschiebt sich der Sternpunkt der betreffenden Teilkapazität, und es tritt eine bifferenzspannung auf. nachteilig ist die geringere Empfindlichkeit. Ferner ist diese Methode bei einem Parallelankopplungsfilter, wo der Sternpunkt durch induktive Kopplungselemente gebildet wird, nicht anwendbar.It is also known to divide the entire capacitance into two star-connected intermediate capacitance to subdivide and the differential voltage between the two Monitor star points. In the event of a capacitor defect, the star point shifts of the relevant partial capacitance, and a differential voltage occurs. disadvantageous is the lower sensitivity. This method is also useful for a parallel coupling filter, not applicable where the star point is formed by inductive coupling elements.
Die Nachteile der bekannten Einrichtungen werden erfindungsgemäss dadurch behoben, dass das Beberwachungsglied in einem Diagonalzweig einer Brückenschaltung angeordnet ist, die von den Kondensatoren der Kondensatorbatterie gebildet wird.The disadvantages of the known devices are according to the invention fixed by placing the monitoring element in a diagonal branch of a bridge circuit is arranged, which is formed by the capacitors of the capacitor bank.
Nachfolgend werden einige Ausführungsbeispiele der Erfindung anhand der Leichnungen näher erläutert.Some exemplary embodiments of the invention are illustrated below of the corpse explained in more detail.
Es zeigen: Fig. 1 ein Prinzipschaltbild eines Parallelankopplungsfilters und Fig. 2 eine Ueberwachungeinrichtung.1 shows a basic circuit diagram of a parallel coupling filter and FIG. 2 shows a monitoring device.
In der Fig. 1 ist ein Prinzipschaltbild eines Parallelankopplungsfilters dargestellt, das Ausgangsklemmen 1, 2 und 3 eines in der Zeichnung nicht dargestellten dundsteuersenders mit den Phasenleitern , S und T eines Mittel- oder Hochspannungsverteilnetzes verbindet. talin Kopplungstransformator 4 besitzt in Stern geschaltete Niederspannungswicklungen 5, 6 und 7, die jeweils in Reihe mit einem Niederspannungskondensator 8, 9 oder 10 an die Klemmen 1, 2 und 3 angeschlossen sind. In Stern geschaltete Hochspannungswicklungen 11, 12 und 13 sind jeweils in Reihe mit einer Kondensatorbatterie 14, 15 oder 16 und einem Schalter 17, 18 oder 19 mit den Phasenleitern R, 5 und T verbunden.1 is a basic circuit diagram of a parallel coupling filter shown, the output terminals 1, 2 and 3 of a not shown in the drawing Dund control transmitter with the phase conductors, S and T of a medium or high voltage distribution network connects. Talin coupling transformer 4 has star-connected Low voltage windings 5, 6 and 7, each in series with a low voltage capacitor 8, 9 or 10 are connected to terminals 1, 2 and 3. High-voltage windings connected in star 11, 12 and 13 are each in series with a capacitor bank 14, 15 or 16 and a switch 17, 18 or 19 connected to the phase conductors R, 5 and T.
Jede der Kondensatobatterien 14, 15 und 16 besteht aus Mochspannungskondensatoren 20 bis 23, die eine Brückenschaltung bilden Eingangsklemmen 24 und 25 dieserBrückenschaltung stellen die Anschlüsse der Kondensatorbatterie dar. Ausgangsklemmen 26 und 27 eines Diagonalzweiges derselben sind an ein als Elektromagnet, beispielsweise als Zug- oder Stossmagnet ausgebildetes Ueberwachungsglied 28 angeschlossen. Von jedem der Elektromagnete 28 der Brückenschaltungen 14, 15 und 16 führt eine Wirkverbindung 29, deren besondere Ausgestaltung nicht näher dargestellt ist, zu den Schaltern 17, 18 und 19. Zum Schutz des Elektromagneten 28 vor unzulässig hohen Spannungen it demselben vorteilhaft eine Sättigungsdrossel 30 parallel geschaltet.Each of the capacitor batteries 14, 15 and 16 consists of high voltage capacitors 20 to 23, which form a bridge circuit, input terminals 24 and 25 of this bridge circuit represent the connections of the capacitor bank. Output terminals 26 and 27 of one Diagonal branches of the same are connected to an electromagnet, for example as a pull Monitoring element 28 embodied in the form of a shock magnet is connected. From each of the The electromagnet 28 of the bridge circuits 14, 15 and 16 has an operative connection 29, the particular configuration of which is not shown, to the switches 17, 18 and 19. To protect the electromagnet 28 from impermissibly high voltages It is advantageous if a saturation choke 30 is connected in parallel with the same.
Die beschriebene Einrichtung arbeitet wie folgt: Im normalen Betriebszustand befinden sich die Brückenschaltungen 14, 15 und 16 im Gleichgewicht, und die Elektromagnete 28 sind nicht erregt. Beim Ausfall eines der Kondensatoren 20 bis 23 oder eines einzelnen Wickelpaketes tritt zwischen den Ausgangsklemmen 26 und 27 eine Differenzspannung auf, und der Elektromagnet 28 der betreffenden Brückenschaltung spricht an. Ueber die Wirkverbindung 29 wird die selbsttätige Ausschaltung der Schalter 17, 18 und 19 bewirkt.The device described works as follows: In normal operating condition the bridge circuits 14, 15 and 16 are in equilibrium, and the electromagnets 28 are not aroused. If one of the capacitors 20 to 23 or one fails individual winding package occurs between the output terminals 26 and 27, a differential voltage on, and the electromagnet 28 of the bridge circuit in question responds. Above the operative connection 29 is the automatic deactivation of the switches 17, 18 and 19 causes.
Die Kondensatoren 20 bis 23, bei welchen es sich um Einzelelemente oder um Kondensatorgruppen, die aus mehreren Einzelelementen zusammengeschaltet sind, handeln kann, müssen selbstverständlich nicht gleiche Eapazitätswerte besitzen. Bedingung ist lediglich, dass die Brücke im normalen Betriebs zustand wenigstens annähernd abgeglichen ist.The capacitors 20 to 23, which are individual elements or groups of capacitors made up of several individual elements are able to act, need of course not have the same capacitance values. The only condition is that the bridge is at least in normal operating condition is approximately matched.
In der Fig 2 ist eine Ueberwachungseinrichtung dargestellt, die im wesentlichen aus dem Elek-bomagnet 28 und der Sättigungsdrossel 30 besteht, welche im Innern eines zylinderförmigen Hohlisolators 31 angeordnet sind. Anschlüsse 32 und 33 der parallelgeschalteten, auf einer Platte 34 montierten Elemente 28 und 30 sind am oberen Ende des nohlisolators 31 herausgeführt. DerElektromagnet28betätigt beim Ansprechen über ein Isoliergestänge 75 eine suecksilberwippe 36, welche auf einer schwenkbaren Halterung 37 befestigt ist.In Fig. 2, a monitoring device is shown, which in consists essentially of the elec-bomagnet 28 and the saturation choke 30, which are arranged inside a cylindrical hollow insulator 31. Connections 32 and 33 of the parallel-connected elements 28 and 28 mounted on a plate 34 30 are led out at the upper end of the noise isolator 31. The solenoid 28 is actuated when responding via an insulating rod 75 a mercury rocker 36, which on a pivotable bracket 37 is attached.
Anschlüsse 38 und 39 der Quecksilberwippe 36 sind aus dem Boden des Hohlisolators 31 herausgeführt.Connections 38 and 39 of the mercury rocker 36 are from the bottom of the Hollow insulator 31 led out.
Die anhand der Fig. 2 beschriebene Ueberwachungseinrichtung gestattet, von der hochspannungsseitigen Brückenspannung auf einfache Weise ein potentialfreies Signal abzuleiten, das zur Auslösung der Schalter 17, 18 und 19 herangezogen werden kann. Die Verwendung einer Quecksilberwippe gewährleistet eine einwandfreie Kontaktgabe.The monitoring device described with reference to FIG. 2 allows from the high-voltage bridge voltage in a simple manner a potential-free one Derive the signal that is used to trigger the switches 17, 18 and 19 can. The use of a mercury rocker ensures perfect contact.
Die beim Ausfall eines Kondensators an den Ausgangsklemmen 26 und 27 auftretende Brückenspannung kann selbstverständlich auch auf andere Weise in ein potentialfreies Signai umgeformt werden.The failure of a capacitor at the output terminals 26 and 27 occurring bridge voltage can of course also on other Way into a potential-free signal.
Grundsätzlich kann es sich beim Ueberwachungsglied 28 um ein hochohmiges oder um ein niederohmiges Element handeln. Ein hochohmiger Abschluss der Ausgangsklemmen 26 und 27 kann beispielsweise mittels eines Spannungswandlers erzielt werden. Beim niederohmigen Abschluss, beispielsweise-mittels eines Stromwandlers, stammt das Ausgangssignal aus einer Stromquelle, wobei der Strom durch die an die Ausgangsklemmen 26 und 27 angeschlossene Im pedanz bestimmt ist. Der niederohmige Fall ist im allgemeinen vorzuziehen, weil die beim Unterbruch einer Kondensatorverbindung auftretende Brückenspannung verhältnismässig klein bleibt und zudem keine Gefahr besteht, dass durch Sättigungserscheinungen Resonanzen auftreten können.In principle, the monitoring element 28 can be a high-resistance one or a low-resistance element. A high-resistance termination of the output terminals 26 and 27 can be achieved, for example, by means of a voltage converter. At the This comes from a low-resistance termination, for example by means of a current transformer Output signal from a current source, the current through which to the output terminals 26 and 27 connected impedance is determined. The low resistance case is in general preferable because the bridge voltage that occurs when a capacitor connection is interrupted remains relatively small and there is also no risk of saturation Resonances can occur.
Bei der Verwendung eines Stromwandlers kann auf die Sattigungsdrossel 30 verzichtet werden, wenn der Stromwandler selber Sättigungscharakteristik aufweist. Dies kann auf einfache Weise dadurch erzielt werden, dass der Stromwandler verhältnismässig hochohmig abgeschlossen wird.When using a current transformer, the saturation reactor can be used 30 can be omitted if the current transformer itself has saturation characteristics. This can be achieved in a simple manner in that the current transformer is relatively is terminated with high resistance.
Eine weitere vorteilhafte Ausführungsform besteht in der Verwendung eines Magnetventils als Ueberwachungsglied 28, das über einen Isolierschlauch hydraulisch oder pneumatisch einen Schaltkontakt betätigt. Ferner kann zwischen die Ausgangsklemmen 26 und 27 eine Lichtquelle geschaltet sein, die auf eine Fotozelle wirkt.Another advantageous embodiment consists in the use a solenoid valve as a monitoring element 28, which is hydraulically operated via an insulating hose or pneumatically actuated a switching contact. Furthermore, between the output terminals 26 and 27, a light source can be connected which acts on a photocell.
Claims (11)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1341268A CH470781A (en) | 1968-09-05 | 1968-09-05 | Monitoring device for the capacitor bank of a coupling filter of a ripple control transmission system |
Publications (3)
Publication Number | Publication Date |
---|---|
DE1802070A1 true DE1802070A1 (en) | 1970-04-30 |
DE1802070B2 DE1802070B2 (en) | 1975-03-27 |
DE1802070C3 DE1802070C3 (en) | 1975-11-06 |
Family
ID=4392190
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DE1802070A Expired DE1802070C3 (en) | 1968-09-05 | 1968-10-04 | Monitoring device for a capacitor battery |
Country Status (2)
Country | Link |
---|---|
CH (1) | CH470781A (en) |
DE (1) | DE1802070C3 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2903319C2 (en) * | 1979-01-29 | 1984-10-18 | Ero-Starkstrom Kondensatoren Gmbh, 8300 Landshut | Circuit arrangement for monitoring and / or displaying faults in an electrical power capacitor system |
DE3569640D1 (en) * | 1985-01-08 | 1989-05-24 | Bbc Brown Boveri & Cie | Filter circuit |
-
1968
- 1968-09-05 CH CH1341268A patent/CH470781A/en not_active IP Right Cessation
- 1968-10-04 DE DE1802070A patent/DE1802070C3/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
CH470781A (en) | 1969-03-31 |
DE1802070B2 (en) | 1975-03-27 |
DE1802070C3 (en) | 1975-11-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE2239654A1 (en) | DEVICE FOR DETECTING UNDERVOLTAGE IN MULTI-PHASE SYSTEMS | |
DE2436966A1 (en) | BAND FILTER | |
EP0131718A1 (en) | Device for detecting a short circuit in the winding of the rotor of an electric machine | |
DE2019184C3 (en) | Heavy current switchgear | |
DE1802070A1 (en) | Monitoring device for the capacitor bank of a coupling filter of a ripple control transmission system | |
EP0309753A1 (en) | Method for monitoring an inductive load | |
DE1613740A1 (en) | Monitoring circuit | |
DE3143622C2 (en) | ||
DE895945C (en) | Device for detecting earth faults | |
DE2516853A1 (en) | CONTROL DEVICE FOR MEASURING CIRCUITS FOR THE VOLTAGE ON POWER LINES | |
DE892146C (en) | Circuit arrangement for negative feedback amplifiers with a large frequency range | |
DE3511967A1 (en) | DEVICE FOR CONTROLLING ELECTRICAL CONSUMERS IN MOTOR VEHICLES | |
AT240948B (en) | Method and circuit arrangement for the selective detection of transient earth faults and permanent earth faults | |
DE3310558A1 (en) | Invertor having thyristors | |
AT267693B (en) | Arrangement for load switching in step transformers by means of controlled semiconductor rectifier devices | |
DE750691C (en) | High-pass filter for use in carrier-frequency messaging over wire networks | |
AT116983B (en) | Electrical locking device, in particular for preventing interference in electrical signal systems. | |
DE2115662A1 (en) | Device for discovering and displaying faults in an electrical direct current system of a vehicle | |
AT239327B (en) | Circuit arrangement to prevent double assignments | |
DE1175282B (en) | Circuit arrangement for testing lines in telecommunications, in particular telephone systems | |
DE2715331C2 (en) | Electronic switch | |
DE1938053C3 (en) | Method for AC parallel remote feeding of aerial cable systems | |
CH382904A (en) | Photoelectric flame monitoring device | |
DE1538297A1 (en) | Current-limiting network coupling | |
DE2253115A1 (en) | CIRCUIT ARRANGEMENT FOR DIRECTIONAL RECEPTION OF SIGNAL FREQUENCIES AND BLOCKING INTERFERENCE FREQUENCIES INCOMING OUTPUT |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C3 | Grant after two publication steps (3rd publication) | ||
E77 | Valid patent as to the heymanns-index 1977 |