KR880001149B1 - Over current relay - Google Patents

Over current relay Download PDF

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KR880001149B1
KR880001149B1 KR1019850002996A KR850002996A KR880001149B1 KR 880001149 B1 KR880001149 B1 KR 880001149B1 KR 1019850002996 A KR1019850002996 A KR 1019850002996A KR 850002996 A KR850002996 A KR 850002996A KR 880001149 B1 KR880001149 B1 KR 880001149B1
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South Korea
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integrated circuit
diode
resistor
relay
input
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KR1019850002996A
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Korean (ko)
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KR860009450A (en
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김인석
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김인석
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Priority to KR1019850002996A priority Critical patent/KR880001149B1/en
Priority to EP86900857A priority patent/EP0221185B1/en
Priority to PCT/KR1986/000003 priority patent/WO1986006562A1/en
Publication of KR860009450A publication Critical patent/KR860009450A/en
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Publication of KR880001149B1 publication Critical patent/KR880001149B1/en
Priority to US07/256,138 priority patent/US4879626A/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00—Mechanisms for operating contacts
    • H01H3/02—Operating parts, i.e. for operating driving mechanism by a mechanical force external to the switch
    • H01H3/08—Turn knobs
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current

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  • Emergency Protection Circuit Devices (AREA)
  • Relay Circuits (AREA)

Abstract

This electronic overcurrent relay employs the Schmitt trigger integrated circuit. The commonly used relay can be used regardless of the magnitude of load with prompt dicrimination of overload state. If the source voltage is applied to the input of the relay, the source is rectified in bridge diode (D1) through the resistance (R1) and AC condenser (C1). The rectified voltage is filtered by the condensers C2, C3 and the resistance R2. The filtered voltage is supplied to the schmitt trigger circuit through the zener diode (D3).

Description

과전류 릴레이Overcurrent relay

제1도는 본 발명의 회로도.1 is a circuit diagram of the present invention.

* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings

CT1,CT2: 변류기 R1-R10: 저항CT 1 , CT 2 : Current transformer R 1 -R 10 : Resistance

R11은 써미스터 저항 C1-C6: 콘덴서R 11 is thermistor resistor C 1 -C 6 : capacitor

D1: 브리지 다이오드 D2: 발광다이오드D 1 : bridge diode D 2 : light emitting diode

D3: 제너다이오드 D4-D12: 다이오드D 3 : Zener Diodes D 4 -D 12 : Diodes

IC-IC6: 슈미트 트리거 집적회로 TR1, TR2, TR3: 트랜지스터IC-IC 6 : Schmitt trigger integrated circuit TR 1 , TR 2 , TR 3 : Transistor

VR1, VR2, VR3: 가변저항 K : 릴레이VR 1 , VR 2 , VR 3 : Variable resistor K: Relay

본 발명은 슈미트 트리거 집적회로를 응용한 전자식 과전류 릴레이에 관한 것이다.The present invention relates to an electronic overcurrent relay using a Schmitt trigger integrated circuit.

최근들어 전자산업의 발달과 함께 수많은 전자방식의 과전류 보호용 릴레이가 개발된바 있으나 그 구조가 매우 복잡하고 과부하 상태를 제대로 식별할 수가 없었으며, 양산이 불가능하였을 뿐만 아니라 가격이 고가인 단점이 있었다.Recently, with the development of the electronics industry, a number of electronic overcurrent protection relays have been developed, but the structure is very complicated, the overload condition cannot be properly identified, mass production was impossible, and the price was expensive.

본 발명은 상기와 같은 종래의 과전류 릴레이가 갖는 제결함을 감안하여 부하의대소에 관계없이 사용할 수 있는 범용성 릴레이로써 과부하 상태의 즉시 식별이 가능하고, 부하의 촌동성 기동에 의한 과부하 신호의 축적 예방이 가능하며,오동작이 전혀 없고, 릴레이 입력전압이 사용범위가 넓으며, 구조가 간단하고, 순시요소가 내장된 정한시성 과전류 릴레이로써 소형이며 경량인 저가의 과전류 릴레이를 제공할 목적으로 안출할 것으로, 본 릴레이는 과전류 정정의 정밀도가 0.1A 이하의 미세전류까지 임의로 정정 가능하고 동작시간도 수 싸이클부터 수십초까지 조정이 가능하여 발전소, 변전소의 기존유도형 과전류 계전기의 대체용으로써 사용가능하며, 가격이 염가이고 전력손실이 거의 없기 때문에 써멀릴레이(연동형과 전류릴레이)의 대체용으로도 사용가능함은 물론 엄청난 절전효과를 가져오므로써 산업발전에 지대한 이익을 줄수 있는 발명인 것이다.The present invention is a general-purpose relay that can be used regardless of the load in consideration of the deficiencies of the conventional overcurrent relay as described above, and enables immediate identification of the overload condition, and prevents the accumulation of the overload signal due to the unstable start of the load. It is possible to have no malfunction, no wide range of relay input voltage, simple structure, and instantaneous element built-in time delay overcurrent relay. This relay can be arbitrarily corrected to fine current of 0.1A or less, and the operation time can be adjusted from several cycles to several tens of seconds. The low cost and almost no power loss make it an alternative to thermal relays (interlocked and current relays). Of course, it is also possible to use inventions that give great benefit to the industry as a fetches a huge power savings.

본 발명을 첨부회로 도면에 의거 상세히 설명하면 다음과 같다.The present invention will be described in detail with reference to the accompanying circuit drawings.

도면중 R.S.T는 삼상전원단자이고, CT1,CT2는 관통형 변류기이며, MS는 마그네트스위치이고, LOAD는 교류부하를 나타낸 것으로, 릴레이 입력 전원은 단상교류로써 전원단자(1)(2)에 전원이 공급되면 저항(R1)과 교류 콘덴서(C1)를 통하여 브리지다이오드(D1)에서 정류된 후 평활 회로인 콘덴서(C2),(C3) 및 저항(R2)에 의해 휠터되고, 다시 제너다이오드(D3)에 의해 정전압을 유지하면서 슈미트트리거 집적회로의 전원으로 공급되게 된다.In the figure, RST is a three-phase power terminal, CT 1 and CT 2 are through current transformers, MS is a magnet switch, LOAD represents an AC load, and the relay input power is a single-phase AC to the power terminals (1) and (2). When power is supplied, it is rectified at the bridge diode (D 1 ) through a resistor (R 1 ) and an alternating capacitor (C 1 ) and then filtered through the smoothing circuits of capacitors (C 2 ), (C 3 ) and resistor (R 2 ). Then, the zener diode D 3 is supplied to the Schmitt trigger integrated circuit while maintaining the constant voltage.

한편, 변류기(CT1),(CT2)에 의해서 감지된 과전류 세력은 상호 간섭방지용 다이오드(D4)(D5)에 의해 정류되어 전류 정정용 가변저항(VR1)의 양단에 전압으로 나타나게 되고, 그 크기는 부하전류에 비례해서 나타나게 된다. 여기서 가변저항(VR1)과 병렬로 연결된 저항R11은 온도보상용 써미스터 저항이며, VR2는 순시요소(단락전류) 설정용 가변저항이다.Meanwhile, the overcurrent forces sensed by the current transformers CT 1 and CT 2 are rectified by the mutual interference prevention diodes D 4 and D 5 to appear as voltages across the current correction variable resistor VR 1 . The magnitude of the load will appear in proportion to the load current. Here, resistor R 11 connected in parallel with the variable resistor VR 1 is a temperature compensation thermistor resistor, and VR 2 is a variable resistor for setting the instantaneous element (short circuit current).

가변저항(VR1)의 양단에 걸린 신호전압의 크기가 트랜지스터(TR1)의 베이스전압 이상이 되면 트랜지스(TR1)가 도통되어 그의 콜렉터에 연결된 집적회로(IC1)(IC4)의 입력측에는 '로우" 상태의폭이 좁은 구형파 신호가 형성되고 각 집접회로(IC1)(IC4)의 출력측에는 위상이 반전된 "하이" 상태의 신호가 나타나 다이오드(D6)와 저항(R4)를 통하여 발광다이오드(D2)를 점등시켜서 과부하개시 상태를 외부로 표시해주고 그 세력의일부가 저항(R5)과 콘덴서(C6)의 시정수에 따라 집접회로(IC2)의 입력에 "하이" 상태의 신호를 공급하게 되면, 집적회로(IC2)의 출력은 "로우"가 되고, 집적회로(IC3)의 출력은"하이"가 되어 저항(R7)을 통해 직류 릴레이(K)와 연결된 트랜지스터(TR2)의 베이스에 인가되어 트랜지스터(TR2)를 "온"시키게 된다.When the magnitude of the signal voltage across the variable resistor VR 1 is greater than or equal to the base voltage of the transistor TR 1 , the transistor TR 1 is turned on to connect the integrated circuit IC 1 (IC 4 ) connected to the collector thereof. On the input side, a narrow wave signal with a narrow 'low' state is formed, and on the output side of each of the integrated circuits IC 1 and IC 4 , a signal having a high phase with an inverted phase is displayed, and a diode D 6 and a resistor R 4 ) Light-emitting diode (D 2 ) is turned on to indicate the overload start state to the outside, and part of the forces is input to the integrated circuit (IC 2 ) according to the time constant of the resistor (R 5 ) and condenser (C 6 ). When the signal of the "high" state is supplied to the integrated circuit IC 2 , the output of the integrated circuit IC 2 becomes low, and the output of the integrated circuit IC 3 becomes high, and the DC relay is connected through the resistor R 7 . It is applied to the base of the transistor TR 2 connected with K to turn on the transistor TR 2 .

이와같이 트랜지스터(TR2)가 도통되면 직류 릴레이(K)가 동작하여 릴레이의 a,b 보조접점(3)(4)(5)을 개폐시키게 되는 것으로 그 접점을 수배전반 씨켄스에 응용하면 되는 것이다.As described above, when the transistor TR 2 is turned on, the DC relay K operates to open and close the a, b auxiliary contacts 3, 4, and 5 of the relay, and the contact point may be applied to the switchboard switch.

일단, 직류 릴레이가 동작하게 되면 휘드백다이오드(D7)와 저항(R6)을 통해 직접회로(IC3)의 입력으로 휘드백되어 지속적으로 직류 릴레이(K)의 "온"상태를 계속 유지해주고, 이때 발광다이오드(D2)에도 다이오드(D10)를 통해서 전류가 계속 인가되어 과부하 동작상태를 계속 표시해 주게 된다.Once the DC relay is activated, it is feedbacked to the input of the integrated circuit (IC 3 ) through the feedback diode (D 7 ) and the resistor (R 6 ) to continuously maintain the "ON" state of the DC relay (K). At this time, the current is continuously applied to the light emitting diode D 2 through the diode D 10 to continuously display the overload operation state.

여기서 회로를 리세트 시키고져 할 경우에는 저항(R10)에 연결설치된 리세트 버튼(RS)을 눌러 콘덴서(C6)의 충전을 방전시키든가 브리지다이오드(D1)에 연결된 릴레이 입력전원단자(1)(2)의 입력전원을 순간적으로 '오프"시키면 리세트로 되는 것이다.In this case, to reset the circuit, press the reset button RS connected to the resistor R 10 to discharge the charge of the capacitor C 6 or the relay input power terminal connected to the bridge diode D 1 . If the input power of 1) (2) is momentarily 'off', it will be reset.

이상에서 설명한 것은 정상운전시에 나타난 동작순서이고, 어떤 부하든지 부하 기동시나 선로 충전시에는 수배의 기동전류나 돌입전류가 흐르게 된다. 그러면 이상의 회로만으론 기동시는 계속 과부하 동작이 되므로 기동시나 과부하시에 그 동작시간을 지연시킬 필요가 있게 된다.The above is the operation sequence shown in normal operation, and any load has several times of starting current or inrush current when the load is started or the line is charged. Then, with the above circuit, since the overload operation continues during startup, it is necessary to delay the operation time during startup or overload.

이 지연회로를 설명하면, 과부하동작 집적회로(IC1)의 입력에 나타난 "로우" 상태의 과전류 신호가 동작지연 집적회로(IC4)의 입력에도 동시에 가해져 그의 출력측에는 "하이" 상태의 신호가 출력되어 다이오드(D12)를 거쳐 직접회로(IC5)에 입력되어 그의 출력측에는 "로우" 상태의 신호가 출력되게 된다.In the description of this delay circuit, an overcurrent signal in the "low" state shown at the input of the overload operation integrated circuit IC 1 is simultaneously applied to the input of the operation delay integrated circuit IC 4 so that a signal in the "high" state is applied at its output side. The signal is output to the integrated circuit IC 5 via the diode D 12 , and a signal of a low state is output to the output side thereof.

여기서 정상시에는 집접회로(IC6)의 입력은 콘덴서(C5)에 의해 "하이" 상태로 되고, 그의 출력은 "로우" 상태가 되어 있는 상태에서, 직접회로(IC2)의 입력측에 과부하 신호인 "하이" 상태의 신호가 들어와도 다이오드(D8)를 통해 방전해 버리므로 과부하 동작이 보류되고 다만 발광다이오드(D2)만 점등된다. 그런데 위에서 설명한 지연 회로에서 집적회로(IC5)의 출력이 "로우"가 되면 지연시간 설정용 가변저항(VR3)을 통해 콘덴서(C5)가 서서히 방전되어 "로우" 상태로 되면 집적회로(IC6)의 출력이 "하이"가 되어 집적회로(IC2)입력의 방전이 중지되므로 즉시 과부하 동작이 되게된다. 여기서 다이오드(D9)는 과부하 동작상태에서 집적회로(IC3)의 출력에 나타난 "하이" 상태를, 동작지연 집적회로(IC5)의 입력측에 "하이" 신호를 휘드백 시켜주는 역활을 하며, 집적회로(IC4)의 출력측에 연결된 다이오드(D12)는 이 "하이" 상태의 신호를 "로우"상태인 집적회로(IC4)의 출력과 격리시키기 위한 브로킹 다이오드이다.In this case, the input of the integrated circuit IC 6 is "high" by the capacitor C 5 , and the output thereof is "low", and the input side of the integrated circuit IC 2 is overloaded. Even when a signal of the "high" state, which is a signal, is discharged through the diode D 8 , the overload operation is suspended and only the light emitting diode D 2 is turned on. However, when the output of the integrated circuit IC 5 becomes "low" in the above-described delay circuit, the capacitor C 5 is gradually discharged to the "low" state through the variable resistor VR 3 for setting the delay time. The output of IC 6 ) becomes "high" and the discharge of the integrated circuit (IC 2 ) input is stopped so that the overload operation occurs immediately. Here, the diode D 9 serves to "back" the "high" state shown at the output of the integrated circuit IC 3 and overload the "high" signal to the input side of the operation delay integrated circuit IC 5 in an overload operation state. is bromo King diode to the output and isolation of an integrated circuit (IC 4) a diode (D 12) is a "high""low" state of the integrated circuit (IC 4) connected to the output side of the signal.

한편, 가변저항(VR4)과 병렬로 써미스터저항(R6)을 설치하여 외기온도변화에 따른 오차를 보상하고 순시요소 선정용 가변저항(R6)을 설치하여 그 중간 텝에서 설정한 과전류 신호전압을, 집적회로(IC3)의 입력측에 저항(R6)를 통해 설치한 트랜지스터(TR3)의 베이스에 인가하여 트랜지스터(TR3)를 스위칭시키므로서 선로 단락사고시에 순간적으로 트랜지스터(TR3)를 "온" 시키면 집적회로(IC3)의 입력이 "로우"가 되고 그의 출력이 "하이"가 되므로 트랜지스터(TR1)가 도통으로 직류 릴레이(K)가 동작하여 선로 단락사고시의 과전류 보호가 이루워지게 되는 것이다.On the other hand, the thermistor resistor (R 6 ) is installed in parallel with the variable resistor (VR 4 ) to compensate for the error caused by the change in the outside temperature, and the overcurrent signal set in the middle tap by installing the variable resistor (R 6 ) for instantaneous element selection. the voltage, the integrated circuit is applied to the base of a transistor (TR 3) installed through the resistor (R 6) on the input side of the (IC 3) to the transistor (TR 3) for because standing momentarily transistor (TR 3 in the line short-circuiting accident switching ), The input of the integrated circuit (IC 3 ) becomes "low" and its output becomes "high" so that the transistor (TR 1 ) conducts the DC relay (K) by conduction and protects the overcurrent during a line short circuit accident. Will be achieved.

이와같이 본 발명은 동작원리가 간단하고, 회로가 단순하면서 동작이 정밀, 정확하고 가격이 저렴한 과전류 릴레이를 제공함으로써 송배전 선로의 계통사고를 방지하고, 산업용 주요기기를 보호하고 돌발사고를 미연에 방지하여 생산성을 향상시키며, 유지보수비를 절감하고, 전력 손실을 방지할 수 있는 그 실사용 가치가 일층 고양된 획기적인 발명인 것이다.As described above, the present invention provides an overcurrent relay with simple operation principle, simple circuit, precise operation, low cost, and prevents system accidents on transmission and distribution lines, protects major industrial equipment, and prevents accidents. It is a revolutionary invention that has enhanced its practical value to improve productivity, reduce maintenance costs, and prevent power loss.

Claims (1)

변류기(T1)(T2)에서 감지된 전류 세력이 브로킹다이오드(D4)(D5)를 통해 가변저항(VR1)에 걸리고 그 중간탭을 통하여 트랜지스터(TR1)의 베이스에 인가되는 한편, 콘덴서(C1)(C2)(C3)및 저항(R1)(R2)과 제너다이오드(D3)로 구성된 정전압 회로에 릴레이 입력전원이 입력되는 과전류 릴레이 회로에 있어서, 신호입력측에 가변저항(VR2)과 병렬로 온도보상용 써미스터저항(R11)과 순시요소 설정용 가변저항(VR2)을 설치하고, 상기 가변저항(VR2) 중간탭을, 저항(R9)을 통해 집적회로(IC3)의 입력측에 연결된 트랜지스터(TR3)의 베이스에 연결하고, 집적회로(IC1)(IC4)와 트랜지스터(TR1)를 저항(R3)를 통해 상기 정전압 회로에 연결하며, 상기 과부하동작 집적회로(IC1)를 저항(R5)을 거쳐 집적회로(IC2)(IC3)에 연결하고 그의 출력을 저항(R7)을 통하여 콜렉터에 직류 릴레이(K)가 연결된 트랜지스터(TR2)의 베이스에 연결하고, 집적회로(IC3)의 출력을 다이오드(10)를 거쳐 저항(R4)을 통하여 발광다이오드(D2)에 연결함과 동시에 다이오드(D7) 콘덴서(C6)와 리세트 버튼(RS)이 연결된 집적회로(IC2)의 입력에 연결하고, 다이오드(D9)를 통하여 집적회로(IC5)에 연결하며, 동작지연 집적회(IC4)로의 출력을 다이오드(D12)를 통하여 콘덴서(C4)와 집적회로(IC5)에 연결하고 그의 출력을 가변저항(VR3)을 거쳐 집적회로(IC6)의 입력에 연결된 콘덴서와 연결함과 동시에 다이오드(D11)를 통하여 집적회로(IC6)에 연결구성하여서 된 전자식 과전류 릴레이.Current forces sensed by the current transformer (T 1 ) (T 2 ) are applied to the variable resistor (VR 1 ) through the breaking diode (D 4 ) (D 5 ) and applied to the base of the transistor (TR 1 ) through its intermediate tap. In the overcurrent relay circuit in which a relay input power is input to a constant voltage circuit composed of a capacitor (C 1 ) (C 2 ) (C 3 ) and a resistor (R 1 ) (R 2 ) and a zener diode (D 3 ), a variable resistor (VR 2) and parallel to the installation temperature compensation for the thermistor resistance (R 11) and the instantaneous element variable resistor (VR 2) for setting, and the variable resistor (VR 2) intermediate tap to the signal input side, the resistance (R 9 ) is connected to the base of the transistor TR 3 connected to the input side of the integrated circuit IC 3 , and the integrated circuit IC 1 IC 4 and the transistor TR 1 are connected through the resistor R 3 . and connected to a constant-voltage circuit, the overload operation integrated circuit (IC 1) a resistor (R 5) via an integrated circuit (IC 2) connected to (IC 3), and through its output resistance (R 7) On a direct current relay (K) is connected to the base of the associated transistor (TR 2) to a collector, and an integrated circuit light emitting diode (D 2), the output of the (IC 3) via a diode 10 through a resistor (R 4) Connect to the input of the integrated circuit (IC 2 ) connected to the diode (D 7 ) capacitor (C 6 ) and the reset button (RS) at the same time, and to the integrated circuit (IC 5 ) through the diode (D 9 ) and, via a diode (D 12) output to the operation delay integrated circuit (IC 4) connected to the capacitor (C 4) as an integrated circuit (IC 5) and via a variable resistor (VR 3) to its output integrated circuit (IC 6 ) An electronic overcurrent relay that is connected to an integrated circuit (IC 6 ) through a diode (D 11 ) and connected to a capacitor connected to the input of the circuit.
KR1019850002996A 1984-09-01 1985-05-02 Over current relay KR880001149B1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
KR1019850002996A KR880001149B1 (en) 1985-05-02 1985-05-02 Over current relay
EP86900857A EP0221185B1 (en) 1985-05-02 1986-01-21 Electronic overcurrent relay
PCT/KR1986/000003 WO1986006562A1 (en) 1985-05-02 1986-01-21 Electronic overcurrent relay
US07/256,138 US4879626A (en) 1984-09-01 1988-10-07 Overload relay with adjustable threshold indicator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1019850002996A KR880001149B1 (en) 1985-05-02 1985-05-02 Over current relay

Publications (2)

Publication Number Publication Date
KR860009450A KR860009450A (en) 1986-12-23
KR880001149B1 true KR880001149B1 (en) 1988-07-01

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Application Number Title Priority Date Filing Date
KR1019850002996A KR880001149B1 (en) 1984-09-01 1985-05-02 Over current relay

Country Status (1)

Country Link
KR (1) KR880001149B1 (en)

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KR860009450A (en) 1986-12-23

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