Abstract: A drive lock includes a security control unit and an engine control unit that is ready for operation only when the engine control unit has received from the security control unit an encoded release code that matches a predetermined reference code. The engine control unit has storage devices into which it can enter a reference code. On receipt of a release code, it checks on whether a reference code is present in the storage devices. If there is a reference code matching the release code, the engine control unit makes itself ready for operation. If there is no reference code, it accepts the release code into the storage devices as the reference code.

Abstract: A vehicle security system includes a local area pager and additional anti-drive away protection. The remote transmitter of the system preferably includes a housing that is separated into two portions. A first portion is retained by the vehicle owner while a second portion is provided to a parking attendant with the vehicle. The vehicle owner can use the first portion to generate a signal that is received by the second portion and provides an indication to the parking attendant that the vehicle owner desires the attendant to retrieve the vehicle. Additionally, the system allows the vehicle owner to place the vehicle into a limited operation mode when the vehicle is left with the parking attendant.

Abstract: A key for a vehicle is provided with a transmitting circuit and an electric power receiving/signal transmitting circuit. The transmitting circuit transmits a wireless SW signal by radio waves in a case in which an instruction switch is on. The electric power receiving/signal transmitting circuit receives electric power from an electric power transmitting circuit provided in a key cylinder for a vehicle at a vehicle, and transmits a transponder code signal in a case in which the electric power receiving/signal transmitting circuit receives the electric power. When the key for a vehicle is inserted in the key cylinder for a vehicle, a light emitting device provided in the key cylinder for a vehicle emits light. In a case in which a receiver provided at the transmitting circuit receives the light, transmission of the wireless SW signal is prohibited.

Abstract: The system allows locating an enabling component of a motor vehicle. The enabling component, provided with a chip, is for example a smart card or an electronic key. The enabling component is addressed with a search signal from a transmitter fixed to the vehicle. The enabling component responds with an indicating signal. The indicating signal may be an audible signal emitted by the enabling component itself and/or the location information can be indicated by an indicator device fixed to the vehicle.

Abstract: A power-line filter for operation with a converter is provided having a regulated voltage source and sinusoidal phase currents, with the power-line filter helping to eliminate interference voltages particularly in the frequency range from 2 kHz to 150 kHz, which are normally not taken into account. The leakage currents to ground, in this context, can be minimized to the point that it is possible to operate the converter in an (AC/DC sensitive) Interference Filter (IF) protective circuit-breaker.

Abstract: A keyless entry device including a portable remote control for transmitting an operation signal in response to the reception of an interrogating signal and an onboard control module that is mounted on a vehicle.

Abstract: A device for limiting access to authorized users, for example, a vehicle access limiting device, includes a control device and a key device. The control device has memory wherein a preset user code and a preset secret code are stored. The key device has a transponder which includes a memory for storing the user code and the secret code transferred from the control device. The transponder emits the user code which has been encoded with the transferred secret code. The control device includes a comparison device which allows access only when the encoded user code emitted by the transponder agrees with preset information stored in the control device. The key device also includes a comparison device which prevents overwriting of the taught secret code unless it also receives the taught user code.

Abstract: The invention relates to an anti-theft method for a vehicle. In accordance with the invention, a code word (K1) chosen by the user, and the serial number ESN or IMEI of the telephone (K2) are stored in a fastener element (4) connected to the vehicle (5) and serving as a cradle for the portable telephone (1). Before starting, the user is to put his telephone in its place in the fastener element. The telephone automatically verifies whether its serial number ESN or IMEI is identical with the one that is stored in the fastener element. In that case, the starter means of the vehicle are unblocked so that the action of the ignition key makes a start possible. In the opposite case, the starter means remain blocked.

Abstract: A filter scheme for a battery power plant for supplying power to a load includes positive and negative voltage bus bars each having an input and an output, the output adapted to be connected to the load. A capacitor is connected between the bus bars adjacent to the output of power plant, and an inductor is connected to either one of the bus bars adjacent to the output of the power plant to reduce bus voltage transients.

Abstract: An engine start controlling device prevents an engine from starting with exchanged ECUs. In a non-volatile memory 20f of an engine control ECU 20, information regarding whether or not an immobilizer function is used is stored, while a judging unit 20e interprets signals from input terminals 40-1-40-n and judges whether or not an immobilizer function is available. Only when the signals from the input terminals 40-1-40-n show immobilizer function unavailableness does the ECU operate as an ECU without the immobilizer function.

Abstract: An apparatus and method for substantially reducing zero sequence harmonic currents at the load-end of branch circuits that supply single-phase, non-linear loads. The invention includes a three-phase, six-terminal, zig-zag autotransformer which functions as the zero sequence filter. The first winding, which is located on the first core leg, is connected in series with the sixth winding, which is located on the third core leg. The third winding, which is located on the second core leg, is connected in series with the second winding, which is located on the first core leg. The fifth winding, which is located on the third core leg, is connected in series with the forth winding, which is located on the second core leg. In this configuration, the first winding is magnetically coupled to the second winding, the third winding is magnetically coupled to the forth winding and the fifth winding is magnetically coupled to the sixth winding.

Abstract: Multiple pieces of equipment installed in a vehicle are freely installed and removed to equipment connection slots. A bus line interconnects the multiple pieces of electrical equipment installed in the equipment connection slots. Multiple operating switches arranged in a single unit on an operating section are provided in correspondence to the multiple pieces of electrical equipment for producing control signals to control each of the multiple pieces of electrical equipment. When any one of the operating switches is manipulated, a head unit controls, via the bus line, the electrical equipment corresponding to the manipulated operating switch.

Abstract: A communication system and method for keyless-entry alarms includes a vehicle-mounted alarm transducer (215) controlled by a vehicle-mounted control system (250) that includes a receiver (207). The system also includes a hand-held R.K.E. transmitter device (200) for transmitting a radio-frequency message. The vehicle-mounted alarm transducer (215) is deactivated when receiving the transmitted radio-frequency message. If the vehicle-mounted alarm transducer (215) was active when it was deactivated, and a deactivate-alarm command code is not received in the radio-frequency message, then the vehicle-mounted alarm transducer (215) is reactivated after the transmitted radio-frequency message is completely received and decoded.

Abstract: The present invention is a method and apparatus of providing EMI filtering through the implementation of a voltage sense circuit that is used in conjunction with a power correction circuit in an electromagnetic (EMI) filter system. The apparatus comprises a filter that receives an alternating current signal, where the filter has an input terminal and an output terminal. The apparatus also comprises a power correction circuit having a voltage reference input terminal and an output terminal. A voltage sense circuit having an input terminal is coupled to the input terminal of the filter. The voltage sense circuit has an output terminal that is coupled to the voltage input terminal.

Abstract: A system and method for controlling refuelling of a motor vehicle having an internal-combustion engine and having a control unit for a central locking system and several locking/unlocking devices (VEEs) for doors and covers which are controlled by the control unit. The locking and unlocking device of the filler inlet compartment cover can be switched by the control unit independently of the other locking and unlocking devices. When the filler neck cap and/or the filler inlet compartment cover is open, the internal-combustion engine cannot be started. When the internal-combustion engine is running, the filler inlet compartment cover cannot be unlocked.

Abstract: A page receiver system for disconnecting an electrical system from a power source and preventing manual reconnection of the electrical system to the power source. The page receiver security system includes a pager receiver connected between the electrical system and the power source. The pager receiver includes a receiver for receiving a page signal and a relay. A disable switch is connected between the relay and the electrical system. When installed in a vehicle, a hood open switch may be connected to the relay for opening and closing the hood of the vehicle. The page receiver security system is operable between a first mode in which a page signal is received by the receiver causing the relay to connect the electrical system to the power source thereby allowing the electrical system to operate and a second mode in which the disable switch is activated to trigger the relay, disconnecting the electrical system from the power source and preventing operation of the electrical system.

Abstract: An anti-vehicle-thief apparatus registers specific ID codes of a plurality of keys, and determines validity of a key, for example, in accordance with an operation of the key 1 including a transponder having one of the registered specific ID codes. The anti-vehicle-thief apparatus registers a code specific to the key and confirms an operation in which an ignition switch is turned on and off five times by using the key, where this operation is for changing the ID codes specific to the plurality of keys registered in EEPROMs. After the confirmation of the operation, ID codes specific to a plurality of new keys are successively registered, thereby preventing a third person from using the old keys, as well as making registration of the ID codes specific to the new keys easily.

Abstract: A system for regulating the voltage by switching capacitor banks and for preventing damage due to harmonic resonance in an AC power supply line after a capacitor bank is switched. The system includes a detector for detecting the harmonic distortion in the supply line, and multiple capacitor banks connected in parallel to the supply line. At least one switch is in series with each capacitor bank to connect or disconnect the capacitor bank to the supply line. A controller operates the switches and receives input from the detector. After a capacitor bank is switched to improve conditions in the supply line, the controller compares the total harmonic distortion to an action threshold and switches capacitor banks as programmed when the total harmonic distortion exceeds the action threshold for a predetermined period of time in order to avoid a resonant condition that could cause damage to equipment.

Abstract: A power conditioning circuit for conditioning power supplied by a power source at a nominal frequency over line, neutral and ground conductors includes first, second and third impedances coupled to the line, neutral and ground conductors, respectively, and to output lines. Each of the impedances prevents power at frequencies greater than the nominal frequency from reaching the output lines.

Abstract: The present invention teaches an integrated steering system for use with a directional control system and an electronic control system for controlling an engine and a first and a second feature. The integrated steering system comprises an integrated ignition system and a multifunction switch. The integrated ignition system comprises a lock having a key, an ignition, and a microcomputer for coupling the ignition with the electronic control system if the lock is enabled by the key, and for preventing the ignition from being coupled with the electronic control system if the lock is disabled by the key. Moreover, the multifunction switch is coupled with the microcomputer for enabling and disabling the first and second features such that the microcomputer controls the first and second features in response to the multifunction switch.

Abstract: An apparatus for essentially eliminating transmission line reflected waves and standing waves and for reducing common mode transient currents for use with a three phase motor controller, the apparatus including a common mode choke in series with a filter network between an inverter and a motor, the filter including three inductors and three resistors, the inductors and resistors together forming three inductor-resistor pairs, each pair including an inductor in parallel with a resistor, each pair linked to a separate one of three transmission supply lines which link the inverter to the motor, values of the resistors and inductors selected according to transmission line theory.

Abstract: An active harmonic filter selectively sources current to or draws current from power lines. The active harmonic filter includes a controller which executes a predictor routine which predicts the current to be supplied to or drawn from the power line at a time t+.DELTA.t to reduce load induced phase differences between the line voltage and the line current. An integrating slow control routine integrates difference currents between actual line currents and desired line currents in equivalent segments of time in different cycles of the power line. The integrated differences may be combined with proportionally controlled difference currents to reduce or eliminate harmonic line currents. A current balancing routine enables the active harmonic filter to balance currents in two or more lines of a polyphase power line. The predictor, integrating slow control and current balancing routines, may be used singly or in combination to improve the condition of line currents on the power lines.

Abstract: A low power transmitter for use in a vehicle security system includes an oscillator that is isolated from a transmitter antenna. An amplifier is coupled between the oscillator and the antenna to achieve the isolation. The amplifier and the isolator are tied to a single signal source so that each is initiated at the same time. The amplifier has a faster turn-on time than the oscillator so that the amplifier is fully operational at the instant it receives an output signal from the oscillator. The amplifier amplifies the single frequency of the oscillator and that amplified signal is transmitted by the antenna to a controller, which responsively controls the vehicle security system.

Abstract: An antitheft apparatus for a motor vehicle can allow operation of an internal combustion engine of a motor vehicle to be started notwithstanding of decision of discrepancy in an engine start enabling signal ascribable to transient error in communication between a code collating means and an engine start decision means. An identification code stored in an engine key (1) is read out upon every starting of operation of the motor vehicle to be collated with a preset identification code to thereby make decision as to whether or not both of the identification codes coincide with each other. Upon decision of coincidence, the identification code as read out is affixed with a rolling code which is updated every time the engine of the motor vehicle is operated, to thereby generate an engine start enabling signal. Means are provided for sending the engine start enabling signal and for generating the rolling code. The rolling code as generated is sent to the rolling code adding means (30b).

Abstract: Upon the occurrence of a predetermined event, the protection system will automatically disable the vehicle or object that the system is installed in. Several sensors and events can be monitored by the system simultaneously, and the system can be automatically or manually programmed to selectively intervene or monitor events as they occur. Radiolocation systems, such as GPS and TELETRAC(.TM.) are used to monitor status and send commands.

Abstract: An antitheft system for use in portable consumer electronic equipment. The antitheft system includes an antitheft receiver that receives a deactivation code that is transmitted by a paging system transmitted when the device is reported stolen. Upon receipt of the deactivation code, a microprocessor within the electronic equipment causes the equipment to become inoperative. To ensure the antitheft receiver is not removed or tampered with, the microprocessor queries the antitheft receiver for a unique identification number associated with the device.

Abstract: A locking bar may engage with an ignition switch which is switched to a START position and a LOCK position by a pushing operation, and may unlock a steering shaft when the ignition switch is at the START position and lock the steering shaft when the ignition switch is at the LOCK position. An ID code decision portion may decide whether or not an input identification number coincides with a registered identification number. A first actuator may unlock the ignition switch when the input identification number coincides with the registered identification number, and may lock the ignition switch when the input identification number does not coincide with the registered identification number. Accordingly, lock of the steering shaft due to failure or malfunction during running can be prevented.

Abstract: A system for limiting access to certain components of a vehicle where the vehicle has a valet mode wherein access to the certain components of the vehicle is limited and a normal mode wherein the certain components are operable. The vehicle has a processor programmed to place the vehicle in the valet mode upon receipt of a first signal and to place the vehicle in the normal mode up receipt of a second signal. Mode changing signals are transmitted to a processor using a remote control and a connector switch removably connected to the remote control, wherein the remote control transmits the first signal when the connector switch is disconnected from the remote control, and wherein the remote control transmits the second signal when the connector switch is reconnected to the remote control. A radio in the vehicle and/or a voice-recognition system can also be used to transmit the mode changing signals to the processor.

Abstract: An anti-theft system includes a strategy for providing secure communications between a system controller and a remote signaling device. A communications initiator allows the transfer of information or signals between the system controlling and the remote signaling device only under pre-defined conditions. The system controller preferably includes a transmitter portion for transmitting signals or information to the remote device and a receiver portion for receiving signals from the remote device. Similarly, the remote device preferably includes a transceiver so that two-way communication is accomplished between the controller and the remote signalling device.

Abstract: In a vehicle antitheft system having an immobilizer unit which reads in an identification code generated by and transmitted from an ignition key of the type having a built-in signal transmitter, an ID code of a first ignition key is tentatively stored in the immobilizer unit until different ID codes of first and second ignition keys are registered even in the event where ID code entry operation is interrupted before registration of the first and second keys' ID codes during an entry of the first ignition key ID code and is resumed with the second ignition key.

Abstract: A key for a vehicle has a push button, a first transmitter-receiver circuit for transmitting a first ID signal stored in a first memory in response to an ID request signal, and a second transmitter-receiver circuit for transmitting a second ID signal in response to a pressing operation of the push button. An in-car antitheft system has a check circuit for comparing the received first ID signal with a registered ID, and an engine control circuit for inhibiting the operation of an engine if the received ID does not correspond to the registered ID. When the button is pressed for a duration longer than a predetermined length, the second transmitter-receiver circuit of the key transmits the first ID signal in place of the first transmitter-receiver circuit.

Abstract: A system for disabling a speeding vehicle comprising a hand held code transmitter having a trigger to activate a output transmitter to send out a unique signal. A vehicle has an engine with an acceleration cable, a mechanism for disabling the engine when power is received, and a control module having a receiver. The control module is coupled to an antennae for receiving the unique signal. The control module is further coupled to a battery. The control module reacts to the unique signal and in turn responds with power to the mechanism for disabling the engine.

Abstract: A neutral conductor filter having three transformers. A first transformer has a primary winding connected to a first power conductor and the neutral conductor. A second transformer has a primary winding connected to a second power conductor and the neutral conductor. A third transformer has a primary winding connected to a third power conductor and the neutral conductor. The secondary windings of the transformers are connected in series with each other and a capacitor is connected in parallel with the series connected secondary windings. The capacitor is tuned with the leakage reactance of the transformers so that the impedance to zero-sequence third harmonic current is minimized.

Abstract: An engine start control apparatus, includes a code storing device which stores a plurality of normal codes which indicate a normal vehicle key belonging to a vehicle and a key corresponding to the normal vehicle key, and an immobilizer which determines as to whether an inherent code input form one of a signal input device and an inherent code input device is included in the normal codes stored in the code storing device, and on the basis of the results of determination, the immobilizer controls permitting/prohibiting the starting of the engine. Therefore, when the normal code of the plurality of normal codes and the input inherent code match, the immobilizer permits the starting of the engine.

Abstract: A hybrid active power filter having programmed impedance characteristics is presented. In accordance with which, a passive device comprising a capacitor C.sub.F is connected in series with an active device which are together connected in shunt with a power source and a load at transmission lines of a power system. Capacitor C.sub.F substantially supports the full-line voltage V.sub.H of the power source, whereby the active filter is exposed to a substantially lower voltage than the line voltage V.sub.H. The active device includes on active filter, i.e., an inverter current regulator with a programmable controller for executing a control algorithm. The controller of the active device receives signals corresponding to a voltage V.sub.M, at the low side of filter capacitor C.sub.F. Voltage V.sub.M is at a substantially lower voltage than the line voltage V.sub.H, whereby the cost of sensing voltage V.sub.M is significantly less than sensing the high line voltage V.sub..

Abstract: In an apparatus for control of controller equipment for damping power oscillations in a power line, the controller equipment is serially connected between a first connection point and a second connection point in the power line in an electric network for alternating current. The controller equipment is adapted to serially generate in the power line, dependent on a control order, a damping voltage for damping power oscillations in the power line. Controlling equipment receives sensed quantities of the power network and forms a phase deviation dependent on these quantities. The phase deviation is the difference between a phase angle of a first voltage at the first connection point and a phase angle of a second voltage at the second connection point. The controlling equipment forms the control order dependent on the time rate of change of a function of the phase deviation.

Abstract: An active interphase reactor for twelve-pulse diode rectifiers is disclosed. The system draws near sinusoidal currents from a power utility. In one embodiment, a low kVA (0.02 P.sub.o (PU)) active current source injects a triangular current into an interphase reactor of a twelve-pulse diode rectifier. This modification results in near sinusoidal utility input currents with less than 1% THD. In alternative embodiments, a low kVA, 12-pulse system with an autotransformer arrangement (kVA rating of 0.18 P.sub.o (PU)) is implemented with the proposed active interface reactor. The resulting systems draw clean power from the utility and are suitable for powering larger kVA ac motor drive systems.

Abstract: The present invention relates to protection circuit and method for the EMI/RFI suppression system (2) of such a five-conductor electrical system in which the neutral conductor (N) is provided with a bandstop-type filter circuit (2) for the suppression of a harmonic interference current component. According to the invention, on the neutral conductor (N) is placed a current transformer (CT) having over its secondary a resistive branch (R.sub.1), and in parallel therewith, a filter branch (5) comprising a bandpass filter (LC) tuned to the fundamental frequency of said neutral-conductor filter circuit (2) and said filter branch (5) having in series with said bandpass filter branch (LC) a switch element (4) suitable for short-circuiting said neutral-conductor filter circuit (2) when current in said filter branch (5) exceeds a preset upper limit level.

Abstract: In an anti-theft system for a motor vehicle, an oscillating circuit of a transceiver in the motor vehicle is modulated with code information of a portable transponder. A demodulator detects the code information and carries it onward to a computer unit, where it is checked for authorization. Component tolerance or temperature changes can mean that initially no code information will be demodulated, despite a properly functioning transponder. According to the invention, the frequency of the modulated oscillation is then measured and reregulated to a command frequency.

Abstract: A vehicle start-up permission device in which an identification code stored in an electronic key can be kept secret. A start-up permission ECU (1) is magnetically coupled with a transmit-receive controlling circuit (6) of an electronic key (3) via an antenna (2) and an antenna (5) of the electronic key (3) with the electronic key (3) being inserted in an ignition key (4) so as to supply electric power for the circuit. When the ignition switch (4) is operated to an ACC position, the start-up permission ECU (1) transmits a random number code. When the transmit-receive controlling circuit (6) of the electronic key (3) receives the random number code, it converts by predetermined encryption processing a previously registered key code to a return code on the basis of the random number code and returns the return code.

Abstract: The alternative power system provides microprocessor grade, filtered output power capable of replacing standard NiCad battery packs in portable electronic devices. The invention makes use of capacitor banks comprised of capacitors having different values, whereby the individual capacitors act as individual filters to substantially eliminate all transients which are present in the source of power, which is typically provided by rechargeable batteries on a host system, such as a forklift or hand truck.

Abstract: A method and apparatus is provided for restoring a sagging voltage signal on a power transmission line, caused by a remote fault in the utility power system, to a balanced three-phase condition at the pre-fault voltage level. Voltage restoration is provided by injecting a voltage signal in series with the power transmission line which restores the load voltage vectors to the pre-fault condition. The restored load voltage vectors are rotated by a selected phase angle such that zero real power flow is associated with the voltage restoration. The voltage compensation signal may be injected into the power transmission line by connecting a voltage compensator inverter in series with the transmission line. The voltage compensator inverter may be controlled to provide the desired injected voltage signal using a synchronous reference frame based controller.

Abstract: The invention relates to a method for protecting against unauthorized use of a vehicle which has bidirectional communication with a master station, whereby it is possible not only to transmit exclusively a position message of the vehicle to the master station or to transmit exclusively enabling signals to the vehicle from the master station, but also to make the communication appropriate to requirements. The necessary transmission of information is substantially reduced in that the enabling signal is broadcast only when requested by the vehicle. On the other hand, it is still not possible for the enabling to be carried out at the vehicle end only.

Abstract: A keyless motor vehicle starting system to replace a conventional ignition lock and ignition key of a motor vehicle. The system comprises a portable wireless transmitter and a receiver/controller board which is installed deeply inside the motor vehicle behind a steering column cover or cluster cover of the motor vehicle. The portable wireless transmitter has a transmitter integrated-circuit chip loaded with a computer program to implement a process to generate a power-code and a starter-code and controls the states of a motor vehicle by sending a radio-frequency-modulated power-code and starter code. The receiver/controller board has a receiver integrated-circuit chip loaded with a computer program to implement a process to detect the power-code and the starter-code and control a plurality of switches for switching among the OFF, ACC, START and RUN states of a motor vehicle.

Abstract: The invention provides a key/vehicle communication device in which an electronic key capable of being inserted into a steering-column lock controls activation of an immobilizing device having an inductive key/steering-column lock communication channel for recognizing whether a key authorized for use is inserted. A key/vehicle communication channel is also provided, for the remotely controllable activation of at least one vehicle-side function via a key-side actuating member. A vehicle-side control unit determines, via the inductive key/steering-column lock communication channel, whether a key authorizing the driving of a vehicle is inserted in the steering-column lock and, if so, blocks the vehicle-side part of the key/vehicle communication channel.

Abstract: A ground voltage reduction device is connected between a neutral reference node and a ground node defined by two bypass capacitors of a blocking circuit. The ground voltage reduction device senses the voltage difference between the neutral reference node and the ground node and drives the ground node to reduce the voltage difference between a voltage of the ground node and a voltage of the neutral reference node.

Abstract: A battery powered electro-mechanical lock and method of actuating it under normal battery voltage level condition an access variation arrangement enables the lock to be opened upon the single entry of a correct access code and under low battery voltage levels conditions another access variation arrangements, which prevents the lock from being opened unless the user enters the correct access code N number of times, where N is between 2 and 24.

Abstract: A passive filter device for a capacitor in series with a substantially inductive transmission line of an electric transmission system is disclosed. The passive filter device comprises a double-loop RCL filter in parallel with the series capacitor. At power frequency, the filter device allows the power frequency current to pass through the series capacitor with minimum power losses. At sub-synchronous resonance frequencies, the passive filter device provides bypassing of the series capacitor with maximum selectivity of the RCL filter.

Abstract: A key for storing a predetermined electronic code is provided independently from a vehicle, and a mechanism is provided for comparing the electronic code in the key with a built-in stored electronic code after an ignition switch is switched from an OFF position to an ON position. When the electronic codes do not correspond, the vehicle is prevented from starting, and it is prevented from starting even when the electronic codes do correspond if the number of non-correspondences reaches a predetermined value. In this way, the vehicle is prevented from starting when the electronic codes match by chance when unauthorized start-ups are attempted.

Abstract: A device for improving the quality of audio and/or video signals comprises a main electrical circuit comprising an integrated circuit arranged for producing an output pulse signal having a predetermined frequency, and a toroidal inductor having a magnetic core which has a central opening and which is surrounded by a conducting wire, said toroidal inductor being arranged to be powered by said output signal.The device is arranged between a power supply unit and a signal processing unit which is connected by at least a phase- and a neutral conductor to said power supply unit such that said conductors pass through said central opening of said magnetic core, said toroidal inductor creating an alternating magnetic field within its core when it is powered by said output signal, so that said magnetic field induces an electric field which acts on said conductors.