Abstract: An adaptable housing for a PC clone computer or the like includes easily removable front and rear panel sections and a cover, all of which are adapted to be conveniently drilled, punched, etc. for internal or external attachment of switches, connectors, and/or other user-installed equipment. A removable card cage resting on a removable base receives a variety of PC boards or other equipment in suitable slots and allows internal routing of cables, conductors, and the like from printed circuit boards mounted in the card cage to slots and/or other printed circuit boards on or connected to a horizontal mother board or back plane attached to the bottom panel of the housing. One or two boxes are attached to the front panel or the bottom panel by means of suitable brackets to carry disk drive units or other equipment.

Abstract: A modular plug-in instrumentation system for enabling a personal computer to perform instrumentation functions, including receiving analog and digital signals from an external device and transmitting analog and digital signals to an external device, includes a carrier module pluggable into a bus of the personal computer, and also includes an internal instrumentation bus into which a plurality of different interchangeable instrument modules can be plugged. The instrumentation bus includes a digital portion, and also includes a segmented analog portion that is extendable merely by plugging instrumentation modules into bus connectors which span gaps between the analog bus segments. Analog and/or digital signals are communicated between various instrument modules and external devices by means of cables connected to the instrument modules.

Abstract: A microprocessor based recloser control has a microcomputer for causing trip and close operations of a recloser in response to the conditions of the power distribution lines being protected and operator commands. The microcomputer may be overridden by a mechanical switch in the recloser control. If power to the recloser control is lost, the microprocessor will continue to function with power storage means for a limited duration. Towards the end of that duration, this microcomputer will power down the microprocessor in an orderly manner allowing automatic return to its functions when power is restored. After the microprocessor is no longer functioning, a secondary overcurrent trip circuit is relied upon to cause a trip operation of the recloser for extended durations of power outage. The secondary overcurrent trip circuit can be disabled by the microprocessor.

Abstract: The power outage timer (36, 136, or 236) forms a part of an electronic watt-hour meter (10) having a microprocessor (22), a real time value memory and a real time clock signal input from a voltage supply (23). The power outage timer (36, 136, or 236) is coupled to the microprocessor (22) for generating a signal when, after a power outage, power is restored, such signal being indicative of the time duration of the power outage and being input to the microprocessor (22) so that the microprocessor (22) can update the real time value in an EAROM (32) to reflect the correct real time.

Abstract: A voltage regulating transformer utilizing a microprocessor and a versatile multipurpose set of hardware modules and software modules it is described. A standard tap changing mechanism is driven in response to an analog control signal to change the output voltage of the transformer in response to digitally sampled values of voltage and current which have been transformed from the time domain to the frequency domain through a software program using Fourier transform techniques. The output current is also transformed and digitally processed to determine the power factor and the direction of power flow through the transformer. By inserting the digital values of the line characteristics to the load, line drop compensation is provided for. The difference in voltage across the input and output transformers is transformed to a digital signal and internally processed to provide an indication of the position of the tap changing mechanism without relying upon mechanical devices.

Abstract: The circuit includes a phase-locked loop that produces pulses a fixed number of engine degrees before the ignition signals. These pulses are used to initiate the horizontal sweep of an oscilloscope that displays the ignition pulses. Accordingly, the ignition signals commence not at the beginning of the display where useful information may be lost, but rather a predetermined number of engine degrees later.

Abstract: A transducer produces a sequence of pulses corresponding to the compressions in the chambers of an internal combustion engine. Gating signals are produced in substantial time coincidence with these compression pulses. A number of channels are coupled in parallel corresponding to the number of chambers of which compression is to be measured. The channels are successively rendered operative by the gating signals which detect the amplitude of the compression pulses, by peak detection or counting clock pulses, for example. An annunciator is coupled to the several channels to express sequentially the information stored therein.