Abstract: In a pump drive circuit, a power source voltage signal supplied to the pump is phase-controlled by a triac connected between the pump and the power source. The period of triggering the triac is determined by a time constant circuit of a UJT, a capacitor and a resistor circuit. The power source voltage signal has its frequency determined by a frequency discrimination circuit. The resistance value of the resistor circuit is selected in accordance with the result of the discrimination. Accordingly, the pump is applied with a voltage signal the phase of which is controlled in accordance with the power source frequency, and is thus driven to maintain a predetermined output.

Abstract: A system for gating a computer to receive navigational information from the osition sensors of the periscope assembly of a submarine is disclosed. A first coil is connected as the load coil of an oscillator and is mounted in a stationary position on a submarine bulkhead. A second coil is secured to the periscope assembly and moves up and down with the periscope, in and out of magnetic coupling with the first coil. A third coil is secured to the periscope assembly and moves up and down with the periscope assembly. A fourth coil is secured to the rotatable periscope assembly and remains magnetically coupled to the third coil while the periscope is either rotated or moved up and down. A normally opened switch button on the periscope handle is electrically connected to the fourth coil. Depression of the switch button results in a load on the oscillator which is otherwise normally tuned to the same frequency as a second oscillator.

Abstract: The present invention relates to a power sequence device which comprises an element which generates a sequencing code which is capable of being decoded by actuators included in the various equipment cabinets. The sequencing code is initiated by a sensing element which indicates the input power has reached a stable threshold whereupon the various cabinets comprising the data processing system are turned on in a desired order. Upon loss of power, the sensing element generates a warning signal indicating an impending power loss thereby enabling the equipment to perform an orderly halt.

Abstract: Information is conveyed from a transmitting site to a consuming location in an electric power system by varying the frequency of the power from the nominal standard generating frequency. The signaled variation in frequency is detected at a power consuming location and a frequency indicating signal is generated. Frequency deviations of predetermined magnitude for a predetermined time duration signal a selected range of power system load while different deviations for different times signal automatic remote control of certain predetermined loads or other functions.

Abstract: A fuel burner control system is disclosed which uses a frequency sensitive diode pump circuit fed by a series of input pulses having a repetition rate within a predetermined range. The diode pump circuit produces an output having a direct current component which exceeds a predetermined threshold when the repetition rate of the input pulses is within a predetermined range. A comparator circuit delivers a pulse signal to a fuel control device when the direct current component exceeds a predetermined threshold.

Abstract: Two gas turbine power plants are started and accelerated by fuel controls on selection of dead load mode. The startup is coordinated so that one turbine-generator is controlled as the lead unit and it is driven to a speed higher than normal, short of overspeed condition at which time its breaker is closed on an auxiliary bus. Shortly thereafter the second turbine-generator is synchronized to the first and its generator breaker is closed to the auxiliary bus. The two units are then ready for a simultaneous 200% load pickup from the dead load bus. After the load is applied, the lead unit is placed under isochronous control and the follow unit is tracked to the lead unit. Turbine lead/follow roles can be reversed during startup under certain conditions, and predetermined data is exchanged between the controls to enable coordinated dead load pickup operation.

Abstract: Spurious subsynchronous and supersynchronous electrical signals in an electrical power system are detected rapidly and reliably by generating an electrical signal which is proportional to the power signal and rectifying the generated signal. The rectified signal includes a dc component and a component having a frequency equal to the difference of the contact power frequency and the spurious signal frequency. The component is readily identified by a tuned filter and detector whereby remedial action can be taken to eliminate the spurious signal.

Abstract: A frequency adaptive, power-energy re-scheduler (FAPER) that includes a frequency transducer that notes frequency or frequency deviations of an electrical system and logic means which controls and re-schedules power flow to a load unit in part on the basis of the deviations in frequency from a nominal frequency and in part on the needs to the load unit as expressed by an external sensor signal obtained from the physical system affected by the load unit.

Abstract: Information is conveyed from a generating site to a consuming location in an electric power system by varying the frequency of the power from the nominal standard generating frequency. The signaled variation in frequency is detected at a power controlling or consuming location and a frequency indicating signal is generated. Frequency deviations of predetermined magnitude for predetermined time duration signal a selected range of power system load while different deviations for different times signal automatic remote control of certain predetermined loads or other functions.

Abstract: Energy management method and apparatus for use in conjunction with a demand-limited alternating current circuit having a plurality of separate loads, including resistive loads, and means for automatically shedding certain of the loads when the actual demand of the circuit exceeds the demand limit. The actual demands of the loads in operation are sensed and the demands of at least certain of the operative resistive loads are separately sensed. The duty cycle of the power applied to at least certain of the operative resistive loads is reduced by switching these loads "off" and "on" synchronously with the zero points of the applied voltage. An overall reduction in the actual demand of the circuit is thereby effected when the failure to make such reduction would otherwise cause certain of the operating loads to be completely shed.

Abstract: A safety circuit for protective operation at the interface between certain customer premises telephone installations and the external telephone distribution lines. The protection circuit includes a means for discriminating any voltages of sufficient magnitude having a frequency at or near 60 Hz., and upon such detection, a reactance means is responsive to open the connection between the premises telephone installation and the external telephone distribution line.

Abstract: An energy conservation system is disclosed wherein power in a given area, such as in a hotel or other room, is controlled by means of an ultrasonic sound transmitter and at least one or more ultrasonic sound receivers, each receiver controlling power for a separate power outlet. Upon entering the room, a key is inserted into a key receptacle to change the operating state of the transmitter, to thereby cause the receivers to couple power to the power outlets in the room. When the key is withdrawn from the key receptacle, the transmitter operating state is changed again, to cause the receivers to decouple power from their respective associated power outlets. The system can also incorporate temperature compensation means to control minimum or maximum temperatures in the area. The system can further accommodate intrusion, fire and occupancy detection signals as additional features.

Abstract: A circuit arrangement for a remote control receiver, especially a ripple control receiver, which receives remote control signals from a power mains, comprising means for reducing the ambiguity of the response characteristic of the remote control receiver caused by at least one non-linear circuit element connected with the input of a selective receiver section of the remote control receiver.

Abstract: Apparatus for detecting the presence of subsynchronous current components in an electrical generating or transmission system is disclosed. Input signals, representative respectively of line voltage and current, are conditioned and initially filtered to suppress high frequency noise. The input voltage signal is further limited and filtered to produce a constant amplitude, sinusoid reference. The input signals are then multiplied to yield the subsynchronous current signal components, if any, which undergo further filtration by a bandpass filter circuit. In addition, the detection apparatus is provided with circuit means for insuring protection against overvoltage and current surge conditions.

Abstract: A digitally synthesized frequency back-up circuit which, after removal or failure of applied A.C. power, will reproduce signals precisely indicative of each zero transition point of the A.C. waveform. A high frequency binary counter continually counts internally generated pulses and at the end of each A.C. period, stores one-half the count, representing 180.degree. , in a storage buffer. When the A.C. fails, the inverted value of the buffer count is loaded into the counter which is incremented by the internally generated pulses to count only up to the value stored in the buffer, at which point the circuit generates an output pulse. As long as the A.C. frequency remains off, the counter will continue to reload from the buffer and count the value representing this 180.degree. period. An additional and separate buffer section in the circuit stores the binary count representing the 90.degree. point in each A.C. cycle and continuously generates 90.degree.

Abstract: A frequency responsive switching circuit that, in the preferred form, includes circuit means for generating a periodic first electrical signal. The first electrical signal is applied to a retriggerable monostable multivibrator having as its output a second electrical signal. A timing circuit associated with the retriggerable monostable multivibrator controls the duration of the output pulses constituting the second electrical signal. If the period of the first electrical signal is less than a predetermined amount, the second electrical signal is maintained at a fixed voltage level due to continuous retriggering of the multivibrator. The second electrical signal is applied to the data input of a shift register and the first electrical signal is supplied to the shift register as a trigger input. Multiple bit outputs of the shift register form the inputs to a gate circuit.

Abstract: An energy conservation system is disclosed wherein power in a given area, such as in a hotel or other room, is controlled by means of an ultrasonic sound transmitter and a plurality of ultrasonic sound receivers, each receiver controlling power for a separate power outlet. Upon entering the room, a key is inserted into a key receptacle to activate the transmitter and thereby cause the receivers to couple power to the power outlets in the room. When the key is withdrawn from the key receptacle, the transmitter signals the receivers to decouple power from the power outlets.

Abstract: Disclosed is a switching arrangement operable by a tone of a predetermined frequency. An automatic gain control amplifier has an input connectable to a source of signals and an output connected to an input of a bandpass filter which rejects all frequencies except those of a narrow band centered on the predetermined frequency. The bandpass filter is connected to an input of a phase locked loop which produces a change in voltage from a first level to a second level at its output only in response to a narrow band of frequencies centered on the predetermined frequency. The output of the phase locked loop is connected to a timer which only produces a pulse at its output upon receipt of the second level of voltage for a predetermined time. A pulse from the timer is fed to a flip-flop which changes state and operates a relay.

Abstract: A remote switch control system of the type responsive to sound control waves suitable for use with electric appliances. The switch or receiver unit is built in a housing having a power inlet of the type of a regular electric plug so that the housing can be fixedly secured to an electric socket. The power outlet of the housing is of the type of a regular electric socket for receiving the household appliance power cord plug. Thus, the device can be used with any household appliance or the like. The circuitry of the receiver includes a flip-flop used as switch actuating means.

Abstract: A relay for detecting sustained subsynchronous current on a power system. The relay includes a filter network for separating subsynchronous current from synchronous current and a detector network for measuring the detected subsynchronous current.

Abstract: An electronic control actuating system having signal transmitting or injector means and signal receiving means. The signal transmitting means includes a plurality of self-contained oscillator circuits, each oscillator circuit capable of producing an independent radio frequency output signal and wherein the oscillating circuits are adapted to be selectively positioned relative to an actuator means capable of sequentially supplying energy to each of the oscillator circuits for effecting an output of a plurality of sequentially transmitted coded signals.