Abstract: A position indicator includes a tubular core member, a first coil, a second coil, a substantially bar-like rod, a pen-pressure detecting element, at least one capacitor, and a switch. The tubular core member is formed by a substantially bar-like first magnetic core and a substantially bar-like second magnetic core, which are combined in a transversal direction thereof to form a through-hole therebetween. At least one of the first and second magnetic cores may include a recessed portion formed therein extending in the axial direction thereof. The first coil is wound around the tubular core member, and the second coil is wound around the second magnetic core. The rod is inserted into the through-hole of the tubular core member. The pen-pressure detecting element detects a pressure applied to an end of the rod (i.e., the pen tip). The capacitor is connected to the first coil to form a resonant circuit.

Abstract: A non-contact sensor system is provided that comprises a first sensor element disposed on an outside surface of a chamber. The chamber comprises an inside surface configured to receive a piston, and the piston is configured to move a value X within the chamber without physically contacting the first sensor element. The non-contact sensor system further comprises a second sensor element disposed on the piston and separated from the first sensor element by a wall of the chamber. The first sensor element and the second sensor element are operatively coupled to facilitate sensing the value X. The non-contact sensor system may be configured to sense velocity, acceleration, volume, and other values.

Abstract: A non-contact sensor system is provided that comprises a first sensor element disposed on a stationary member, and a second sensor element disposed on a rotational member. The second sensor element is proximate the first sensor element without physically contacting the first sensor element. The rotational member is configured to facilitate selection of at least a first position and a second position, and the first sensor element and the second sensor element are operatively coupled to facilitate sensing of the selected position.

Abstract: A magnetic passive position sensor including a base plate and a cover which form a housing, a magnet that can be moved outside the housing, a resistance network that has several individual electric contacts, and a plurality of contact spring elements that are arranged within the range of motion of the magnet, are interconnected by a common base, and consist of a bending zone and a contact zone. The contact spring elements face the contacts of the resistance network in such a way that the contact zones can be moved from the magnets against the contacts of the resistance network, the contact zones of at least two contact spring elements being assigned to each individual contact of the resistance network. Two adjoining contact spring elements are mechanically interconnected.

Abstract: The present invention relates to a proximity sensor having a first transmission coil, a second transmission coil, at least one reception coil, an excitation device which is connected to the first and second transmission coils, and an evaluation unit which is connected to at least one transmission coil and/or to the excitation device as well as to the at least one reception coil.

Abstract: In order to facilitate the assembly of an elongated magnetostrictive sensor in an enveloping tight protective profile, the sensor unit according to the invention comprises a head piece which closes the face of the protective profile and which partially reaches into the protective profile, wherein the wave conductor unit and also the circuit board are initially connected form locked with the head piece and electrically connected therewith.

Abstract: A non-contact sensor system is provided that comprises a first sensor element and a rotary member disposed proximate the first sensor element without physically contacting the first sensor element. The rotary member may be configured to be rotated about an axis Y by a shaft configured to pass through the rotary member along the axis Y at a value X. The non-contact sensor system further comprises a second sensor element disposed on the rotary member proximate the first sensor element without physically contacting the first sensor element, and the first sensor element and the second sensor element may be operatively coupled to facilitate sensing the value X.

Abstract: An electromechanical transducer device for a vehicle transmission or drive has a lever (1) that can be pivotally actuated about at least one first axis (2a, 2b) and which is mechanically decoupled from the transmission or drive. The lever is supported by a suspension (3) on the first axis (2a, 2b). The axis (2a, 2b) comprises at least one first component (6a, 6b) of a magnetic rotational angle sensor system (6a, 6b, 7a, 7b) at an axial end section to detect angular position or rotational movement of the lever (1). A second component (7a, 7b) of the rotational angle sensor system is arranged on the suspension (3) opposite of the end section of the axis (2a, 2b), wherein the axial end section is located within the suspension (3). A circuit board (15) accommodating the rotational angle sensors (7a, 7b) is arranged on the suspension (3), and the circuit board (15) comprises at least one flange-like extension (17, 18) protruding from the circuit board plane.

Abstract: In a method according to the invention to determine the relative position (?) of a resolver, an exciter winding is excited with a reference signal, a first signal resulting from the reference signal in a first winding is sampled and a second signal resulting from the reference signal in a second winding is sampled, an uncompensated Fourier coefficient for the first signal is determined and an uncompensated Fourier coefficient for the second signal is determined. A compensated Fourier coefficient for the first signal and a compensated Fourier coefficient for the second signal is determined and the relative position of the resolver is determined from the compensated Fourier coefficients. The compensated Fourier coefficients essentially compensate the change of the uncompensated Fourier coefficients due to the phase shift of the resolver and/or the change of the relative position during the sampling.

Abstract: A sensor assembly for sensing a movable object which, in one embodiment, includes a housing defining an interior cavity. A rotor is retained in the cavity. The rotor defines a central bore and a magnet is mounted in an off-center pocket defined by the rotor. The rotor is coupled to the shaft of the movable object whose position is to be measured. A sensor is also retained in the cavity in a relationship at least partially overlying the magnet and adapted to sense at least the direction of the magnetic field generated by the magnet to generate an electrical signal indicative of the position of the movable object. In another embodiment, the rotor and sensor are mounted in separate interior housing cavities separated by an interior housing wall.

Abstract: A magnetic encoder scale comprises a series of periodically spaced magnetic marks. A reference mark is applied to the scale using an applicator or template, which has a feature for locating the reference mark. The applicator or template comprises one or more magnetic marks corresponding to the periodic scale marks, whereby the applicator or template automatically assumes a defined phase relationship relative to the periodic scale marks when placed on the scale. The reference mark may be attached to the scale self-adhesively. Or it may be formed by removal of material from the scale, guided by the applicator or template. Or the applicator may comprise a strong permanent magnet which applies further magnetisation to a region of the scale.

Abstract: A non-contact sensor system is provided that comprises a first sensor element disposed within a first member having an axis Y, and a second member configured to rotate about the axis Y at a value X. The second member is configured to interface with the first member. The non-contact sensor system further comprises a second sensor element disposed on the second member proximate the first sensor element without physically contacting the first sensor element, and the first sensor element and the second sensor element are operatively coupled to facilitate sensing the value X. The non-contact sensor system may be configured to sense velocity, acceleration, and other values.

Abstract: A method for integrating a measurement device for use in measuring a machine component includes providing a coordinate measuring machine (CMM) and combining eddy current (EC) capabilities and CMM capabilities to form an inspection probe. The method further includes installing the inspection probe on the CMM so that the inspection probe measures external boundaries of the machine component with the CMM capabilities and substantially simultaneously measures at least one of internal boundaries, internal defects, surface defects, and material properties of the machine component with the EC capabilities, which are directly linked to actual component dimensional information provided by CMM. The inspection data can be simultaneously linked to and/or displayed with a CAD model to enable a direct comparison between the inspection data and the nominal requirements specified on the CAD model.

Abstract: An apparatus and method are disclosed for detecting flaws in electrically conductive materials by observing properties of the back-EMF of the eddy current field generated by driving magnetic flux through the object to be examined. The input signal may include sweeps at several frequencies, and may do so at one time under the principle of wave superposition. The sectorial observations of eddy currents summations may be compared to a known datum for a defect free material, the presence of anomalies in eddy field back EMF divergence tending to provide an indication of an irregularity in the underlying eddy field, and hence in the underlying material itself. The portable unit may have a number of different configurations depending on the nature of the object to be examined, be it a flat or large radius plate, a flange, a rail, or some other structural element.

Abstract: A magnetic sensor according to the invention includes: a detector detecting the intensity of magnetic field; a comparison portion comparing the result of the detection with a set threshold value and outputting an output signal corresponding to the result of the comparison; and a threshold-value adjuster adjusting the threshold value. Thus, inconveniences due to a reverse magnetic field phenomenon or magnetic-field offset phenomenon can be solved as simple as possible.

Abstract: The present invention discloses a novel magnetic sensor device performing direct magnetic field imaging, comprising a probe having a conical tip portion which is configured as a sensor having two superconductors separated by a thin non-superconducting layer (such as a Josephson junction based sensor), where the non-superconducting layer is located at the apex portion of said conical tip, thereby defining electron tunneling region(s) at said apex portion. The technique of the present invention enables the sensor device to be very small and to be brought very close to the sample surface.

Abstract: The invention relates to a method and a sensor device (1) for measuring a magnetic field comprising a first circuit (4) including a magneto sensitive sensor element (2) and a current source (5) and a second circuit (6) including a signal generator (7) and a coil (3) producing a excitational magnetic field at the sensor element (2), wherein the output signal of the sensor element is processible such that a second derivative of the sensor signal and the signal of the signal generator are derivable which are processible such that a countable signal is resulting being a measure of the magnetic field.

Abstract: A detection system comprising a plurality of magnetic field generators and a plurality of magnetic field detectors located adjacent to a detection area, and a control system arranged to generate magnetic field using the generators, and, for each of the generators, to make measurements of the magnetic field generated using each of the detectors, and processing means arranged to process the measurements to generate a data set characterising the detection area.

Abstract: A current sensor includes an annular magnetic core that includes a closed magnetic path including a void in a portion thereof, and a magnetic body for focusing flux of a magnetic field generated around a conductor that carries a measured current, and a magnetic detecting portion for detecting flux of a magnetic field generated in the void of the magnetic core. The magnetic core includes a plurality of pairs of stepped portions on a pair of opposing end surfaces that form the void, the stepped portions descending along a direction separating from the conductor.

Abstract: Methods, systems, software arrangements and storage medium for measuring the magnetic field correlation function (“MFC”), and more particularly, to methods for measuring the magnetic field correlation function utilizing asymmetric spin echoes. Asymmetric Dual Spin Echo Sequences (“ADSE”) and Echo Planar Imaging Asymmetric Dual Spin Echo Sequences (“EPI-ADSE”) may be employed to apply multiple echoes to a sample and acquire data from which the MFC may be determined.

Abstract: In a method and control system for producing two-dimensional diagnostic MR images using a magnetic resonance imaging scanner, a first three-dimensional MR image data set of a predetermined region within a body is produced using the magnetic resonance imaging scanner with an initial resolution. A second three-dimensional MR image data set of the predetermined region with a second resolution is then produced using the magnetic resonance imaging scanner, the second resolution being higher than the first resolution. Using the first three-dimensional MR image data set, layers are determined for the diagnostic two-dimensional MR images to be produced. The two-dimensional MR images are then computed from the second MR image data set for these layers automatically.

Abstract: In a magnetic resonance method and apparatus for determining a magnetization transfer constant a first MR signal sequence is acquired from an object being examined using a spin echo based imaging sequence, a second MR signal sequence is acquired from the object being examined using a spin echo based imaging sequence having basically identical imaging parameters to the first MR signal sequence, with the exception that the energy level of the RF pulses for exciting the magnetization in the first MR signal sequence and the energy level of the RF pulses for exciting the magnetization in the second MR signal sequence are different. The magnetization transfer constant is determined based on the signal differences between the first and second MR signal sequences.

Abstract: A method for image reconstruction that utilizes a generalization of compressed sensing is provided. More particularly, a method for homotopic l0 minimization is provided, in which a series of subproblems that asymptotically approach a solution to the l0 minimization are iteratively solved. These subproblems include utilizing concave metric prior functionals in the traditional compressed sensing framework. Substantially undersampled image data is acquired from a subject, for example, with a medical imaging system, such as a magnetic resonance imaging (“MRI”) system or a computed tomography (“CT”) system. Using the provided method, undersampling on the order of around 96 percent can be achieved while still producing clinically acceptable images.

Abstract: In a method and an arrangement for shimming a cylindrical magnet system, that has a cylindrical magnet having a bore therein with an axis extending therethrough, and a gradient coil assembly located within the bore, shimming is accomplished by stacking a number of planar pieces of shim material in each of said tubes, with each of the tubes having an axis parallel to the axis of the cylindrical magnet, and with the planar pieces of shim material and stacked in the tubes in respective planes that are perpendicular to the axis of the cylindrical magnet.

Abstract: The present invention provides microcoil-based detectors for detection of an analyte in a fluid, and methods for their use. In particular, the detectors contain a permanent magnet (206) and a gradient magnetic field generator.

Abstract: In a transmission method and receiver for magnetic resonance signals, the receiver has an in vivo coil and an ex vivo coil that are independent of each other. The in vivo coil is disposed within the rectum of a human body for acquiring the magnetic resonance signals generated by the excitation of a radio-frequency transmitter, and transferring the acquired magnetic resonance signals to the ex vivo coil by electromagnetic coupling. The ex vivo coil is to be disposed outside the human body for receiving the magnetic resonance signals from the in vivo coil by the electromagnetic coupling. It is thus not necessary to make a mechanical connection from the in vivo coil to the outside, so it is very convenient for use.

Abstract: The invention relates to a localization system for localizing an underground object for an earthmoving machine comprising a working part. Said localization system comprises a fastening component and a detector component. The fastening component can be arranged on the working part for example by means of magnets. The detector component is adapted to detect the object using an electromagnetic field that can be associated with the object and is arranged on the fastening component so as to swing like a pendulum, thereby effecting an alignment of the detector component under the effect of gravity. Optionally, the localization system comprises an arithmetic component for deriving a distance information of the object from the detected value. The localization system also comprises a display component for displaying and/or forwarding the detected value and/or the distance information.

Abstract: A method, apparatus and computer program for detecting an AC chassis fault on one or more DC/AC converters having a load is disclosed, including receiving a chassis voltage VChassis signal from between DC link and a chassis ground from the DC/AC converter, capturing a side band harmonic of the chassis voltage VChassis signal, determining a peak magnitude value related to the side band harmonic, comparing the peak magnitude value to a predetermined threshold value, wherein if said peak magnitude value equals or exceeds the predetermined threshold value, an AC chassis fault condition is detected.

Abstract: A method of detecting a ground fault condition between a direct current power system and the chassis ground of an electric or hybrid-electric vehicle is provided. The method includes sequentially opening and closing a first switch connected between a positive node of the direct current power system and the chassis ground of the vehicle and a second switch connected between a negative node of direct current power system and the chassis ground. The sequential opening and closing of the first and second switches charges and discharges an inherent capacitance present between the metal components of the direct current power system and the chassis. First and second currents are created as the inherent capacitance is charged and discharged. Measurements of the created first and second currents are then used to determine whether a ground fault condition exists between the direct current power system and the vehicle chassis ground.

Abstract: A power interruption detecting system includes an electronic device and a power interruption detecting device. The electronic device includes a power supply, a protection circuit, a main circuit and a recording structure. The power supply includes a first power supplying module and a second power supplying module. The protection circuit is connected in parallel to the first power supplying module. The main circuit is connected in parallel to the first power supplying module. The recording structure is connected to the main circuit and configured for collecting a number of values of working voltage of the main circuit. The power interruption detecting device is configured for determining a cause for a shutting down problem happened to the electronic device, according to the values of the working voltage.

Abstract: Circuit configuration for error reporting, having a signal transmitter (1) for issuing error signals, having an error reporting line (46) that is connected with an error report evaluation device (6), having a coupler (2) for galvanic separation of the error reporting line (46) from the signal transmitter (1), and having a power supply (5) for making available an operating voltage for the coupler (2). A connection circuit (3) is provided between coupler (2) and error reporting line (46), which places the error reporting line (46) at a predetermined potential, the error report potential, if the operating voltage of the coupler (2) is insufficient. The connection circuit (3) can furthermore be controlled by the coupler (2), in such a manner that if the signal transmitter (1) issues an error signal, the connection circuit (3) places the error signal onto the error reporting line (46).

Abstract: The invention discloses a testing system and a testing method. The testing system includes a testing platform and a fetching device. The testing platform includes a metal base plate, a DUT board, a testing stand and a metal wall. The DUT board is disposed on the metal base plate. The testing stand is disposed on the DUT board. The metal wall is disposed on the metal base plate and surrounds the testing stand. The fetching device is movably disposed above the testing platform and used for placing a DUT on the testing stand. A metal covering plate of the fetching device corresponds to the metal wall of the testing platform. When the fetching device places the DUT on the testing stand, the metal covering plate cooperates with the metal wall and the metal base plate of the testing platform to form an isolated space, so as to isolate the DUT.

Abstract: An open terminal detection device that detects an open terminal, including: a transistor that is supplied with a base current from a current source in which an amount of current supply decreases corresponding to an increase in an external impedance of the terminal; a diode that limits discharge of a base charge of the transistor; and an output circuit that outputs an output signal in coordination with on/off switching of the transistor.

Abstract: Provided is a test apparatus that tests a device under test, having two operational modes which are (i) an edge strobe mode in which the test apparatus judges acceptability of a value of an output signal from the device under test at sequentially designated reference timings, based on expected value information, and (ii) a multi-strobe mode in which the test apparatus judges the acceptability of values of the output signal at a plurality of strobes for each reference timing, based on expected value information, the plurality of strobes being generated based on the reference timing, and comprising a conversion control section that converts an expected value pattern supplied thereto into expected value information to be used in the edge strobe mode or into expected value information to be used in the multi-strobe mode, depending on which of the edge strobe mode and the multi-strobe mode is selected.

Abstract: A device is configured to evaluate electromagnetic characteristics of an integrated circuit. The device includes a fluid chamber, a first impeller, a second impeller, and a radio frequency measurement antenna. The fluid chamber is configured to receive the integrated circuit and to cool the integrated circuit. The first impeller is disposed within the fluid chamber and configured to distribute a first electromagnetic field produced by the integrated circuit within the fluid chamber along a first axis. The second impeller is within the fluid chamber and configured to distribute the first electromagnetic field produced by the integrated circuit within the fluid chamber along a second axis. The radio frequency measurement antenna is disposed proximate the fluid chamber and configured to measure an electric field and a magnetic field of the first electromagnetic field.

Abstract: A device (1; 1b) for measuring the thickness of a layer of material (20) is provided with reading means (2) and control means (3) connected to the reading means (2). The reading means (2) include a microwave planar type sensor (6) and an A/D converter (8) connected to the microwave sensor (6) and arranged in proximity of the microwave sensor (6).

Abstract: An inductive conductivity measurement cell of the invention includes: sending coil, a receiving coil, and a coil support body having an annular, sending coil chamber and an annular, receiving coil chamber, wherein there extends through the coil support body at least one section of a closed media path, which passes through the sending coil chamber and through the receiving coil chamber, characterized in that the coil support body has first connection bores, which extend from a surface of the coil support body to the sending coil chamber and through which the connection lines of the sending coil extend, and second connection bores, which extend from a surface of the coil support body to the receiving coil chamber and through which the connection lines of the receiving coil extend. The connection lines of the sending coil in the first connection bores are shielded from the connection lines of the receiving coil in the second connection bores by the coil support body.

Abstract: Some general aspects of the invention relate to a circuit and to a method for analog computation, for example, using switched capacitor integrated circuits. In some examples, a circuit includes a first group of capacitors and a second group of capacitors that may store charges during circuit operation. The first and/or the second group of capacitors may include multiple disjoint subsets of capacitors. An input circuit is provided for receiving a set of input signals and for inducing a charge on each of some or all capacitors in the first group of capacitors according to a corresponding input signal. Switches, for example, transistors controlled by a sequence of clock signals, are used to couple different sets of capacitors. Different configurations of the switches are used to form different sets of the capacitors among which charge can redistribute.

Abstract: The invention relates to a sensor device, in particular for detecting at least one object in a swivel region of a convertible top, comprising at least one sensor which is formed at least partly by a convertible top rod system. According to the invention, the sensor further comprises a conductor path structure connected in an electrically conductive manner to the convertible top rod system so as to form a sensor electrode. The invention further relates to a method for installing such a sensor device. Furthermore, the invention relates to a conductor path structure, in particular a flexible and substantially flat conductor path structure. According to the invention, said structure can be attached to a convertible top rod system, in particular to one or more links of a link system of the convertible top rod system, wherein the conductor path structure can be connected to the convertible top rod system in an electrically conductive manner via one or more contact regions.

Abstract: The invention relates to a method for the determination of diffusion coefficients and/or exchange coefficient of a material having electronic and ionic conductivity. The material is permeable to at least one gas. It is the object of the invention to provide a cost-effective, accurate method for the determination of the diffusion coefficient and of the surface exchange coefficient which can be carried out in a short time and can thus be used for a screening of materials, in particular for application in the field of permeation membranes. The procedure is followed in accordance with the invention such that a sample of the material is arranged in a measurement chamber and has an electric current passed through it for a determination of the electric resistance. In this respect, a gas mixture in which the respective gas is contained is conducted through the measurement chamber as a gas flow and the partial pressure of the respective gas in the gas mixture is changed periodically at regular intervals.

Abstract: A method of controlling a pre-charge process of a data line (21, 22) in an integrated circuit (100) comprises the step of monitoring a rate of change of a voltage applied to the data line (21, 22) for enhancing the security. Further a respective integrated circuit (100) is disclosed.

Abstract: A contact resistance test structure, a method for fabricating the contact resistance test structure and a method for measuring a contact resistance while using the contact resistance test structure are all predicated upon two parallel conductor lines (or multiples thereof) that are contacted by one perpendicular conductor line absent a via interposed there between. The test structure and related methods are applicable within the context of three-dimensional integrated circuits.

Abstract: In one embodiment, the reliability of the L2 power and/or ground sub-arrays of contacts of a functional integrated circuit device is verified by applying a reference voltage to a selected contact in sub-array and sequentially measuring the voltage at other contacts in the sub-array. If the voltage levels are greater than a threshold voltage level then the functional integrated circuit device is verified as being reliable.

Abstract: Provided is a test apparatus for testing a device under test, comprising a multi-strobe generating section that generates, for each prescribed test cycle, a multi-strobe that includes a plurality of strobes arranged at prescribed time intervals; a data detecting section that detects a logic value of a response signal output by the device under test, according to each strobe; and a data width detecting section that detects a data width indicating a period during which the logic value of the response signal matches a prescribed expected value, based on each change point of a logic value output by the data detecting section.

Abstract: A reliable and durable method of testing of printed circuit boards is presented. Test access components are placed in contact regions for providing electrical connectivity between test probes and the printed circuit board. In some cases, a test access component may be a surface mount resistor. The test access component may provide two points of contact for test probes to make electrical and mechanical contact with the printed circuit board. Test access components may also provide for increased durability of testing, allowing for a greater number of test contacts to be made between test probes and printed circuit boards than were previously possible.

Abstract: A method of testing a wafer capable of minimizing the asymmetrical thermal deformation of a probe card when a wafer is tested using a probe card and of minimizing the number of times of tests to effectively test a large area wafer and a probe card for the same is presented. For the wafer test method for testing semiconductor chips on a wafer using a probe card, the method includes creating virtual repeating units corresponding to N semiconductor chips, wherein the N is natural number larger than or equal to 2, arranging the plurality of repeating units on the wafer and moving the probe card or the wafer N times and testing the semiconductor chips on a wafer, wherein the semiconductor chips in the repeating units are sequentially tested one by one per each touchdown. Also, the probe cards to realize above mentioned method have been described.

Abstract: An apparatus for testing an electrical property of a semiconductor device includes a substrate support unit, a tester head above the substrate support unit, the tester head including a base, a probe card connected to the base of the tester head, and a temperature control unit within the base of the tester head, the temperature control unit being configured to control temperature of the probe card by heat transfer with the probe card.

Abstract: A Micro-Electro-Mechanical-Systems (MEMS) interconnection pin is fabricated on a sacrificial layer, which is formed on a conductive layer and a substrate. The MEMS interconnection pin has a pin base attached to a frame that has direct contact to the conductive layer. The sacrificial layer is then removed, at least partially, to detach the MEMS interconnection pin from the substrate. In one embodiment, the MEMS interconnection pin has a pin base, two springs extending out from two different surfaces of the pin base, and a tip portion attached to each spring. The tip portions include one or more contact tips to make contact to conductive subjects.

Abstract: A method and system of system-on-chip design that provides the benefits of reduced design time, a smaller die size, lower power consumption, and reduced costs in chip design and production. The process seeks to remove the worst performance and worst power case scenarios from the design and application phases. This is accomplished by planning the power supply voltage in the design phase along with its tolerance with process corner and temperature combinations. The established plan is then applied with communications between power supply integrated circuits and load system-on-chip.

Abstract: The present invention relates to a detection circuit for detecting that a power supply unit is connected to a wrong supply voltage. Said detection circuit comprises a first voltage divider (24, 26, 28) connected to the output terminals (20, 50) of a rectifier (16) of the power supply unit, a second voltage divider (26, 32) connected to a first power input terminal (10) of the power supply unit and to one of the output terminals (20, 50) of the rectifier (16), and a circuit breaker (14) connected to the first power input terminal (10) of the power supply unit and to an input terminal of the rectifier (16), wherein at least one partial voltage of each voltage divider (24, 26, 28; 26, 32) is used a signal (22, 46) for identifying the wrong supply voltage. The invention relates further to a method for detecting that a power supply unit is connected to a wrong supply voltage.