Abstract: The device may be used to, for example, function test sensors in high voltage plants and signal boxes. The device makes it possible to function test sensors in high voltage plants, independent of where the sensors are located. The elongated device has one end that is provided with an insulated handle part and a flexible component that has a light generating part at an outer end thereof. The light generating part emits a light that is similar to the light of an electric arc.

Abstract: A system for detecting defects in an interlayer dielectric (ILD) interposed between first and second conductive lines lying adjacent each other along a first plane is provided. A processor controls general operations of the system. A voltage source adapted to apply a bias voltage between the first and second conductive lines is employed to induce a leakage current across the ILD. A light source for illuminating at least a portion of the ILD is used to enhance the leakage current. A magnetic field source applies a magnetic field in a direction orthogonal to the leakage current. The magnetic field deflects carriers in a direction substantially perpendicular to the first plane. A voltage monitor measures a voltage generated across third and fourth conductive lines, the third and fourth conductive lines lying adjacent each other along a second plane which is substantially perpendicular to the first plane. The voltage monitor is operatively coupled to the processor.

Abstract: A process for monitoring the state of microcrystalline change of solid materials, by observing the frequency of a load-pull oscillator which is RF-coupled to the material under test (preferably by a simple single-ended RF probe). Areas where this technique is of particular interest are in monitoring the curing of shaped aerodynamic composite materials, and in monitoring the curing of concrete and cement compositions.

Abstract: A leakage tester includes multiple circuits capable of simulating the impedance of the human body to electrical current under a variety of conditions, and in which the multiple circuits can be selected using a single menu-based operator interface for testing both normal-line and single-fault conditions such as open-neutral, reversed-line, and open-ground conditions, as well as for performing additional types of safety compliance tests including dielectric withstand, insulation resistance, and ground bond or continuity tests, in any sequence.

Abstract: A contact resistance check circuit and method for verifying that a sufficient electrical connection is established between a source and a sense lead of a Kelvin connection. The circuit includes a microprocessor for driving a transformer that is connected to the source/sense probe (i.e., contact resistance) with an input pulse. The input pulse is altered in relation to the magnitude of the contact resistance to produce a check pulse. A comparator is used to compare the check pulse with a threshold voltage and for generating a fault indication signal. A flip flop then stores the fault indication signal so that the fault indication signal may be monitored by the microprocessor.

Abstract: The invention consists of a system to compensate for the parasitic signal induced by a parasitic impedance in the signal path. An auxiliary signal, outside of the frequency band of the desired signal, is introduced to evaluate the effects of the parasitic impedance. A compensating signal is then generated by simulating the effects of the parasitic impedance on the desired signal. Those simulated effects are then superimposed over the normal signal path with a phase adjusted to eliminate the effects of the parasitic impedance on the total resulting signal.

Abstract: A method for Voltage Stability Analysis of a bulk power supply system is taught. Briefly stated, a computationally efficient method is disclosed which is appropriate for low and high voltage applications as well as differing types of loads and load changes, i.e. reactive or otherwise, and which is usable with a multitude of different bulk power supply system systems. More particularly, a nose point of a curve for which MVAr, MW or MVA distances to voltage are calculated, using a generalized curve fit in order to compute an equivalent or surrogate nose point. This is done by approximating a stable branch and creating a voltage versus power curve, determining a plurality of stable equilibrium points on the curve, using the plurality of determined stable equilibrium points to create and fit an approximate stable branch, calculating an approximate voltage collapse point and thereafter a voltage collapse index.

Abstract: Apparatus and method for low cost monitoring the level of signal at a test point in a system for susceptibility to electromagnetic fields. A probe, including a detector diode, and a non-metallic, electrically overdamped conductor, which is transparent to the electromagnetic field, is used to monitor the signal level at a test point as an amplitude modulated radio frequency carrier. The carrier is transmitted to a monitor outside of the range of the electromagnetic field using a transmission link, such as an optical waveguide transmitter, that is transparent to the electromagnetic field when the system under test fails. The system under test can then be removed from the electromagnetic field and, for each frequency at which the system failed, a voltage can be injected, using a voltage injection probe, into the system at another point to recreate the detected level of signal at the test point that was coupled into the system from the electromagnetic field.

Abstract: In devices for determining and/or monitoring a predetermined level with a sensor that is excited to perform mechanical oscillations at its self-resonant frequency by means of an electronic excitation circuit which is excited via a piezoelectric excitation and a reception transducer and an evaluation circuit for triggering display and/or switching processes, there exists the difficulty that the natural frequencies of the sensors are different due to the manufacturing conditions, and that the operating frequency must be adjusted individually for each sensor. This disadvantage makes repair and maintenance procedures quite difficult.

Abstract: A contact hazard meter used to measure electromagnetic field induced currents which would flow through a human body to ground upon physical contact with an item carrying such field induced currents includes a conductive contact, a human equivalent circuit coupled to the conductive contact and an electronic circuit coupled to the human equivalent circuit for measuring and displaying a measurement of current flowing from the item and through the human equivalent circuit when the conductive contact is placed in physical contact with the item carrying the field induced currents. The human equivalent circuit approximates the impedance of the human body at varying frequencies. The contact hazard meter has a plurality of range settings, one setting providing the resultant current as a percentage of a safety guideline maximum permissible exposure value.

Abstract: A pulse discharge circuit for pulse testing an integrated-circuit device under test (DUT) is provided which uses three separate switching relays S1, S2, and S3, which are operated in a predetermined sequence. For charging the capacitance of a pulse-forming transmission line, the relay contact of S1 is closed while the relay contacts of relays S2, S3 are both open. For discharging the charge on the transmission line to form a test pulse, the relay contact of S1 is first opened, and the relay contact of S2 is then closed while the relay contact of S3 is open. After each test pulse is generated and applied to a DUT, the condition of the DUT is determined by a leakage current measurement. The relay contact S2 is opened to isolate the pulse generator circuit and then the relay contact S3 is closed.

Abstract: An instrumentation interface circuit controlled by a microprocessor of a data acquisition system enables identification of the type of input/output devices that are connected to its inputs through a systematic analysis of the characteristics of the connected devices, the systematic analysis including monitoring the current through and the voltage across the devices as different drive signals are applied to the connected devices, the interface circuit including a conditioning circuit having a drive circuit which is controlled by the microprocessor for providing the drive signals, a current sensing circuit for sensing the load current flowing through the connected device, a voltage sensing circuit for sensing the voltage across the connected device, and a switchable feedback circuit which is controlled by the microprocessor to selectively feed back the load current or the sensed voltage to the input of the drive circuit to establish the drive signals for the connected device.

Abstract: A portable hearing protection device evaluation apparatus which can be taken into the field to measure noise attenuation of a muff type hearing protection device under actual working conditions is provided. The apparatus includes two miniature microphones, one positioned inside a muff near the ear, the other positioned outside the muff to detect the noise in the environment. These two microphones simultaneously receive input signals which are provided to circuitry which determines and displays a single number output representing the noise attenuation.

Abstract: Circuitry for testing the ability of an intermediate range nuclear instrut to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is applied to the instrument. When the LED is off, a constant current is applied. An inductor opposes battery current flow when the LED is on.

Abstract: A circuit and method for measuring resistance in an active and high temperature environment is provided using a low frequency square wave as an input. The square wave input is fed through the unit under test into a full-wave rectifier and RMS circuit. The full-wave rectifier and averaging circuit cancel out errors caused by the Seebeck effect and noise. The resulting d.c. signal is proportional to the resistance of the unit under test and can be displayed.

Abstract: In a switchable impedance tester for measuring very small impedances, the effect of switch impedances is eliminated by connecting the test load between two switching transistors in their emitter-collector circuit, and driving them with operational amplifiers arranged to urge their inputs into equality. A test voltage source is connected across first inputs of the amplifiers, and the other inputs are connected between the respective transistors and the load. This produces an operational condition in which the voltage across the load is independent of the parameters of the switching transistors, i.e. the switching transistors appear to have zero impedance.