CN210724184U - Teaching experiment equipment overload protection circuit - Google Patents
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Abstract
一种教学实验设备过载保护电路,包括电阻R1，电阻R1一端连接整流桥1引脚、继电器K1公共触点，K1常闭触点连接用电设备正极，用电设备负极连接交流电源AC1N端；电阻R1另一端连接AC1L端、整流桥3引脚，整流桥2引脚连接光电耦合器U1的光耦二极管阳极，光耦二极管阴极连接整流桥4引脚，U1的光耦三极管集电极连接开关按钮S1一端、单向可控硅Q1阳极，S1另一端连接直流电源VCC端，Q1门极连接U1的光耦三极管发射极，Q1阴极连接电阻R2、R3、继电器K1线圈一端、二极管D1阴极，电阻R2另一端连接蜂鸣器LS1一端，LS1另一端连接GND端、红色发光二极管L1阴极、D1阳极和K1线圈另一端，L1阳极和电阻R3另一端连接；本实用新型具有线路简单、成本低等优点。
An overload protection circuit for teaching experimental equipment, comprising a resistor R1, one end of the resistor R1 is connected to a pin 1 of a rectifier bridge and a common contact of a relay K1, the normally closed contact of K1 is connected to the positive pole of an electrical device, and the negative pole of the electrical device is connected to the AC1N terminal of an AC power supply; The other end of the resistor R1 is connected to the AC1L terminal and the 3 pin of the rectifier bridge, the 2 pin of the rectifier bridge is connected to the anode of the optocoupler diode of the optocoupler U1, the cathode of the optocoupler diode is connected to the 4th pin of the rectifier bridge, and the collector of the optocoupler transistor of U1 is connected to the switch One end of the button S1, the anode of the one-way thyristor Q1, the other end of S1 is connected to the VCC end of the DC power supply, the gate of Q1 is connected to the emitter of the optocoupler triode of U1, the cathode of Q1 is connected to the resistors R2, R3, one end of the coil of the relay K1, and the cathode of the diode D1. The other end of the resistor R2 is connected to one end of the buzzer LS1, the other end of LS1 is connected to the GND end, the cathode of the red light-emitting diode L1, the anode of D1 and the other end of the K1 coil, and the anode of L1 is connected to the other end of the resistor R3; the utility model has the advantages of simple circuit and low cost. Etc.
Description
技术领域technical field
本实用新型属于电路保护技术领域，具体涉及一种教学实验设备过载保护电路。The utility model belongs to the technical field of circuit protection, in particular to an overload protection circuit for teaching experimental equipment.
背景技术Background technique
电工电子实验设备作为实践教学的重要工具，已经在高等院校、职校、职业技术学院等高校有了广泛的应用。但是由于设备老化、人员操作不规范等原因，设备在使用过程中也慢慢的显示出了部分弊端，例如，学生在操作实验时，有时会由于误操作，造成设备发生过载短路等情况，如果没有保护措施，数学设备很快就会损坏，需要进行维修或更换。目前，学校使用的电工电子实验设备基本上都设有短路和过载保护电路，但是该种方式通常是通过保险丝来实现的，该方法虽然具有线路简单、安装方便等优点，但是当发生过载事故时需要进行频繁的更换保险丝，更换成本较高。此外，该方法缺少相应的过载提醒电路，在发生过载事故时无法及时的获悉过载事故，从而造成检修时间的延误。As an important tool for practical teaching, electrical and electronic experimental equipment has been widely used in colleges and universities, vocational schools, vocational and technical colleges and other colleges and universities. However, due to the aging of the equipment and the non-standard operation of the personnel, the equipment has gradually shown some drawbacks during the use process. For example, when students operate experiments, sometimes the equipment is overloaded and short-circuited due to misoperation. Without protection, math equipment can quickly break down and require repair or replacement. At present, the electrical and electronic experimental equipment used in schools is basically equipped with short-circuit and overload protection circuits, but this method is usually realized by fuses. Frequent replacement of the fuse is required, and the replacement cost is high. In addition, this method lacks a corresponding overload reminder circuit, and cannot be informed of an overload accident in time when an overload accident occurs, thereby causing a delay in maintenance time.
发明内容SUMMARY OF THE INVENTION
为了克服上述现有技术的缺点，本实用新型的目的在于提供一种教学实验设备过载保护电路，在试验设备过载时通过声光报警的方式进行过载保护，具有成本低、安全性能高等优点。In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present utility model is to provide an overload protection circuit for teaching experimental equipment, which can carry out overload protection by means of sound and light alarm when the experimental equipment is overloaded, and has the advantages of low cost and high safety performance.
为了达到上述目的，本实用新型采取的技术方案为：In order to achieve the above purpose, the technical scheme adopted by the present utility model is:
一种教学实验设备过载保护电路,包括电阻R1，电阻R1的一端连接整流桥BR1的第1引脚、继电器K1的公共触点端，继电器K1的常闭触点端连接用电设备的正极端，用电设备的负极端连接交流电源AC1的N端；An overload protection circuit for teaching experimental equipment, comprising a resistor R1, one end of the resistor R1 is connected to the first pin of the rectifier bridge BR1, the common contact end of the relay K1, and the normally closed contact end of the relay K1 is connected to the positive end of the electrical equipment , the negative terminal of the electrical equipment is connected to the N terminal of the AC power supply AC1;
电阻R1的另一端连接交流电源AC1的L端、整流桥BR1的第3引脚，整流桥BR1的第2引脚连接光电耦合器U1的光耦二极管的阳极端，光耦二极管的阴极端连接整流桥BR1的第4引脚，光电耦合器U1的光耦三极管的集电极端连接开关按钮S1的一端、单向可控硅Q1的阳极端，开关按钮S1的另一端连接直流电源VCC端，单向可控硅Q1的门极端连接光电耦合器U1的光耦三极管的发射极端，单向可控硅Q1的阴极端连接电阻R2、电阻R3、继电器K1线圈的一端、二极管D1的阴极端，电阻R2的另一端连接蜂鸣器LS1的一端，蜂鸣器LS1的另一端连接GND端、红色发光二极管L1的阴极端、二极管D1的阳极端和继电器K1线圈的另一端，红色发光二极管L1的阳极端和电阻R3另一端连接。The other end of the resistor R1 is connected to the L end of the AC power supply AC1, the third pin of the rectifier bridge BR1, the second pin of the rectifier bridge BR1 is connected to the anode end of the optocoupler diode of the optocoupler U1, and the cathode end of the optocoupler diode is connected. The fourth pin of the rectifier bridge BR1, the collector end of the optocoupler triode of the photocoupler U1 is connected to one end of the switch button S1, the anode end of the one-way thyristor Q1, and the other end of the switch button S1 is connected to the VCC end of the DC power supply, The gate terminal of the one-way thyristor Q1 is connected to the emitter terminal of the optocoupler triode of the photocoupler U1, and the cathode terminal of the one-way thyristor Q1 is connected to the resistor R2, the resistor R3, one end of the relay K1 coil, and the cathode terminal of the diode D1. The other end of the resistor R2 is connected to one end of the buzzer LS1, the other end of the buzzer LS1 is connected to the GND end, the cathode end of the red light-emitting diode L1, the anode end of the diode D1 and the other end of the relay K1 coil, and the other end of the red light-emitting diode L1 The anode end is connected to the other end of the resistor R3.
所述的直流电源VCC为6V,蜂鸣器LS1为有源蜂鸣器，工作电压为3.3V。The DC power supply VCC is 6V, the buzzer LS1 is an active buzzer, and the working voltage is 3.3V.
所述的继电器K1为5脚继电器，产品型号为SRD-05VDC-SL-C，供电电压为5V。The relay K1 is a 5-pin relay, the product model is SRD-05VDC-SL-C, and the power supply voltage is 5V.
所述的光电耦合器U1的型号为PC817，单向可控硅Q1的型号为2N1595，二极管D1为整流二极管，型号为IN4005。The model of the optocoupler U1 is PC817, the model of the one-way thyristor Q1 is 2N1595, the diode D1 is a rectifier diode, and the model is IN4005.
所述的电阻R1为高精度采样电阻，阻值大小为1.4V/用电设备的最大电流。The resistor R1 is a high-precision sampling resistor, and the resistance value is 1.4V/the maximum current of the electrical equipment.
所述的电阻R2、R3分别为200Ω、300Ω。The resistances R2 and R3 are respectively 200Ω and 300Ω.
本实用新型的有益效果：The beneficial effects of the present utility model:
1、通过采样电阻R1实现过载检测，发生过载事故时，能够及时的通过继电器K1切断供电电源输入，相比较传统更换保险丝的工作方式，检测成本低，工作效率高。1. The overload detection is realized through the sampling resistor R1. When an overload accident occurs, the power supply input can be cut off through the relay K1 in time. Compared with the traditional working method of replacing the fuse, the detection cost is low and the work efficiency is high.
2、通过有源蜂鸣器LS1、红色发光二极管L1声光报警的方式进行过载提醒，从而能够快速提醒用户在过载时及时的进行事故处理，避免过载事故对用电设备造成损坏。2. The overload reminder is carried out by means of the active buzzer LS1 and the red light-emitting diode L1 sound and light alarm, so that the user can be quickly reminded to deal with the accident in time when the overload occurs, so as to avoid damage to the electrical equipment caused by the overload accident.
3、电路具有线路结构简单、可靠性高、成本低、可重复利用等优点。3. The circuit has the advantages of simple circuit structure, high reliability, low cost, and reusability.
附图说明Description of drawings
图1为本实用新型的电路示意图。FIG. 1 is a schematic circuit diagram of the utility model.
图2为用电设备正常工作时的电流流向示意图。FIG. 2 is a schematic diagram of the current flow when the electrical equipment is working normally.
图3为用电设备发生过载事故时，单向可控硅触发时的瞬间电流流向示意图。Figure 3 is a schematic diagram of the instantaneous current flow when the one-way thyristor is triggered when an overload accident occurs in the electrical equipment.
图4为用电设备发生过载事故时，单向可控硅触发后未关断时的瞬间电流流向示意图。Figure 4 is a schematic diagram of the instantaneous current flow when the one-way thyristor is triggered and not turned off when an overload accident occurs in the electrical equipment.
具体实施方式Detailed ways
下面结合附图和实施例对本实用新型进一步说明。The present utility model will be further described below in conjunction with the accompanying drawings and embodiments.
参照图1，一种教学实验设备过载保护电路,包括电阻R1，电阻R1的一端连接整流桥BR1的第1引脚、继电器K1的公共触点端，继电器K1的常闭触点端连接用电设备的正极端，用电设备的负极端连接交流电源AC1的N端；Referring to Figure 1, an overload protection circuit for teaching experimental equipment, including a resistor R1, one end of the resistor R1 is connected to the first pin of the rectifier bridge BR1, the common contact end of the relay K1, and the normally closed contact end of the relay K1 is connected to electricity. The positive terminal of the equipment and the negative terminal of the electrical equipment are connected to the N terminal of the AC power supply AC1;
电阻R1的另一端连接交流电源AC1的L端、整流桥BR1的第3引脚，整流桥BR1的第2引脚连接光电耦合器U1的光耦二极管的阳极端，光耦二极管的阴极端连接整流桥BR1的第4引脚，光电耦合器U1的光耦三极管的集电极端连接开关按钮S1的一端、单向可控硅Q1的阳极端，开关按钮S1的另一端连接直流电源VCC端，单向可控硅Q1的门极端连接光电耦合器U1的光耦三极管的发射极端，单向可控硅Q1的阴极端连接电阻R2、电阻R3、继电器K1线圈的一端、二极管D1的阴极端，电阻R2的另一端连接蜂鸣器LS1的一端，蜂鸣器LS1的另一端连接GND端、红色发光二极管L1的阴极端、二极管D1的阳极端和继电器K1线圈的另一端，红色发光二极管L1的阳极端和电阻R3另一端连接。The other end of the resistor R1 is connected to the L end of the AC power supply AC1, the third pin of the rectifier bridge BR1, the second pin of the rectifier bridge BR1 is connected to the anode end of the optocoupler diode of the optocoupler U1, and the cathode end of the optocoupler diode is connected. The fourth pin of the rectifier bridge BR1, the collector end of the optocoupler triode of the photocoupler U1 is connected to one end of the switch button S1, the anode end of the one-way thyristor Q1, and the other end of the switch button S1 is connected to the VCC end of the DC power supply, The gate terminal of the one-way thyristor Q1 is connected to the emitter terminal of the optocoupler triode of the photocoupler U1, and the cathode terminal of the one-way thyristor Q1 is connected to the resistor R2, the resistor R3, one end of the relay K1 coil, and the cathode terminal of the diode D1. The other end of the resistor R2 is connected to one end of the buzzer LS1, and the other end of the buzzer LS1 is connected to the GND end, the cathode end of the red light-emitting diode L1, the anode end of the diode D1 and the other end of the relay K1 coil. The anode end is connected to the other end of the resistor R3.
所述的直流电源VCC为6V,蜂鸣器LS1为有源蜂鸣器，工作电压为3.3V。The DC power supply VCC is 6V, the buzzer LS1 is an active buzzer, and the working voltage is 3.3V.
所述的继电器K1为5脚继电器，产品型号为SRD-05VDC-SL-C，供电电压为5V。The relay K1 is a 5-pin relay, the product model is SRD-05VDC-SL-C, and the power supply voltage is 5V.
所述的光电耦合器U1的型号为PC817，单向可控硅Q1的型号为2N1595，二极管D1为整流二极管，型号为IN4005。The model of the optocoupler U1 is PC817, the model of the one-way thyristor Q1 is 2N1595, the diode D1 is a rectifier diode, and the model is IN4005.
所述的电阻R1为高精度采样电阻，阻值大小为1.4V/用电设备的最大电流。The resistor R1 is a high-precision sampling resistor, and the resistance value is 1.4V/the maximum current of the electrical equipment.
所述的电阻R2、R3分别为200Ω、300Ω。The resistances R2 and R3 are respectively 200Ω and 300Ω.
本实用新型的工作原理为：The working principle of the utility model is:
如图1、图2所示，当接通交流电源AC1，按下开关按钮S1，用电设备正常工作时，电阻R1进行电流采样，此时电阻R1两端电压小于1.4V(经过整流桥整流后光电耦合器U1的光耦二极管两端电压小于1.2V)，由于光电耦合器U1的最低导通电压为1.2V，此时光电耦合器U1的光耦二极管不导通，使得光耦三极管停止导通，继电器K1线圈无电流通过，开关保持在常闭触点端，此时电流从交流电源AC1的L端流经电阻R1、继电器K1常闭触点和用电设备后流入交流电源AC1的N端，从而为用电设备提供电源输入，用电设备正常工作。As shown in Figure 1 and Figure 2, when the AC power supply AC1 is turned on, the switch button S1 is pressed, and the electrical equipment is working normally, the resistor R1 performs current sampling, and the voltage across the resistor R1 is less than 1.4V (after rectification by the rectifier bridge). The voltage across the optocoupler diode of the rear optocoupler U1 is less than 1.2V), since the minimum conduction voltage of the optocoupler U1 is 1.2V, the optocoupler diode of the optocoupler U1 is not conducting at this time, which makes the optocoupler transistor stop. When it is turned on, no current flows through the coil of relay K1, and the switch remains at the normally closed contact terminal. At this time, the current flows from the L terminal of the AC power supply AC1 through the resistor R1, the normally closed contact of the relay K1 and the electrical equipment, and then flows into the AC power supply AC1. N terminal, so as to provide power input for the electrical equipment, and the electrical equipment works normally.
如图1、图3所示，当输入电流过大发生过载事故时，由于电阻R1两端电压大于1.4V，光电耦合器U1的光耦二极管两端电压大于1.2V，此时光电耦合器U1的光耦二极管导通，从而使得光电耦合器U1的光耦三极管也导通，此时电流从直流电源VCC端流经光耦三极管后流入单向可控硅Q1的门极端(经过光耦三极管分压后门极端电压大约为4.8V)，此时单向可控硅Q1导通，电流从直流电源VCC端流经单向可控硅Q1后分流成三路，一路电流流经电阻R2、蜂鸣器LS1后流入GND端，一路电流流经电阻R3、红色发光二极管L1后流入GND端，另有一路电流流经继电器K1线圈后流入GND端，由于此时继电器线圈两端电压大约为5V左右，继电器线圈得电，使得常开触点得电，常闭触点失电，开关吸合在常开触点端。切断了交流电源AC1的输入，用电设备停止工作。同时，由于蜂鸣器LS1、红色发光二极管L1有电流流过，蜂鸣器LS1进行鸣叫，红色发光二极管L1进行发光，通过声光报警的方式提醒用户发生过载事故，从而让用户及时的进行事故处理。As shown in Figure 1 and Figure 3, when the input current is too large and an overload accident occurs, since the voltage across the resistor R1 is greater than 1.4V, the voltage across the optocoupler diode of the optocoupler U1 is greater than 1.2V. At this time, the optocoupler U1 The optocoupler diode is turned on, so that the optocoupler transistor of the optocoupler U1 is also turned on. At this time, the current flows from the VCC terminal of the DC power supply through the optocoupler transistor and then flows into the gate terminal of the one-way thyristor Q1 (through the optocoupler transistor). After the voltage divider, the gate terminal voltage is about 4.8V), at this time, the one-way thyristor Q1 is turned on, and the current flows from the VCC terminal of the DC power supply through the one-way thyristor Q1 and is divided into three paths, one current flows through the resistor R2, the bee The buzzer LS1 flows into the GND terminal, one current flows through the resistor R3 and the red light-emitting diode L1 and then flows into the GND terminal, and another current flows through the relay K1 coil and then flows into the GND terminal, because the voltage across the relay coil is about 5V at this time. , the relay coil is energized, so that the normally open contact is energized, the normally closed contact is de-energized, and the switch is pulled in at the normally open contact end. The input of AC power supply AC1 is cut off, and the electrical equipment stops working. At the same time, since the buzzer LS1 and the red light-emitting diode L1 have current flowing, the buzzer LS1 beeps, and the red light-emitting diode L1 emits light, reminding the user of an overload accident by sound and light alarm, so that the user can carry out the accident in time. deal with.
如图1、图4所示，交流电源AC1的电源停止电源输入后，电阻R1两端没有电压输出，光电耦合器U1的光耦二极管关断，光耦三极管关断，由于单向可控硅Q1的关断特性，单向可控硅Q1继续保持开通状态，因而使得继电器K1继续吸合，红色发光二极管L1继续发光，蜂鸣器LS1继续鸣叫，当断开交流电源AC1，按起开关按钮S1，单向可控硅Q1停止导通，继电器K1线圈失电，继电器常开触点失电，使得继电器开关回复到常闭触点端，同时由于蜂鸣器LS1、红色发光二极管L1没有电流流过，蜂鸣器LS1停止鸣叫，红色发光二极管L1停止发光。过载故障排除后，接通交流电源AC1，按下开关按钮S1后，就可进行下一次过载保护。本实用新型具有成本低、操作便捷、可重复利用等优点。As shown in Figure 1 and Figure 4, after the AC power supply AC1 stops the power input, there is no voltage output across the resistor R1, the optocoupler diode of the optocoupler U1 is turned off, and the optocoupler transistor is turned off. The turn-off characteristic of Q1, the one-way thyristor Q1 continues to be in the open state, thus making the relay K1 continue to pull in, the red light-emitting diode L1 continues to emit light, and the buzzer LS1 continues to sound. When the AC power supply AC1 is disconnected, press the switch button. S1, the one-way thyristor Q1 stops conducting, the coil of the relay K1 is de-energized, and the normally open contact of the relay is de-energized, so that the relay switch returns to the normally closed contact end, and at the same time, there is no current due to the buzzer LS1 and the red light-emitting diode L1. Flowing through, the buzzer LS1 stops beeping, and the red LED L1 stops emitting light. After the overload fault is eliminated, connect the AC power supply AC1, and press the switch button S1 to perform the next overload protection. The utility model has the advantages of low cost, convenient operation, reusability and the like.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922239594.2U CN210724184U (en) | 2019-12-14 | 2019-12-14 | Teaching experiment equipment overload protection circuit |
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| CN201922239594.2U CN210724184U (en) | 2019-12-14 | 2019-12-14 | Teaching experiment equipment overload protection circuit |
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| CN210724184U true CN210724184U (en) | 2020-06-09 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112769094A (en) * | 2020-12-28 | 2021-05-07 | 苏州工业园区天和仪器有限公司 | Alternating current overload detection protection circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112769094A (en) * | 2020-12-28 | 2021-05-07 | 苏州工业园区天和仪器有限公司 | Alternating current overload detection protection circuit |
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Granted publication date: 20200609 |