摘要:
A string includes direct current electrical generating modules electrically connected in series to form a first end and a remote second end. A power line is electrically connected to one DC EGM at the first end. A return line is electrically connected to another DC EGM at the remote second end. A first string protector is in the power line of the string, and a second SP is in the return line of the string at the remote second end. One of the first and second SPs includes a number of an over current protector, an arc fault protector, a reverse current protector and a ground fault protector. The other one of the first and second SPs includes a number of an over current protector, an arc fault protector, a reverse current protector, a ground fault protector, and a remotely controlled switch in series with the power or return lines.
摘要:
A battery disconnect includes a housing, battery and load terminals, separable contacts electrically connected between the battery and load terminals, an operating mechanism structured to open and close the contacts, and a manual operator cooperating with the operating mechanism to open and close the contacts. A current sensor is structured to sense current flowing between the battery and load terminals. A circuit cooperates with the current sensor and the operating mechanism to trip open the contacts responsive to arc fault, overload and short circuit conditions associated with the sensed current. The circuit includes a first input structured to receive a remote on/off signal and a second input structured to receive an inhibit signal. The circuit cooperates with the operating mechanism to open and close the contacts responsive to the on/off signal, and to inhibit detection of the arc fault, overload and short circuit conditions responsive to the inhibit signal.
摘要:
A residential or commercial circuit breaker of the narrow case type, typically having a width of 3/4 inch or 1 inch, is provided with a single-piece nonlaminated slot motor 102 mounted within the case 2 and around current carrying conductors 8 and 12 for concentrating magnetic repulsive force and boosting contact separation force. A dramatic increase in short circuit interruption capacity is achieved, at minimal cost.
摘要:
A thermally responsive shape memory effect (SME) element (4) is positioned adjacent a fixed heater (40) for moving away from the heater to a switch actuating "memory" position as current induced temperature increases, thereby establishing changes in heat transfer coefficient between the heater (40) and thermally responsive element (4) for each increment of movement. An intermediate switch actuating lever (22) is carried on a movable range adjustment lever (16) to vary pretravel of an SME driven plunger (12). The SME element is resettable against a fixed stop (2c) for achieving accurate repetitive resetting of the device.
摘要:
A two-bimetal thermostat provides double motion for enhanced contact actuation and minimum differential. Two bimetal plates are pivotally supported at one end to extend generally parallel. The other, deflectable ends of these bimetal plates, one of which is shorter than the other, have right-angle bends and are biased by a compression C-spring for overcenter snap-action. These deflectable ends are coupled by drive pins to respective contacts of a spring-biased contact pair to be free of the bimetal plates when closed and are actuated thereby to open condition. Differential adjustment is accomplished by adjusting one bimetal plate longitudinally to vary the C-spring load thereby to correspondingly vary the temperature differential between contact closure and opening. Range adjustment is attained by turning a knob which acts through a cam on the pivotal mounts to vary the angle between the bimetal plates thereby to require more or less bimetal bending for contact actuation.
摘要:
A toggle switch having a molded insulating frame mounting a snap-in bushing secured thereto for snap-in mounting of the switch in a hole in a mounting pane. This bushing pivotally retains the toggle lever for operating the switch contacts within the base. This frame includes a pair of depending legs between which the insulating switch base is snap-in mounted and retained. This frame has integrally molded therewith a pair of oppositely disposed resilient back-up elements for pressing against the back of the panel, these elements having at their ends ramped riser bars for accommodating a range of different panel thicknesses while retaining the switch against significant movement on the panel during toggle lever operation.
摘要:
A protection apparatus is for a direct current electrical generating apparatus. The protection apparatus includes a first terminal; a second terminal; a third terminal; a fourth terminal; at least one current sensor structured to sense current flowing between the first and second terminals or between the third and fourth terminals; a voltage sensor structured to sense a voltage between the first terminal and the third terminal; at least one switch structured to interrupt the current flowing between the first and second terminals or between the third and fourth terminals; and a processor cooperating with the at least one current sensor, the voltage sensor and the at least one switch, and being structured to provide feed forward fault protection for the direct current electrical generating apparatus.
摘要:
A direct current arc fault circuit interrupter includes separable contacts and a trip circuit to trip open the contacts. The trip circuit includes a number of alternating current sensors structured to sense a current flowing through the separable contacts, a number of filter circuits cooperating with the AC current sensors to output a number of AC signals, a number of peak detectors cooperating with the filter circuits to output a number of peak current signals, and a processor cooperating with at least the peak detectors. The processor inputs the number of peak current signals as a plurality of peak current signals or inputs the number of peak current signals and determines the plurality of peak current signals. The processor also determines if the peak current signals exceed corresponding predetermined thresholds for a predetermined time, and responsively causes the contacts to trip open.
摘要:
Electrical equipment (14) is safeguarded from damage due to parallel arc faults by a circuit that provides several levels of protection. A semiconductor switch (18) and a current sensor (24) are placed in series with the electrical equipment (14). When the current to the equipment exceeds a first threshold for a predefined period of time, the semiconductor switch (18) is rendered non-conductive until the circuit is specifically reset. When the current to the equipment exceeds a greater second threshold, a pulsed signal alternately places the semiconductor switch (18) in conductive and non-conductive states so that the average current applied to the equipment (14) is within an acceptable level. The pulses are measured to determine whether a parallel arc fault has occurred. When the measured pulses (74) are within a predetermined range, a parallel arc fault is declared and the semiconductor switch (18) is rendered non-conductive. Should the current exceed an even greater third threshold, the semiconductor switch (18) is immediately rendered non-conductive until the circuit is manually reset.
摘要:
A bypass contactor usable in a solid state motor starter for shunting current around a fully-conducting solid state switching device comprising an electromagnetic contactor housed in a molded insulating enclosure having a plurality of bridging contacts movable into and out of engagement with a pair of stationary contacts to provide plural parallel current paths within the contactor, the stationary contacts having rigid terminal portions projecting externally of the insulating enclosure connectable to the heat sinks of the solid state motor starter in a preferred manner to suspend the contactor above the panel, permitting other components to be mounted below the bypass contacts. Alternate embodiments have the contactor mounted to the same support as the starter power pole component assembly and electrically connected thereto by rigid preformed connectors or flexible braided straps. Also contemplated is increasing the rated current handling capacity by mounting a pair of the bypass contactors to the heat sinks in parallel to double the parallel current paths.