The present invention is a component monitoring system which includes all sensor and plant component monitoring at distributed plant locations close to the sensors which are the source of the signals to be analyzed. Minimally preconditioned analog sensor signals are multiplexed and further conditioned by a sensor signal preprocessor that adjusts the gain and filters the sensor signals before being applied to an analog-to-digital converter controlled by a data acquisition computer. The analog sensor signals are converted into digital samples and stored in a data memory of a digital signal processor using a direct memory access technique. The data acquisition computer also controls the selection of sensors, gain, etc., based on commands from a controller. The digital signal processor, once sufficient sensor data has been collected, performs appropriate processing using known digital signal processing techniques. This processed data is then sent to the controller for analysis to determine plant component condition. The analysis and processing routines can be changed by downloading a new routine from the controller. Once a sensor signal is processed, the controller selects the next sensor by transmitting an appropriate command to the data acquisition computer.

Smart sensor system for diagnostic monitoring

A data processing system is provided for identifying risks associated with abnormal conditions of network elements in a communications network. A data collection and processing module collects alarm message signals from a communications network and processes the alarm messages to general abnormal condition signals. An interface module also receives external condition signals indicative of external conditions affecting network elements in the communications network. The system provides an electronic risk processing module that generates direct and indirect risk signals based upon the abnormal condition signals, the external condition signals, and stored reference data. A display means displays a network element risk signal which is the sum of said direct and indirect risk signals. The displayed risk signal aids in assessing risks associated with network elements experiencing abnormal conditions. The system also generates and displays a sub-network risk signal. The system also adjusts the various risk calculations to take into account different types of planned maintenance activities.

Network vulnerability management apparatus and method

Improving reducing or eliminating the effects of variation in characteristics of the resonance circuit in a resonance type displacement detection apparatus, so as to improve displacement detection accuracy. In a displacement detection system 10 , the resonance frequency range assumable by the resonance circuit 21 is estimated in advance, there is determined a drive frequency variation range f 1 -f 2 such that the estimated resonance frequency range is included therein, and by means of a variable oscillator 30 , drive frequency is repeatedly varied between the first frequency f 1 and the second frequency f 2 . Accordingly, where the resonance frequency of the resonance circuit 21 is fr 1 , when the drive frequency has changed to fr 1 , resonance voltage Vgl 1 may be obtained in the case of large gap G. Where the resonance frequency of the resonance circuit 21 is fr 2 , when the drive frequency has changed to fr 2 , resonance voltage Vgl 2 may be obtained in the case of large gap G.

Displacement detection apparatus and displacement detection method

The method monitors switches in an isolated circuit mounted on a turning component of the car, e.g. steering wheel or column. The circuit is fed by a phase transformer with a.c. through its windings which are connected, on the one hand to the car and, on the other hand, to the turning component. The primary winding receives a driving voltage fromm the car's power source. In the isolated circuit there is a capacitative and an inductive element - and the latter, at least in part, can be supplied by the sec. winding- forming a resonant sub-circuit, with a resistance to limit the current. When at least one of the switches is activated, the resonance behaviour of the sub-circuit changes from the case when none is being activated and a comparison of the voltages and currents flowing can be used to monitor the switches. Other electronic unis are provided to analyse the results. ADVANTAGE - Requires only few components which need not themselves be precision types.

Wireless interrogation and current supply method for switches - using capacitative and inductive elements corresp. to sec. winding of transformer

Paging system comprising a transmitter and one or more paging receivers, where said transmitter may transmit a communication comprising a first data block to all receivers. Each receiver comprises a first memory comprising up to five registers for storing therein component data blocks of said first data block, of which a second component representing a receiver address or select code in register, a third component, possibly composed of fifth and sixth subcomponents representing a message code and a message identification code in registers respectively, a fourth component representing a control code in register, and a seventh component representing an alternative message identification code in register 18. In a second memory of said receiver a plurality of third data blocks may be stored in a corresponding plurality of memory locations, the message code in which may be displayed and each of which may be erased if, depending on the value of the control code, the message code and/or the identification code thereof in first memory is identical to the corresponding contents of the location, which, in case of equality, may be written then with a new third data block, of which the message identification code may be the alternative message identification code.

Paging receiver and transmitting device adapted to said receiver

A safety system (10) for shutting down a nuclear reactor under overload conditions is provided using a series of parallel-connected computer memory type look-up tables (14a, 14b, 14c, 14d, 14e) each of which receives data on a particular reactor parameter (P, T, φT, φB, W) and each of which has stored therein a precalculated functional value [f(P); f(T); F(φT); f(φB); f(W)] for that parameter indicative of the percentage of maximum reactor load that the parameter contributes. The various functional values [f(P); f(T); f(φT); f(φB); f(W)] corresponding to the actual measured parameters are added together to provide a control signal (S) used to shut down the reactor under overload conditions.

Nuclear reactor safety system

@ A passive multiplexer for processing a plurality of conditions in a harsh environment comprises a transmission line (12) having a measurable impedance characteristic. A plurality of crystals (31 - 33) are coupled to the transmission line (12), each crystal having a different resonant frequency. Each crystal (31-33) has a first impedance when excited by its resonant frequency and a second impedance when not excited by its resonant frequency. A switch or other transducer (34-36) is connected to each crystal (31-33) or between each crystal and the transmission line (12) for selectively connecting or disconnecting the crystal, or otherwise influencing the impedance of the crystal in response to each condition of interest in the harsh environment (10). A frequency sweep generator (56) is connected to the transmission line (12) for supplying the line with a range of frequencies within which all of the resonant frequencies lie, so that each of the crystals (31-33) can be excited. A detector (58) is connected to the transmission line (12) for detecting changes in its impedance which results from impedance influence of the crystal (31-33) on the line depending on whether the transducer (34-36)has connected or otherwise effected the crystal and whether the crystal is being excited by its resonant frequency.

Multiplexers and methods of measuring conditions in harsh environments

A system for monitoring a limited number of operating conditions in a nuclear reactor and for graphically displaying same on a display device is disclosed. The system parameters selected are those which typically change as a result of a reactor trip. As long as these system parameters remain within a "post-trip window" on the graphic display, the power plant is operating normally. If, however, any of the foregoing system parameters falls outside this "window", this is an immediate indication to the power plant operator to institute the necessary procedures to remedy same. A sequential controller (26) is provided to continuously sequentially sample the foregoing operating parameters and to transmit data regarding same to the display device.

Robert C. Roberts

Papers

Nuclear reactor safety system

Multiplexers and methods of measuring conditions in harsh environments

Electrical circuit for providing an abnormal transient display system for nuclear reactor operation

Sicherheitssystem fuer einen kernreaktor