Abstract: A method of measuring inductance or inductive reactance of a sample is provided. The method comprises the steps of: (a) providing an instrument for measuring the inductance or the inductive reactance of the sample; (b) subjecting a portion of the instrument to different temperatures and recording data corresponding to the performance of the instrument portion at each temperature; (c) measuring the inductance or the inductive reactance of the sample using the instrument; and (d) correcting the measurement of inductance or inductive reactance for temperature based on the performance data.

Abstract: A current sensor and a method for measuring currents on an integrated circuit in an isolated manner. The current sensor uses a Peltier device as a thermal difference generator to generate a first temperature at a temperature generating junction and a second temperature at a second temperature generating junction. The two temperature generating junctions being spaced apart from one another and where the temperature difference between the first and second temperatures is a function of the sampled current. A Seebeck transducer operating as a thermal difference sensor has a first temperature sensing junction thermally coupled to the first temperature generating junction and a second temperature sensing junction thermally coupled to the second temperature generating junction.

Abstract: An object is to provide a highly-sensitive, pyroelectric infrared sensing method and apparatus which can detect infrared temperature with high sensitivity throughout the entire electromagnetic wave range including millimeter waves and radioactive rays.

Abstract: An electricity meter which, in one embodiment, includes a temperature sensing unit for determining a signal representative of the temperature within the meter is described. In the one embodiment, the meter includes a current sensor, a voltage sensor and a processing unit. The current sensor generates an signal representative of a line current and the voltage sensor generates a signal representative of a line voltage. The current and voltage sensor and temperature sensing unit outputs are coupled to the processing unit. The processing unit includes an analog to digital (A/D) converter, a digital signal processor (DSP) and a microcomputer. The digital outputs of the A/D converter are connected to the DSP. The outputs of the DSP are connected to the microcomputer. Temperature characteristics of the meter are stored within the DSP.

Abstract: A power detector (50) detects a power level of an amplified signal (S20) produced by a power amplifier (16) on the same integrated circuit (100). The power detector compensates for an effect of temperature variations on the magnitude of the detected power level.

Abstract: A power detector (50) detects a power level of an amplified signal (S20) produced by a power amplifier (16) on the same integrated circuit (100). The power detector compensates for an effect of temperature variations on the magnitude of the detected power level.

Abstract: A method of removing bias drift from the output signal of a sensor is provided. The method includes sensing a condition with a sensor and generating an output signal, differentiating the output signal, and comparing the differentiated output signal with a threshold change. The method also includes the steps of determining the presence of bias drift based on the comparison, generating a bias adjustment command signal based on the determined presence of bias drift, and adjusting the sensed signal generated by the sensor in accordance with the bias adjusted command signal so as to remove bias drift from the output signal.

Abstract: The method and apparatus for detecting maximum and minimum values, and the torque detecting apparatus and steering apparatus comprising the maximum and minimum values detecting apparatus can detect maximum and minimum values of detection signals without setting a particular value such as a threshold. A signal processing unit provided at the maximum and minimum values detecting apparatus detects a crossing of two detection signals outputted from two MR sensors, and detects maximum and minimum values of the signals based on maximum and minimum values of the signals detected within a time interval defined by the time when a crossing is detected.

Abstract: A power sensing RF termination comprising a calibration means allows the user to correct for part-to-part variation, miss match loss and output offset. The power sensing RF termination comprises a first and second temperature sensitive resistors connected at a first common junction, a switching means for connecting either an RF input or a DC power reference to the first common junction, a first switch for connecting either a DC voltage source or a first current detecting resistor to the first temperature sensitive resistor, and a second current detecting resistor connected to the second temperature sensitive resistor. A first output terminal is connected to the junction between the first switch and the first temperature sensitive resistor. A second output terminal is connected to the first common junction. A third output terminal is connected to the junction between the second temperature sensitive resistor and the second current detecting resistor.

Abstract: A power supply controller having final test and trim circuitry. In one embodiment, a power supply controller for switched mode power supply includes a selector circuit, a trim circuit, a shutdown circuit and a disable circuit. The trim circuit includes a programmable circuit connection that can be selected by the selector circuit by toggling a voltage on an external terminal such as for example a power supply terminal, a control terminal or a function terminal of the power supply controller. The programmable circuit connection in the trim circuit can be programmed by applying a programming voltage to the external terminal. The shutdown circuit shuts down the power supply controller if the temperature rises above an over temperature threshold voltage. The shutdown circuit includes adjustment circuitry that can be used to test the shutdown circuit. The adjustment circuitry can adjust and reduce the over temperature threshold of the power supply controller.

Abstract: Electronic scale including a line power voltage supply (5); a line switch (9); and a separate voltage supply (20), which is independent of the line powered voltage supply (5) and which supplies at least one clock module (22) with voltage. The scale has a normal operating state in which all the electronic components are supplied with voltage, a standby operating state in which the essential heat-generating components are switched on while components susceptible to deterioration over time and the display (3) are switched off and, in addition a further operating state (sleep mode) in which the line switch (9) is open. After expiry of a prescribed time and/or at a prescribed time of day, the clock module (22) automatically terminates the further operating state and switches over into the normal operating state or the standby operating state.

Abstract: A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized.

Abstract: A current sensor assembly of planar form arranged for connection in series with an electrical circuit. The circuit includes a first and second conductor. The sensor assembly includes a first conductive member adapted to contact the second conductor in the circuit. A second conductive member is adapted to contact the second conductor in the circuit. A thin layer of conductive material is connected at one end to the first conductive member and at is other end to the second conductive member so that current flow in the circuit between the first and second conductors is via the thin layer. A support supports the thin layer along its entire length. At least a part of the support contacts the thin layer is electrically insulative. The thermal conductivity of the support is different at different points along the length of the layer so that heat disposition is different at the different points and hence the temperature rise caused by current flow through the layer is different.

Abstract: A thermoelectric measurement converter is disclosed, which forms the output signal as the product of the instantaneous values of two input signals; wherein the measurement converter comprises at least one electronic resistor and at least one temperature sensor, both being disposed on a common base which is heat insulated with respect to the environment.

Abstract: A temperature sensing circuit suitable for integration with a power semiconductor device (MOSFET/IGBT) includes temperature-sensing p-n diode means (D1, D2, etc . . . ) integrated together with first and second IGFETs (M1 and M2). A current path through the temperature-sensing p-n diode means (D1, D2, etc . . . ) provides a voltage drop (Vf) having a negative temperature coefficient. The IGFETs (M1 and M2) are coupled in separate current paths from each other so as to have separate gate-to-source voltage signals (Vgs1 and Vgs2) between their source and gate electrodes (s and g). The gate-to-source voltage (Vgs1) of the first IGFET (M1) has a negative temperature coefficient of greater magnitude than the temperature coefficient (if any) of the gate-to-source voltage (Vgs2) of the second IGFET (M2). One of the source and gate electrodes (s or g) of the first IGFET (M1) is coupled to the p-n diode means (D1, D2, etc . . .

Abstract: A detector facilitates visualization of electromagnetic radiation, including radio frequency radiation. The electromagnetic radiation is converted to thermal energy by partial absorption of the radiation, and is made visually observable by coupling the pattern of thermal energy to a thermally-responsive imaging surface, such as a liquid crystal display.

Abstract: A circuit for measuring the duration of a cut-off period in the power supply to an electronic system, for example the control system of a motor vehicle starter, comprises a voltage splitting bridge and a processing unit receiving the output of the splitting bridge. The bridge supply voltage is derived from the power supply to the electronic system, and the bridge has a branch which includes a temperature variable resistor. The processing unit determines the duration of the cut-off period as a function of the value of the output voltage from the splitting bridge at the end of a cut-off period.

Abstract: A temperature compensation circuit for a power measurement device includes an input sensor, with a temperature-dependent transmission factor (K.sub.H,T), connected to a signal processor with a temperature-dependent transmission factor (K.sub.S,T). Transmission factor (K.sub.S,T) of the signal processor is inversely proportional to a temperature-dependent reference voltage (U.sub.R,N,T), which is inputted to the signal processor in order to render the combined transmission factor (K.sub.H,T .multidot.K.sub.S,T) temperature independent. To accomplish this, a temperature coefficient value of reference voltage (U.sub.R,N,T) must be equal to the sum of a temperature coefficient value of transmission factor (K.sub.H,T) and a temperature coefficient value of transmission factor (K.sub.S,T). The desired temperature coefficient value of reference voltage (U.sub.

Abstract: A method for compensating an offset voltage temperature drift in a semiconductor strain gage sensor in which a temperature-sensitive power supply is modeled as the one for providing the output voltage V.sub.0 =KV.sub.S (1+.alpha.T), and, under the condition that the resistance of the compensating resistor and the coefficient .alpha. are within practical ranges, respectively, the parameter K is determined so as to minimize the compensating error, thereby both of the primary order term and the secondary order term with respect to the temperature in the offset voltage of the strain gage can be compensated so that the offset temperature drift can be reduced.

Abstract: An electro-optics current sensing system for sensing and avoiding thermally induced measurement errors in a current sensor includes a beam generator, such as a light emitting diode or a laser diode, thermally coupled to the current sensor for encoding into the optical beam supplied by the beam generator both temperature and sensed current information. An electro-optics (E/O) demodulator which includes a wavelength division multiplexer (WDM) demodulates the encoded optical beam to recover the temperature and sensed current information from a pair of demodulated signals which can be further processed for filtering resistivity changes from the sensed current measurement.

Abstract: A Rogowski coil is used as a precise current and temperature measuring device (in particular a device that is highly insensitive to temperature variations). The Rogowski coil is of the type including at least one printed circuit plate provided with a circular cutout. The coil is implemented by metal deposits on each of the two faces of the plate and extending along radii such that geometrical projections thereof pass through the center of the cutout. Electrical connections between the radii on one face and those on the opposite face are implemented by plated-through holes that pass through the thickness of the plate.

Abstract: A current sensor includes first and second branches interconnected by a center conductor magnetically coupled to an annular current comparator for producing an output signal related, in magnitude and phase, to an input current. The input current divides, according to a predetermined relationship, between the first and second branches such that the current in the center conductor interconnecting the first and second branches is also related to the input current. A current is induced in the annular current comparator in relation to the current in the center conductor and, thus, in relation to the input current. Secondary windings are wound about and magnetically coupled to the annular current comparator for producing an output signal responsive to the current induced within the annular current comparator.

Abstract: In one embodiment, a thermal conductivity detector in a gas chromatograph is provided with a sensor connected in a resistive bridge with an alternating voltage applied to the bridge. Changes in thermal conductivity of a gas in the sensor cause changes in the temperature and resistance of the sensor which unbalances the bridge. A component of the voltage difference caused by the imbalance varies as the third harmonic of the applied voltage and has a magnitude related to the thermal conductivity of the gas. This third harmonic is measured to determine the thermal conductivity of the gas. In another embodiment, a sensor in a cavity through which gas flows is alternately operated at two different temperatures, and a difference in power required for operation is measured. The difference is independent of the temperature of the cavity walls and proportional to the thermal conductivity. This difference is measured to determine the thermal conductivity of the gas.

Abstract: A system for determining the current carrying capability of one or more overhead power transmission lines monitors one or more spans of each line on real-time basis and identifies the span having the lowest current carrying capacity which in turn establishes the maximum capacity of the entire line. The thermal state of each monitored line span is determined by measuring the conductor temperature, line current, solar radiation, ambient temperature, and in some cases wind speed and wind direction. These parameters are montiored by a sensor-transmitter unit that may be removably clamped on the line conductor which may range in size from one to several inches in diameter, and includes a radio transmitter for transmitting sensed data to a receiving substation.

Abstract: An apparatus for monitoring current through a lamp circuit that uses a series resistance shunt in the circuit with one end connected to a current source and the second end connected to the lamp. The apparatus includes a comparator that is connected across the shunt and has a threshold switching voltage wherein a voltage across the shunt that is larger than the threshold switching voltage will switch the comparator on and a voltage across the shunt that is smaller than the threshold switching voltage will switch the comparator off. A biasing circuit, connected to and controlling the comparator, temperature compensates the threshold switching voltage such that the threshold switching voltage changes proportionally to absolute temperature and controls a sensitivity of the threshold switching voltage to changes in a supply voltage of the circuit. In a preferred embodiment, the shunt is a portion of the printed board trace.

Abstract: As the dielectric constant and the halfwave voltage of electro-optic crystals having a fourfold axis of rotary inversion are oppositely dependent on the absolute temperature, but their product is nearly independent of temperature, temperature compensation in an ac voltage measuring system utilizing such an electro-optic crystal is provided by measuring the time averaged current through the crystal. Good electric isolation is achieved by a current sensing circuit which produces a pulsed light signal having a pulse rate proportional to the time averaged current through the crystal. The pulsed light signal is converted to an electrical signal for input to a digital computer which calculates therefrom, and from a reference current and voltage measured at a reference temperature, and a time averaged voltage measurement, a temperature correction factor which is applied to the crystal halfwave voltage used by the computer in calculating the instantaneous value of the voltage to be measured.

Abstract: A pressure sensor circuit (10A) is disclosed which preferably utilizes a piezoresistive pressure transducer (11A) having a substantial temperature coefficient of resistance to provide an inherent temperature variation which is used to implement offset temperature compensation for the circuit. Two operational amplifiers (OA1, OA2) are configured along with selectable resistors (R.sub.1, R.sub.9, R.sub.7, R.sub.8, R.sub.5, R.sub.6 and R.sub.4) to implement four adjustments of the circuit (10A) to adjust span (gain), offset and temperature variation of both span and offset to achieve a desired result. All this is achieved while implementing a common mode gain for the circuit (10A) which is less than 5 and preferably no more than 2.

Abstract: A temperature compensated level detector is disclosed in which a voltage multiplying rectifier is provided for rectifying and smoothing a high-frequency input voltage to obtain a DC output, and a bias voltage generator is added to said voltage multiplying rectifier, for providing a forward bias voltage. The bias voltage generator has a temperature compensating function.

Abstract: A current sensor employs a main resistor of a low temperature-coefficient material for producing a voltage drop proportional to a load current therein. A second resistor, also of a low temperature-coefficient material, and preferably having a resistance substantially exceeding that of the main resistor, is connected in parallel with the main resistor. The current divides between the main and the second resistors according to the ratio of their resistances. An output signal, reduced at least in accordance with a ratio of resistances of the first and second resistors, is obtained from the second resistor. Resistive heating of the main resistor is reduced by using a short path length in the direction of current flow and as large an area transverse to the direction of current as possible. A current transformer may employ the second resistor as a primary to step down further the current in the output signal.

Abstract: A measuring sensor of an electronic trip device of a circuit breaker comprises a shunt in the form of a hollow cylinder inside which there is located an electronic processing unit, comprising an amplifier circuit and an input resistance in good thermal contact with the internal face of the cylinder.

Abstract: The thermal time constant of fine metal wire segments, such as those used to initiate explosive reactions, is measured by passing a variable frequency source of current through the wire. The magnitudes of the sine and cosine components of the third harmonic of the voltage developed across the wire are detected and compared to each other to provide a control signal which is applied to the frequency source to change the its frequency in a direction which tends to make those components equal in magnitude. The magnitude of the control signal, when the third harmonic sine and cosine components are equal, is displayed as a function of the thermal time constant of the wire segment.

Abstract: A method and apparatus accurately measures temperature even if a temperature difference exists between cold junctions of the main thermocouple. An auxiliary thermocouple is connected to one leg of the main thermocouple to provide cold junction compensation. Extension leads are connected to both cold junctions to take thermo emf from the thermocouple. The leads are made from a material having a thermoelectromotive characteristic in agreement with the thermoelectromotive characteristic of the other leg at low temperatures at which the cold junction compensation is provided. A converter converts the thermo emf of the composite thermocouple into temperature. The converter can separately set interpolations for converting the thermo emf of the auxiliary thermocouple into thermo emf of the main thermocouple and for coverting the sum of the converted thermo emf and the thermo emf of the main thermocouple into temperature.

Abstract: The device of the invention comprises a main optical sensor (3) suitable for measuring a changing physical parameter, and a secondary optical sensor (6) suitable for measuring a disturbance which influences the measurement of said physical parameter, but for which the frequency spectrum is disjoint from that of the parameter. The sensors (3) and (6) are connected in series such that the main sensor serves to modulate the beam received by the secondary sensor.

Abstract: A watthour meter, preferably for a wye connected load, includes a current transformer for sensing the load current, a resistive voltage divider network for sensing the line voltage, and a measuring circuit for calculating the AC electrical energy consumption of the load based on the sensed load current and line voltage. The load consumption calculations are performed using a Mark-Space oscillator and amplitude modulator in the watt transducer chip. Reduced voltage from the resistive voltage divider network is fed into the input junction of the Mark-Space oscillator. A feedback resistor is connected from the output junction to the input junction of the oscillator. The feedback resistor and the voltage divider network are mounted on the same thermally conductive substrate so that each are subject to the same thermal effects.

Abstract: A temperature compensated power detector utilizes a temperature compensating diode connected to an inverting input of an amplifier to enable the amplifier to substantially cancel out undesirable temperature effects caused by a power level detector diode coupled to the non-inverting input of the amplifier. As a result, the amplifier output voltage tends to remain constant over temperature in response to a fixed power level being applied to the detector. A lookup table is utilized to determine the power level corresponding to a power detector output voltage of a particular magnitude.

Abstract: A parameter measuring apparatus includes a constant signal circuit incorporating a sensor having a known response to a given parameter for outputting a signal representing the parameter. The constant signal circuit further includes circuitry defining upper and lower limits of the parameter range. The parameter signal is provided to a sampling device such as current-to-frequency converter for providing an analog-to-pulse converted signal to a microprocessor. The apparatus further includes a switching arrangement coupled to and controlled by the microprocessor for switching into circuit the sensor or the circuitry defining the upper or lower parameter limits. The switching arrangement also eliminates internal switch resistance in the circuit for improved measurement accuracy.

Abstract: A method of measuring the strength of a DC current and a device for implementing this method are provided, forming an NMR shunt for measuring high currents. A magnetic coil is placed in series in the circuit in which the current to be measured flows, the temperature of the magnet is stabilized and the magnetic field is measured in the center of the magnet using an NMR probe.

Abstract: A system for circulating hot or cold liquid through a pad placed in thermal contact with a patient for thermal therapy. The system includes a flexible thermal pad with an internal channel for carrying the liquid and a pump assembly for circulating and optionally heating the liquid. The patient-contacting surface of the pad comprises a foam having a cushioned surface to reduce the risk of ischemia and enhance patient comfort. An open-cell foam structure absorbs and retains moisture for applying moist heat. The system is microprocessor controlled and includes a heater to warm the liquid to a selectable temperature for heat therapy. A display selectively indicates set-point or actual liquid temperature in either .degree. F. or .degree. C. as desired. Safety features include three separate over-temperature sensors, a tilt switch and a float switch which de-energize both the heater and the pump when an abnormal temperature is sensed, the unit is tipped or a low liquid level is sensed, respectively.

Abstract: Method and apparatus for use in measuring SAR (Specific Absorption Rate) of persons subject to RF (radio frequency) radiation utilizes twin well calorimetry including first and second gradient-layer type calorimetry boxes the thermally conductive walls and cover of which contain a multiplicity of thermocouples the outputs of which are differentially amplified to provide a differential output. Identical body models that are thermally responsive to RF radiation are contained in the box wells and, after a period of thermal equalization outside the influence of the RF source, one body model is removed from its well and placed in the influence of the radiation in question while the other remains outside the influence. After a predetermined time period the irradiated model is returned to its well and the differential outputs is plotted over a time period. The area under the resultant curve is representative of total absorption from which can readily be calculated SAR.

Abstract: Measurement accuracy of an oscilloscope is extended by monitoring the temperature within the oscilloscope, and automatically entering a calibration cycle if the temperature varies by a predetermined amount. A temperature sensor is strategically located within the oscilloscope to sense variations in temperature. A first sensed temperature value is stored. Upper and lower temperature limits representing the maximum permissible deviation from the stored value are calculated. Instantaneous temperature values from the sensor are compared with the stored value, and as long as the instaneous values are with the limits, an indication of extended accuracy is provided. If the instantaneous temperature values vary outside the limits, an automatic calibration cycle is initiated. After calibration, a new temperature value is stored and the monitoring process continues to ensure extended accuracy.

Abstract: Disclosed is an apparatus and method for sensing power in a variable frequency machine. The power is sensed in each phase of the three phase machine by utilizing Hall generators for multiplying the phase current flowing through each phase by a current proportional to a phase voltage for each phase. The products are then summed to obtain a reading of the instantaneous power drawn by the three phase machine. The AC component is filtered out of the summed signal using a multi-stage filter which allows for maintaining of a fast response time with low ripple. In a preferred embodiment, a four stage filter utilizing R.C. filters is employed for this purpose.

Abstract: A magnetic sensor for measuring the helix current of a traveling wave tube (TWT). The sensor includes a helix current sense inductor and a reference inductor. The sense inductor includes windings for receiving the cathode and collector currents of the TWT and for receiving a bias current, and also a sense winding. The cathode and collector currents cause permeability of the core to vary in proportion to the difference between those currents, which is equal to the helix current. The bias current is supplied to the bias winding to compensate the sense inductor for temperature-related permeability variations. The bias current is supplied by the reference inductor which is selected to have magnetic properties which match those of the sense inductor. A plurality of sense inductors in conjunction with one common reference inductor may be used for sensing the respective helix currents in the TWTs in a multi-TWT array.

Abstract: A humidity detector includes a first heat-sensing element for an electric signal corresponding to the temperature of steam to be detected and a second heat-sensing element for an atmosphere temperature whose vapor is to be detected or a temperature close to it. A comparator compares the electric signals from the first and second heat-sensing elements. The vapor detection characteristics may be adjusted through variation in the heating temperature of the first heat-sensing element.

Abstract: A femtoammeter is disclosed which resists noise induced reversed bias of the ammeter amplifier and avoids long time constant recovery with unusually high measurement accuracy. The amplifier ammeter has a feedback loop which is provided with paired opposingly faced log diodes in parallel across the feedback circuit. Transients of negative or positive bias are accommodated without biasing the amplifier to a reverse polarity and having unacceptably long time constant recovery. Conventional temperature compensation, not possible with the parallel reversed diode configuration, is supplied by heat sinking the ammeter components, providing a log diode temperature sensor for the heat sinked components and controlling the heat sink operating temperature with a thermoelectric cooler. The temperature sensing log diodes output to a computer lookup table. The same temperature sensing log diode outputs to a bridge circuit operating the thermoelectric cooler.

Abstract: A magneto-optical current sensor for measuring current flowing through a conductor, characterized by at least two components. One component is parallel to the direction of current flow and is proximate to a source of magnetic field. The other component is perpendicular to that direction and includes a surface in contact with said one component. One of the components having a reflective surface for reflecting a polarized light beam between components whereby a light signal is produced that is compensated for temperature, loop degradation, and linearity.

Abstract: Apparatus for measuring current in a conductor characterized by a magneto-optical current sensor employing the Faraday effect to measure current in a high voltage transmission line. Polarized light having a predetermined plane of polarization is directed into the sensor which plane of polarization is rotated by magnetic field lines generated by the current in the conductor. A bimetal coil rotates the sensor to achieve temperature stability of the current signal in the temperature range of -40.degree. C. to 140.degree. C.

Abstract: Passage of current through a power transmission line causes infrared radiation therefrom. The construction of a high-tension (HT) line with counterwound helical conductors for current around a supporting core minimizes the surrounding magnetic field, reducing the skin resistance of the line per unit length as compared to its bulk resistance per unit length. Infrared radiation from the I.sup.2 R losses in the line is thus linearized, and the current in the line can be indirectly measured by sensing the infrared radiation from the line itself using infrared detectors.

Abstract: A system for measuring currents flowing through a conductor uses the current-carrying conductor itself as the measurement shunt. The voltage developed across the inherent resistance of a fixed length of current-carrying conductor is measured and scaled to provide a displayable voltage of magnitude equal to the magnitude of current flowing in the conductor. Compensation for conductor temperature rise can be utilized, as can a multimeter accommodating various conductor materials and/or sizes.

Abstract: An improved system for precisely measuring temperatures at remote locations using a microprocessor and resistance temperature detectors is achieved by providing means for pre-selecting a particular temperature range and using this temperature range information to generate a comparison level for determining the measured temperature. By employing the present invention, the fixed number of bits used to produce the temperature information output is concentrated over a limited range of temperatures, thereby achieving greater precision, since each information bit represents a much smaller number.

Abstract: The invention is directed to an optical fiber device for measuring of current and/or voltage, including at least one light conductor for transmitting optical signals between an optical transducer and light generating and light processing circuitry, respectively. A sensed electrical measuring signal is transmitted to a transducer for conversion to a mechanical movement which modulates the light flux received by the transducer.