Abstract: An intelligent circuit interrupt system is electrically connected between an AC source and a load for interrupting a flow of AC from the source to the load upon detection of an interrupt condition. A circuit interrupter electrically connected to phase and neutral terminals of the AC source defines the interrupt condition. A relay switch with a relay coil and phase and neutral contacts is included such that line and load ends of the phase contact are electrically connected, respectively, between the interrupt means load side phase port and a phase terminal of the load. Line and load ends of the neutral contact are electrically connected, respectively, between the interrupt neutral port and a neutral terminal of the load. The relay coil is electrically coupled between load sides of said phase and neutral contacts for controlling the contacts in response to the interrupt signal.

Abstract: A system and method of protection against the passive loss of differential current fault protection is provided for an electric power generating system (EPGS). The EPGS utilizes a bus power control unit (BPCU) to control and protect bus configuration, and a generator control unit to control each of the generators. This system and method protection protects against perpetuation of a bus fault on a left air vehicle distribution bus, a right air vehicle distribution bus, or a air vehicle tie bus during passive loss of normal differential current fault protection within the BPCU, and comprises circuitry for monitoring parameters of the generator output power, circuitry responsive to these parameters for detecting a high generator current condition for generating an output overload signal when the parameters indicate the presence of a bus fault.

Abstract: A semiconductor device has a protective circuitry including a common discharge line, a first protective device connected between one of input/output terminals and the discharge line, and a second protective device connected between one of Vcc and ground terminals and the discharge line. The second protective device has an on-resistance as much as 1/2 of the on-resistance of the first protective device. Each of the power terminals and ground terminals generally has a large capacitance to accumulate a large amount of electric charge during a CDM test after charging of the semiconductor device as a whole. The low on-resistance prevents the inner circuit and input/output buffers of the semiconductor device from being applied with a higher potential during subsequent grounding of the semiconductor device in the CDM test.

Abstract: In order to obtain an improved operating behavior in the event of short circuits on a high-voltage line having a phase shifter, the phase shifter is used as a current limiter in the event of a fault. A fault signal, which results in an increase in an opposing voltage at an additional transformer of the phase shifter, is produced for this purpose, as a function of a fault current.

Abstract: A novel line-current protection circuit that is useable with a PCMCIA modem card is disclosed. The protection circuit is adapted to detect when an excessive voltage is present across the tip and the ring leads of a telephone subscriber loop by sensing the amount of line-current being supplied to line interface circuitry disposed on the PCMCIA modem card. The protection circuit includes a current sensing circuit portion that is placed in series with the tip lead and which detects when the line current exceeds a predetermined maximum amount. In the event the line current exceeds the maximum amount, the current sensing circuit asserts an excessive line current signal which is being monitored by a digital processor. The digital processor responds by causing a relay circuit to be opened, thereby causing the PCMCIA modem to be in an "on-hook" state.

Abstract: A short circuit protection circuit which has a first short circuit protection circuit in parallel with a second short circuit protection circuit is disclosed. The first short circuit protection circuit includes a sense resistor and a comparator for detecting the short circuit, and a transistor and current source for turning off the low side driver when the short circuit is detected. The second short circuit protection circuit includes a current mirror, zener diode, transistor, and current source connected in series. The second short circuit protection circuit is in parallel with the first short circuit protection circuit. The second short circuit protection circuit accelerates the turn-off of the low-side driver with out affecting the stability of the circuit.

Abstract: A single circuit-breaker is provided in the phase conductor, and the bridging circuit is provided on the load side of the single circuit-breaker, and a magnetically driven switching contact closes a bridging current branch leading to the neutral conductor. The bridging circuit conducts a part of the short-circuit current past the magnetic drive and/or the switching contact. A resistor whose resistance value amounts to between 25 and 50% of the value of the smallest load-circuit impedance (L.sub.2, R.sub.2) to be expected, may be provided in the bridging current branch. In such an arrangement, the bridging circuit and the circuit-breaker can form one unit.

Abstract: An overcurrent protection system which will give a rapid response to relatively small overcurrents. The system, which can be connected between an electrical power supply and an electrical load to form an operating circuit, and which when so connected protects the circuit from overcurrents, has a normal operating condition and a fault condition, and comprises: a circuit interruption element having, (1) a normal state which permits the flow of a normal current, I.sub.NORMAL, when the system is in the normal operating condition, and (2) a fault state which permits the flow of at most a reduced current, substantially less than I.sub.NORMAL, when the system is in the fault condition; and a control element, connected in series with the circuit interruption element, the control element having a variable resistance which (1) is low when the current in the system does not exceed the normal current, I.sub.

Abstract: A signal input unit for a semiconductor memory device comprising a signal input terminal, an electrostatic discharge protection circuit for discharging an electrostatic signal of high level from the input terminal to a ground voltage source, a signal transfer circuit connected in parallel to the electrostatic discharge protection circuit, for switching a normal input signal from the input terminal, a signal transfer control circuit for controlling a switching operation of the signal transfer circuit, and a signal input circuit for buffering an output signal from the electrostatic discharge protection circuit or the signal transfer circuit and transferring the buffered signal to an internal circuit of the semiconductor memory device. The electrostatic discharge protection circuit sufficiently discharges the external electrostatic signal to the ground voltage source in a standby mode of the semiconductor memory device.

Abstract: A modular electrical assembly including a plurality of conductive electrical components aligned in a column along an axis and electrically connected at axially directed ends. First and second conductive end members are located at opposite sides of the column, the end members having shoulders extending radially relative to the axis, each shoulder having an outer surface facing radially outwards. A non-conductive winding is wrapped in a predetermined pattern about the electrical components and the end members, engaging the shoulders, and applying an axially directed compressive force through the shoulders on the electrical components and end members to maintain electrical connection therebetween. A housing encompasses the winding, while a strip, located between the housing and the winding, covers the outer surface of the first end member to protect the housing from contact with the outer surface of the shoulders. The strip also covers voids between the first end member and the non-conductive winding.

Abstract: An in-line cord ground fault circuit interrupter which contains within a common housing the sensing unit and the tripping relay usually found separately packaged at a remote location. The fixed contacts are mounted on fixed contact arms mounted adjacent one surface of a printed circuit board with the movable contacts mounted on movable contact arms mounted adjacent the second surface. The tripping relay operates an armature between an open and a closed condition and by cams on the arms of the armature opens and closes the movable contacts with the fixed contacts. The two portion housing allows the components of the interrupter to be mounted on one portion of the housing which also supports the line and load conductors making assembly of the rear housing portion to the front housing portion easy.

Abstract: A circuit senses an insertion of an adapter card into a connector coupled to a processor by an MCA bus and signals control logic, which forces all other adapter cards coupled to the MCA bus off of the bus with a preempt signal, driving the bus into an arbitration mode. This may be done while the system is powered. An analog switch divides the preempt signal into one that goes to the adapter cards and a second one that is sent to the processor so that it can perform memory refresh cycles.

Abstract: A protection system for an electric motor is disclosed. The system is adapted for providing protection to the motor in the event of a stall or reduced-speed condition. The system includes a sensor providing a first signal representative of the speed of the motor, a detection circuit receiving the first signal and providing a second signal indicative of whether the motor is in a stall or reduced-speed condition, and a switching circuit receiving the second signal and interrupting power supply to the motor when the second signal indicates that the motor is in the stall or reduced-speed condition.

Abstract: A protection circuit for use with a hot water dispensing apparatus of the type which includes a reservoir and a heating element coupled to the reservoir for heating water retained therein. The protection circuit includes a conductivity detector coupled to the reservoir for detecting a desired quantity of water in the reservoir. A first sensor and a second sensor of the conductivity detector are coupled to the reservoir at spaced apart locations. A conductivity detector circuit is coupled to the first and second sensors and coupled to a control circuit of the hot water dispensing apparatus for preventing operation of the apparatus until a desired quantity of water is disposed in the reservoir.

Abstract: A small-sized arrangement for a DC circuit breaker with a reactor and a capacitor connected in series is provided which includes a DC circuit breaker, a parallel impedance means with a suitably determined inductance and a suitable capacitance less in value than the inductance, and an energy-absorbing element. The parallel impedance means has a parallel reactor of a carefully selected inductance and a parallel capacitor of a smaller capacitance value. Determining the inductance and capacitance values of the parallel reactors and parallel capacitors employed in the parallel impedance means to satisfy a certain condition defined by specific formulas can cause the DC circuit breaker to take full advantage of the inherent performance thereof while allowing the interruption time to remain minimized, thereby achieving enhanced interruption performance. Since the capacitance of the parallel capacitor is rendered relatively smaller, the device can be small in size and low in cost.

Abstract: An electrical apparatus (100) line actuator (102), such as a voltage regulator or circuit breaker, has resident therein a personality module, electronically reconfigurable memory device (126) which stores actuator operational information, such as specifications (132), historical and maintenance information. An apparatus controller (106) communicates with the personality module (126) and can change the operational information stored therein. If either or both of the controller (106) and actuator (102) is replaced at a site, the controller (106) of the replacement apparatus configuration (100) can read the operational information stored in the personality module (126) and adapt its operational interaction with the actuator (102) in conformance with the information.

Abstract: A protective shield adapted to be clamped to an electrical hot stick of the type used for performing electrical work on various types of energized electrical equipment. The protective shield includes a transparent plate formed of an impact resistant plastic material and a clamping mechanism for securing the plate to a hot stick. An opening in the plate allows for passage of the hot stick through the plate, afterwhich a pivotally mounted clamp arm and bolt arm are secured together about the hot stick. The protective shield provides physical protection to linemen working in live-line or deenergized maintenance situations by acting as a barrier between the lineman and the equipment while providing complete visibility to the task being performed.

Abstract: An improved line arrester is disclosed that includes a non-linear resistor. The arrester includes a pair of arcing horns are respectively provided on an earth side and a line side of the arrester, with an aerial discharge gap being provided therebetween. The aerial discharge gap is in electrical parallel with the resistor. The length of the aerial discharge gap is selected such that flashover does not occur in response to currents smaller than a rated discharge current of the resistor, yet flashover does occur in response to a current that is greater than the rated discharge current, but lower than a critical discharge current of the resistor. With this arrangement the resistor is protected against the lightning surge current greater than the critical discharge current.

Abstract: A ground fault circuit interrupter (GFCI) line cord plug utilizes an electronically latched relay, rather than a circuit breaker or other type of mechanical latching device, to interrupt the AC load power when a ground fault condition occurs. In order to reduce the size of the relay and minimize the cost and complexity of the GFCI plug, the fixed and movable relay contact structures are mounted directly to the circuit board which carries the remaining components of the GFCI circuit. In a preferred embodiment, the fixed relay contact structures are integral with the plug blades of the GFCI plug. The movable relay contact structures preferably comprise deflectable spring arms which are preloaded when the relay contacts are in the open position in order to control the contact gap, and which are deflected past the point of contact closure when the relay contacts are in the closed position in order to increase the closing force.

Abstract: A motor controller unit that employs standard motor contactors and electronic circuit breakers includes an electronic control module (ECM) for interfacing with the contactors and circuit breakers. Electrical connection with the circuit breaker electronic trip unit and the ECM is made by means of the circuit breaker rating plug. Electrical connection with the contactors and the ECM is made by means of externally-accessible terminal screws.