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公开(公告)号：US4250532A
公开(公告)日：1981-02-10
申请号：US11388
申请日：1979-02-12
申请人： Lee A. Davis
发明人： Lee A. Davis
摘要： An electronic overcurrent detection and tripping circuit for circuit breakers is disclosed. The circuit includes an instantaneous trip circuit, a short time delay trip circuit, a long time delay trip circuit and a ground trip circuit. Each of the circuits is provided with adjustable ranges which can be set by suitable tap blocks or the like. A novel power supply is provided for the circuit which incorporates a unique series-connected zener diode and sensing resistor. The power supply circuit also provides sufficient power for tripping a magnetic latch of the circuit breaker whose current is being monitored. Each of the circuit functions can be disabled for purposes of tests by simply placing the function tap block pin in an appropriate test position.
摘要翻译： 公开了一种用于断路器的电子过电流检测和跳闸电路。 该电路包括瞬时跳闸电路，短时间延迟跳闸电路，长时间延迟跳闸电路和接地跳闸电路。 每个电路都具有可由适当的抽头块等设置的可调范围。 为电路提供了一种新颖的电源，该电路采用独特的串联连接的齐纳二极管和感测电阻。 电源电路还提供足够的电力来跳闸正在监视其电流的断路器的磁性闩锁。 通过简单地将功能分接开关销置于适当的测试位置，可以禁止每个电路功能用于测试。
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公开(公告)号：US4246623A
公开(公告)日：1981-01-20
申请号：US940801
申请日：1978-09-08
申请人： Shan C. Sun
发明人： Shan C. Sun
CPC分类号： H02H3/0935 , H02H1/066
摘要： An electrical device for protecting an alternating current network in which a static inverse time-overcurrent relay obtains network current information and relay circuit operating power from a current transformer having two secondary windings. Low transformer burden and accurate network information signals that are linearly responsive to a wide range of network current magnitudes are achieved through the use of a switching circuit that prevents the simultaneous operation of both secondary windings. The relay circuit employs an RC network with a short, precision time constant for curve shaping and employs digital counting techniques to provide time delay multiplication, precision time scale selection and a variable delay time variable in accordance with the magnitude of system current.
摘要翻译： 一种用于保护交流网络的电气设备，其中静态反时限过电流继电器从具有两个次级绕组的电流互感器获得网络电流信息并中继电路工作功率。 通过使用防止两个次级绕组的同时操作的开关电路来实现对宽范围的网络电流幅度线性响应的低变压器负载和精确的网络信息信号。 继电器电路使用RC网络，具有短的精确时间常数用于曲线整形，并采用数字计数技术，根据系统电流的大小提供时间延迟乘法，精确时标选择和可变延迟时间变量。
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公开(公告)号：US4241372A
公开(公告)日：1980-12-23
申请号：US16411
申请日：1979-03-01
申请人： Kay G. Sears
发明人： Kay G. Sears
摘要： A protective system interposed between a d-c power supply and an external load to isolate the supply from the load should the current drawn therefrom exceed a predetermined threshold value, the system distinguishing between a transitory overload and a continuous overload condition. The system includes a current-sensing resistor connected in series with the supply and the load and a comparator responsive to the voltage drop developed across the resistor to produce an output signal which activates a relay to cut off the delivery of current to the load only when the current exceeds the threshold value. Also included is a sampling circuit which upon activation of the relay functions after a brief sampling interval to automatically de-activate the relay and thereby reconnect the supply to the load, causing the comparator to again determine whether the existing current drain is still excessive, in which event the relay is again activated and the sampling cycle repeated. A timing-out circuit operates in conjunction with the sampling circuit to permit the sampling cycle to continue repetitively as long as an overcurrent condition is sensed. However, at the conclusion of a timing-out period which is a multiple of the sampling interval, if an overcurrent condition still exists, the timing-out circuit acts to reactivate the relay and cut off the delivery of current to the load and to hold the relay in its activated state.
摘要翻译： 其中介于d-c电源和外部负载之间以将电源与负载隔离的保护系统应当从其中抽出的电流超过预定阈值，该系统区分暂时过载和连续过载状况。 该系统包括与电源和负载串联的电流检测电阻器和响应于电阻器两端产生的电压降的比较器，产生输出信号，该输出信号激活继电器以仅在当 电流超过阈值。 还包括采样电路，其在短暂采样间隔之后激活继电器功能以自动停用继电器，从而将电源重新连接到负载，使得比较器再次确定现有的电流消耗是否仍然过大， 再次激活继电器并重复采样周期。 定时电路与采样电路一起工作，只要检测到过电流条件，允许采样周期重复继续。 然而，在采样间隔的倍数的结束时，如果过电流状况仍然存在，则超时电路用于重新激活继电器并切断对负载的电流传递并保持 继电器处于其激活状态。
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公开(公告)号：US4208689A
公开(公告)日：1980-06-17
申请号：US886962
申请日：1978-03-15
摘要： A circuit breaker having an electronic fault sensing and trip initiating unit which provides increased versatility and ability to coordinate the circuit breaker with other interrupting and protective devices in a wide variety of electrical distribution systems. Electronic circuits and components are provided to vary the ampere rating of the breaker, to adjust current carrying capacity, to provide a long time delay trip, a short time delay trip and an instantaneous trip depending on the amplitude of high fault currents, to provide a ground fault trip, to shorten or lengthen the trip time for short time delay faults and for ground faults, and to provide shunt trip capability. The tripping mechanism is magnetic and mechanical, and includes a plunger movable between a trip and non-trip position controlled by an electronic switch in the electronic circuitry, and a toggle mechanism which is unlatched by the plunger when it moves to the trip position. A bimetal trip mechanism is provided as back-up protection if the ambient temperature not sensed by the electronic circuitry exceeds a pre-determined level.
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公开(公告)号：US4152744A
公开(公告)日：1979-05-01
申请号：US807585
申请日：1977-06-17
申请人： Peter Pang
发明人： Peter Pang
CPC分类号： H02H1/0007 , H02H3/093
摘要： The primary winding of a saturable transformer, coupled to an a.c. circuit, drives the core of the transformer into saturation during at least a portion of the cycle of an a.c. current flowing through the circuit. A plurality of rise-time indicator pulses, having a duration inversely proportional to the rate of rise of the a.c. current being monitored, is induced in the secondary winding of the saturable transformer. The rise-time indicator pulses appearing in the secondary winding of the saturable transformer are applied to a pick-up circuit which generates a plurality of rectangular pulses whenever the a.c. current exceeds the normal rated value of the circuit. The pulses generated by the pick-up circuit each have a duty cycle inversely proportional to the rate of rise of the a.c. current being monitored. An inverter circuit, responsive to the pulses generated by the pick-up circuit, generates a second series of rectangular pulses having a duty cycle proportional to the rate of rise of the a.c. current being monitored. The second series of pulses are applied to a tripping circuit which monitors the duty cycles of these pulses and interrupts a.c. current flow in said circuit after a time delay which is inversely proportional to the magnitude of the a.c. current being monitored.
摘要翻译： 饱和变压器的初级绕组，耦合到一个直流 电路在变压器的核心在直流电的循环的至少一部分期间驱动饱和。 流过电路的电流。 多个上升时间指示符脉冲，其持续时间与a.c.的上升速率成反比。 被监测的电流在可饱和变压器的次级绕组中感应出来。 出现在可饱和变压器的次级绕组中的上升时间指示器脉冲被施加到拾取电路，每当交流电流产生多个矩形脉冲。 电流超过电路的正常额定值。 由拾取电路产生的脉冲各自具有与a.c.的上升率成反比的占空比。 正在监视。 响应于拾取电路产生的脉冲的逆变器电路产生具有与交流电的上升速率成比例的占空比的第二系列矩形脉冲。 正在监视。 第二系列脉冲被施加到跳闸电路，该跳闸电路监视这些脉冲的占空比并中断a.c. 在与a.c.的大小成反比的时间延迟之后的所述电路中的电流。 正在监视。
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106.发明授权Motor protector providing phase failure and overload cutoff for three-phase variable voltage variable frequency motor 失效电机保护器为三相可变电压变频电机提供相位故障和过载切断
公开(公告)号：US4103317A
公开(公告)日：1978-07-25
申请号：US693421
申请日：1976-06-07
申请人： John B. Krick
发明人： John B. Krick
摘要： A circuit for a polyphase motor which operates in response to undesirable operating conditions so as to prevent damage to the electric motor. The protection circuit converts current to voltage over a range of operating currents. The current sensitive voltage in response to an undesired current condition triggers the operation of a gating circuit to apply potential to an output switch which in turn controls the current supply and stops the motor. The gating circuit is also triggered by a detector circuit sensing a deficiency in motor current to thereby actuate the output switch and interrupt the motor operation and thus protect the motor. A timing circuit provides an inverse time function in conjunction with the voltage applied to the gating circuit. The timing circuit is adjustable to provide adjustability in the elapsed time for providing a triggering voltage to the gating circuit.
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公开(公告)号：US4054934A
公开(公告)日：1977-10-18
申请号：US662248
申请日：1976-02-27
申请人： Richard E. Riebs
发明人： Richard E. Riebs
CPC分类号： H02H3/093 , H02H1/0069
摘要： A solid state inverse overcurrent relay having a long slender wire connected to respond to a current which is proportional to the line current in a power system. An infrared detector or phototransistor is positioned to sense a predetermined color of radiation from the wire and is connected to fire a silicon controlled rectifier which is connected in series with a trip coil for a circuit breaker. The trip coil and silicon controlled rectifier are connected to an independent DC power source. The long slender wire on energization responds to the current which is proportional line current with the same time current characteristic as a fuse. In an alternate embodiment of the invention the relay is connected to the power system through a bridge rectifier which provides the DC current for operating both the heat responsive wire as well as the infrared detector.
摘要翻译： 固态反向过电流继电器，其具有连接的长细线，以响应与电力系统中的线路电流成比例的电流。 定位红外检测器或光电晶体管以感测来自导线的预定颜色的辐射，并且连接以激发与用于断路器的跳闸线圈串联连接的可控硅整流器。 跳闸线圈和可控硅整流器连接到独立的直流电源。 通电时长的细长电线将以与保险丝相同的时间电流特性作为比例线路电流的电流进行响应。 在本发明的替代实施例中，继电器通过桥式整流器连接到电力系统，桥式整流器提供用于操作热响应导线以及红外检测器的DC电流。
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公开(公告)号：US4048663A
公开(公告)日：1977-09-13
申请号：US654423
申请日：1976-02-02
申请人： Winfred R. Lemke
发明人： Winfred R. Lemke
摘要： A self-powered solid state overload relay having current transformers energized by current to a motor to be protected. The transformer has secondary windings connected through diodes to charge a capacitor in a circuit which senses the magnitude of motor current and capacitors in a trip-reset circuit which causes the circuit to be interrupted when the motor current exceeds a pre-programmed value. The diodes in capacitor charging circuits are poled so that the capacitor in the sensing circuit and the capacitor trip-reset circuit are charged by opposite polarity rectified half wave current pulses. The cores of the transformers are sized and impedances are included in the charging circuits to cause the capacitors in the trip-reset circuit to be fully charged before the capacitor in the sensing circuit is charged to a level which would cause the relay to operate to interrupt the motor circuit and the cores of the transformers to saturate in one direction on their associated hysteresis loops when the capacitors in the trip-reset circuit are being charged and in the opposite direction after the capacitor in the sensing circuit is charged.
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公开(公告)号：US4041540A
公开(公告)日：1977-08-09
申请号：US654425
申请日：1976-02-02
CPC分类号： H02H3/093
摘要： A self-powered solid state overload relay circuit having current transformers energized by conductors supplying current to a multiphase alternating current motor. The transformers have secondary windings connected to charge a capacitor with a voltage indicative of the magnitude of the maximum current in the motor windings. The circuit includes presetable impedance circuits which permit the circuit to be easily programmed to respond to a range of abnormal motor currents in the winding in motors of varying size and service factor ratings, components which are arranged to duplicate the operation of melting alloy and bimetal type overload relays in an automatic or in a trip-free manual reset mode, a light emitting device which visually indicates when the relay is in a tripped state, and components which cause the relay to be insensitive to ambient temperature variations.
摘要翻译： 一种自供电的固态过载继电器电路，其具有通过向多相交流电动机提供电流的导体供电的电流互感器。 变压器具有连接到电容器的次级绕组，其中电压表示电动机绕组中最大电流的大小。 该电路包括可预设的阻抗电路，其允许电路容易地被编程以响应不同尺寸和使用系数额定值的电动机中的绕组中的异常电动机电流的范围，这些组件被布置为复制熔融合金和双金属型的操作 自动或无跳闸手动复位模式的过载继电器，可视地指示继电器何时处于跳闸状态的发光装置以及使继电器对环境温度变化不敏感的部件。
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公开(公告)号：US4027203A
公开(公告)日：1977-05-31
申请号：US555947
申请日：1975-03-06
摘要： A protective device includes a circuit breaker with an operating means connected to a fault current sensing control circuit. A small line current and/or a small fault current sensing current transformer means is conductively connected through individual rectifiers and series sensing resistors as a current source to charge a common power supply capacitor. A voltage limiting means across the capacitor maintains the current source. A high impedance signal processing amplifier includes a sensing transistor connected to the sensing resistor which establishes a minimum trip level and driving coupling transistors connected to the capacitor and including voltage sensitive means to positively inhibit full amplifier turn-on before the power supply capacitor is charged to an operating voltage level. In a fault condition, the amplifier rapidly charges a hold-on capacitor which slowly discharges to activate a timing control transistor of a time delay circuit, the output of which triggers a rapid, stabilized switch to operate the circuit breaker. The timing circuit may be driven from the power supply capacitor or a separate timing source capacitor which rapidly charges to the peak value of the sensing resistor and slowly discharges to establish a relatively constant and high average current such that timing is not sensitive to current transformer saturation. Where both line and ground fault sensors are connected to the common amplifier, they share the same timing means and have the same delay curves with a significant reduction in circuit cost and complexity. A clamping network may be connected to the sensing resistor to also minimize transformer core saturation and establish a maximum timing current and allow heavy fault currents of short duration.
摘要翻译： 保护装置包括具有连接到故障电流感测控制电路的操作装置的断路器。 小型线路电流和/或小故障电流检测电流互感器装置通过单独的整流器和串联感测电阻器作为电流源导电连接，以对公共电源电容器充电。 电容器两端的电压限制装置保持电流源。 高阻抗信号处理放大器包括连接到感测电阻器的感测晶体管，其建立最小跳闸电平并驱动连接到电容器的耦合晶体管，并且包括电压敏感装置，以在电源电容器被充电之前肯定地禁止全放大器接通 工作电压电平。 在故障状态下，放大器对缓慢放电的保持电容器进行快速充电，以激活时间延迟电路的定时控制晶体管，其输出触发快速稳定的开关来操作断路器。 定时电路可以从电源电容器或单独的定时源电容器驱动，其将快速充电到感测电阻器的峰值并缓慢放电以建立相对恒定和高平均电流，使得定时对电流互感器饱和不敏感 。 当线路和接地故障传感器连接到公共放大器时，它们共享相同的定时装置并具有相同的延迟曲线，显着降低电路成本和复杂性。 钳位网络可以连接到感测电阻器，以使变压器磁芯饱和度最小化并建立最大定时电流，并允许短时间内的重故障电流。
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