Abstract: A two-way data communication system using a plurality of CPUs is provided with at least one CPU which detects abnormalities in the operation of further CPUs and accordingly cuts the power to and resets an erroneously operating CPU.

Abstract: In a system including an electrical power center for producing and distributing electrical energy for vehicles, particularly aircraft, primary circuit breakers and contactors are distributed between a D.C. electrical power center, relay boxes, electronic bays and control panels and the electrical power center forms a central unit grouping together different protection or safety devices. The system permits the electrical network on board an aircraft to be simplified and lightened.

Abstract: An inductor generator for welding in which: a plurality of generator elements are combined and incorporated in a single generator and respectively provided with excitation windings to render the generator elements self excitable; a constant-current control circuit is inserted between each excitation winding and corresponding field winding in order to stabilize the field current which has been once set. The constant-current control circuits are so mutually connected that compensation operation is possible so that, when the field current of any of the generator elements is varied, fluctuations of the output values of the other generator elements are prevented, these fluctuations otherwise being due to various effects acting mutually between the generator elements, particularly magnetic effect, in spite of the fact that the field currents of the other generator elements are being maintained at their set values. As a result the above described problems of the prior art are overcome.

Abstract: A reference branch circuit includes a voltage divider. Each of at least one regulated branch circuits includes the collector-emitter circuit of a regulating transistor and a measuring resistance. Each regulated branch circuit is associated with a comparator, which compares voltage across the measuring resistance of the corresponding regulated branch circuit to a reference voltage appearing at a reference tap of the voltage divider in the reference branch circuit. Current passing through each regulated branch circuit is regulated to be equal to the current flowing through the reference branch circuit.

Abstract: A stabilization circuit is provided for use with a ferroresonant power supply to maintain a steady output voltage during power line transients, rapid load changes, or no load condition. The stabilization circuit is responsive to the voltage output of the power supply and selectively connects a load across voltage output terminals. Stabilization circuit includes a voltage sensing circuit that enables a timing circuit that activates a switch to place the load across terminals. This stabilizes the power supply, without requiring a continuously dissipative minimum load.

Abstract: The variable impedance circuit comprising the invention provides a circuit having an impedance which varies in response to an input signal. The invention utilizes a control circuit which samples the load current and compares it to the demand signal to generate a control signal. The control signal is coupled to a load driver circuit to cause the required current to flow through this circuit. The load driver circuit and one or more substantially identical load circuits are series coupled to form a variable impedance circuit having the desired voltage and current capability.

Abstract: An energy conserving thermostatic control system having digitally implemented control functions for use with a heating and/or air conditioning system is disclosed. The digital thermostat includes an LCD data display for simultaneously displaying present time and ambient temperature. Slide switches are provided for setting and indicating set point information such as day temperature, night temperature, night-to-day transition time, and day-to-night transition time. The switch contacts of each slide switch are multiplexed to the display driver conductors for conveying time and temperature set point data during time and temperature scan intervals which alternate with a display interval. Strobe signals which are applied to the driver conductors are counted during the alternate scan intervals for selecting a day temperature different from a night temperature, for selecting the times which divide night from day and for providing set-back to night temperature during a predetermined time of the day.

Abstract: The generation of internal circuit noise due to the switching of differing numbers of bilevel data lines is suppressed by maintaining the energizing current substantially constant with widely varying amounts of current drawn by varying the current drawn by redundant driver circuits, which also generate parity or check signals, to compensate for the difference in current drawn by the designated data driver circuits. The number of redundant driver circuits is reduced by loading the second and further redundant driver circuits for drawing currewnts related to the current drawn by the first redundant driver circuit by succeeding powers of two. Further suppression in internal circuit noise obtains with gating of all driver circuits at the time switching occurs. Control circuitry comprising conventional full adder circuits arranged for expressing the number of data signal lines in a given level is advantageous for controlling the redundant driver circuits and for generating check bits at the same time.

Abstract: A half-wave and a full-wave rectifier using transistors as rectifying elements have independently controlled multiple output voltages obtained from a single power supply. The transistor used as a rectifying element has its turn-on controlled thus allowing voltage control by phase control action.

Abstract: A regulating transistor is connected between a constant current load and a constant voltage load. A control circuit responds to voltage variations of the constant voltage load to adjust the transistor whereby a constant current and a constant voltage and supplied to both loads. In a vidicon camera circuit a focusing coil presents a constant current load and a heater element presents a constant voltage load.

Abstract: A plurality of modules, each adapted to generate repetitive RF pulses are connected to a common coarse DC power supply. Each of the modules, which include a pulsed load, has a switching transistor connected in series with the load, and a precise voltage connected to its base to regulate the voltage during each of the individual pulses. A capacitor may be connected in each of the modules for improving the rise time of the individual pulses.

Abstract: In a power circuit arrangement, there are a plurality of voltage stabilizers each including a reference voltage source, a circuit for comparing the output of the respective voltage stabilizer with a reference voltage, and a voltage control element responsive to the output of the comparing circuit. The reference voltage for at least one of the voltage stabilizers is provided by an independent element, and the reference voltage for the remaining voltage stabilizers is formed on the basis of the output voltage of the other voltage stabilizers. When the output voltage of any one of the voltage stabilizers becomes zero, all of the other voltage stabilizers similarly have their output voltages reduced to zero.

Abstract: In an electrical load control system, an analog signal representing the actual rate of power being consumed by a plurality of loads has a nominal level when the actual rate is at a desired rate, or set point. As the level of the analog signal deviates from its nominal level, the electrical load control system functions to add or shed one or more of the loads to maintain the actual rate at the set point. During times of low power consumption, the electrical load control system may not act to optimize energy usage if the set point is not lowered. A set point control circuit is provided which senses the on/off status of one of the loads, or control load, and which provides a set point modification signal whose level represents a desired reduction in the set point and which varies in a predetermined range between minimum and maximum levels representing, respectively, no reduction in the set point and a maximum reduction in the set point.

Abstract: A time division switching regulator wherein a single power source is connected to a plurality of inverters the outputs from which are rectified and smoothed and appear at respective output terminals, and the output voltages at said terminals are sequentially monitored and are compared with a reference voltage to generate an error signal in response to which the output from the corresponding inverter may be controlled or regulated.

Abstract: A demand controller includes a microprocessor which is programmed to input data from switches on a control panel and output data to a set of eight circuits which control the operation of loads. Peak power demand is maintained below a preset DEMAND OBJECTIVE by selectively shedding these loads. The shed level for each load is not fixed, but instead, varies as a function of the rate at which total power demand is increasing. This rate is calculated by the microprocessor and the resulting shed level index (i) is employed to select the proper shed level for each load from a stored shed level matrix.

Abstract: The control system permits limiting the electrical demand of a distribution network to a desired maximum value by regulating the temperature of one or more thermal loads with heating or cooling elements; this system includes: means for measuring the instantaneous demand of the network; means for measuring the instantaneous temperature of each of the thermal loads; means for comparing the demand of the network to the desired maximum value; means for comparing the measured temperature to the desired temperature for each of the thermal loads; and means for disconnecting or for connecting in response to the information obtained by the comparison, a fraction of the elements which is proportional to the difference between the measured temperature and the desired temperature.

Abstract: A computerized welding control system which is capable of controlling a large number of welding heads from a single processor, the processor being the timing instrumentality for the various portions of the welding cycle. The system also includes standard welding circuitry to control the percent heat and the control of the first electrical cycle of the welding cycle. The system includes a data entry terminal for a set of welders within the group controlled by a single processor, the terminal being capable of addressing the computer to determine the time stored therein for various functions within the welding cycle for a particular machine within the group controlled by the terminal unit. The terminal unit also includes capability of changing the times associated with each portion of the welding cycle.

Abstract: A single-ended dc-to-dc converter which comprises a transformer having a primary winding which is connected to a d-c voltage source via a switch, a secondary winding which is connected to a load via a series valve and a choke, and a remagnetizing winding. In order to obtain an output voltage from the converter which is higher or lower, as desired, than the d-c supply voltage, provision is made for a first controlled by-pass valve to be shunted across the series connection of the secondary winding and the series valve and for a second controlled by-pass valve, poled in the direction of the load current, to be connected in parallel with the series connection of the choke and the load.