An electrical explosion-proof isolation protection device

Abstract

The invention discloses an explosion-proof isolation protection device for electricity use, comprising an input overcurrent protection switch, an isolation transformer, a current transformer, a power relay, an intelligent protection module, and an output overcurrent protection switch. The input end of the input overcurrent protection switch is used to connect to the mains, the two output pins of the input overcurrent protection switch are respectively connected to the two pins on the primary side of the isolation transformer, the first pin on the secondary side of the isolation transformer is connected to the first terminal of the normally closed contact of the power relay, the current transformer is sleeved between the first pin on the secondary side of the isolation transformer and the first terminal of the normally closed contact of the power relay, the second terminal of the normally closed contact of the power relay is connected to the first terminal of the normally closed contact of the first phase line of the output overcurrent protection switch, and the first terminal of the normally closed contact of the second phase line of the output overcurrent protection switch is connected to the second pin on the secondary side of the isolation transformer.

Description

Technical Field

[0001] The invention relates to the technical field of power protection devices, and in particular to an explosion-proof isolation protection device for power consumption. Background Art

[0002] At present, electrical appliances are essential and efficient tools. However, in some flammable and explosive occasions, such as gas stations, flammable oil and gas processing occasions, and even kitchens with intensive gas release, using electrical appliances is a very dangerous thing. However, electrical appliances are necessary tools, so the current situation is very dangerous. The limited use of electrical appliances in flammable and explosive occasions has also caused great inconvenience. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides an electrical explosion-proof isolation protection device.

[0004] An explosion-proof isolation protection device for electricity, including: an input overcurrent protection switch, an isolation transformer, a current transformer, a power relay, an intelligent protection module, and an output overcurrent protection switch, wherein the input end of the input overcurrent protection switch is used to connect to the mains, the output overcurrent protection switch is a mechanical mains / protection switching switch, the first input side of the output overcurrent protection switch is a two-phase connection pin of the mains, and the second input side of the output overcurrent protection switch is a two-phase connection pin of the protection circuit;

[0005] The output side of the input overcurrent protection switch is divided into two paths: the first path: the two pins on the output side of the input overcurrent protection switch are connected one by one to the two-phase line pins of the first mains power line on the input side of the output overcurrent protection switch;

[0006] Second path: the two pins on the output side of the input overcurrent protection switch are connected to the two pins on the primary side of the isolation transformer in a one-to-one correspondence, the first pin on the secondary side of the isolation transformer is connected to the input side terminal of the normally closed contact of the power relay, the current transformer is inserted into the electrical connection line between the first pin on the secondary side of the isolation transformer and the input side terminal of the normally closed contact of the power relay, the output side terminal of the normally closed contact of the power relay is connected to the first phase line terminal of the two pins of the second protection circuit on the input side of the output overcurrent protection switch, and the second phase line terminal of the two pins of the second protection circuit on the input side of the output overcurrent protection switch is connected to the second pin on the secondary side of the isolation transformer;

[0007] The two ends of the current transformer are connected to the two input terminals of the intelligent protection module in a one-to-one correspondence; the control signal output end of the intelligent protection module is connected to the first end of the coil of the power relay, and the second end of the coil of the power relay is grounded.

[0008] Furthermore, the electrical explosion-proof isolation protection device, wherein: the intelligent protection module includes an intelligent ammeter, a first intermediate relay KA1, a second intermediate relay KA2, a first time relay KT1, a second time relay KT2, and two signal input terminals of the intelligent ammeter are connected to the two ends of the current transformer in a one-to-one correspondence;

[0009] The short-circuit signal output end of the intelligent ammeter is connected to the first end of the coil of the second intermediate relay KA2, the second end of the coil of the second intermediate relay KA2 is grounded, the second end of the normally open contact of the second intermediate relay KA2, pin 4, is connected to a 12V power supply, the first end of the normally open contact of the second intermediate relay KA2, pin 6, is connected to the first end of the coil of the power relay, and the second end of the coil of the power relay is grounded;

[0010] The overload signal output end of the intelligent ammeter is connected to the first end of the coil of the first time relay, and the second end of the coil of the first time relay is grounded; the first end of the normally open contact of the first time relay is connected to the 12V power supply, and the second end of the normally open contact of the first time relay is divided into three paths: the first path is connected to the first end of the coil of the second time relay, and the second end of the coil of the second time relay is grounded; the second path is connected to the first end of the normally closed delay jump contact of the second time relay, and the second end of the normally closed delay jump contact of the second time relay is connected to the first end of the coil of the first intermediate relay, and the second end of the coil of the first intermediate relay is grounded; the third path is connected to the first end of the first normally open contact of the first intermediate relay, and the second end of the first normally open contact of the first intermediate relay is simultaneously connected to the 12V power supply and the second end of the normally open contact of the second intermediate relay, and the first end of the normally open contact of the second intermediate relay is connected to the first end of the coil of the power relay;

[0011] A first end of the second normally open contact of the first intermediate relay is connected to a 12V power supply, and a second end of the second normally open contact of the first intermediate relay is connected to a first end of a coil of a power relay.

[0012] Furthermore, the electrical explosion-proof isolation protection device, wherein: also includes an alarm module, the alarm module includes an insulation resistance measuring instrument H2 and an alarm horn;

[0013] The signal acquisition input end of the insulation resistance measuring instrument H2 includes two pins, and the two pins of the signal acquisition input end of the insulation resistance measuring instrument H2 are connected one by one with the two-phase pins of the second protection circuit on the input side of the output overcurrent protection switch;

[0014] The two pins of the alarm signal output terminal of the insulation resistance measuring instrument H2 are connected to the two power supply input terminals of the alarm horn correspondingly.

[0015] Furthermore, the electrical explosion-proof isolation protection device, wherein: also includes an over-temperature protection device, the over-temperature protection device includes a comparator, a reference voltage circuit, a thermistor, a temperature signal circuit, and an over-temperature alarm circuit;

[0016] The reference voltage circuit includes a second resistor, a third resistor, an eighth resistor, and a ninth resistor. The second resistor and the third resistor are connected in parallel to form a first parallel circuit. The eighth resistor and the ninth resistor are connected in parallel to form a second parallel circuit. The first end of the first parallel circuit is connected to a 12V power supply. The second end of the first parallel circuit is connected in series to the first end of the second parallel circuit. The second end of the second parallel circuit is grounded. The middle point of the first parallel circuit and the second parallel circuit is connected to the reference voltage input end of the comparator.

[0017] The temperature signal circuit includes a fourth resistor, a sixth resistor, and a seventh resistor, and the sixth and seventh resistors are connected in parallel to form a third parallel circuit; the first end of the thermistor is connected to a 12V power supply, the second end of the thermistor is connected to a first end of a fourth resistor R4, the second end of the fourth resistor R4 is connected to a first end of the third parallel circuit, and the second end of the third parallel circuit is grounded; the middle point between the fourth resistor R4 and the first end of the third parallel circuit is connected to the temperature signal input end of the comparator;

[0018] The over-temperature alarm circuit includes a fifth resistor, a first resistor, a first transistor, an over-temperature alarm buzzer, and a first diode. The first transistor is a PNP transistor. The first resistor is connected between the emitter and the base of the first transistor. The emitter of the first transistor is connected to a 12V power supply. The base of the first transistor is connected in series with the fifth resistor and then connected to the alarm signal output end of the comparator. The collector of the first transistor is connected to the first end of the over-temperature alarm buzzer, and the second end of the over-temperature alarm buzzer is grounded; the positive electrode of the first diode is connected to the second end of the over-temperature alarm buzzer, and the negative electrode of the first diode is connected to the first end of the over-temperature alarm buzzer; the collector of the first transistor is also connected to the over-temperature signal input end of the intelligent protection module, and the over-temperature signal input end is the first end of the coil of the first time relay.

[0019] Furthermore, in the electrical explosion-proof isolation protection device, the comparator model is LM358.

[0020] Furthermore, the electrical explosion-proof isolation protection device, wherein: also includes a heat dissipation circuit, the heat dissipation circuit includes a heat dissipation fan and a first switch, the first end of the first switch is connected to a 12V power supply, the second end of the first switch is connected to a first terminal of the heat dissipation fan, and the second terminal of the heat dissipation fan is grounded; the wind direction of the heat dissipation fan is set toward the isolation transformer.

[0021] The invention provides an explosion-proof isolation protection device for electricity. The output signal after voltage transformation by the isolation transformer is transmitted to the intelligent protection module after detection by the current transformer. The intelligent protection module controls the power relay. The on-off of the normally closed contact of the power relay controls the on-off of the main circuit loop, thereby realizing effective power off. If any line on the output side of the isolation transformer is touched by mistake, there is no harm to the human body due to the effect of the isolation transformer. When an abnormality occurs and the current is too large to generate sparks, the circuit will be disconnected before the arc spark expands, and the arc spark will be limited to the minimum range to prevent fire. The device can be connected in series in the circuit to realize this function. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a circuit diagram of an electrical explosion-proof isolation protection device. DETAILED DESCRIPTION

[0023] The present invention provides an electrical explosion-proof isolation protection device, such as Figure 1 As shown, it includes an input overcurrent protection switch S2, an isolation transformer T1, a current transformer TA, a power relay K1, an intelligent protection module, and an output overcurrent protection switch S3. The input end of the input overcurrent protection switch S2 is connected to the two-phase mains (L phase and N phase) through a terminal block H1. The input overcurrent protection switch S2 is a two-phase linkage switch;

[0024] The output overcurrent protection switch is a mechanical AC power / protection switch. The first input side of the output overcurrent protection switch is the two-phase AC power pin, and the second input side of the output overcurrent protection switch is the two-phase protection circuit pin;

[0025] The output side of the input overcurrent protection switch is divided into two paths:

[0026] First route: The two pins on the output side of the input overcurrent protection switch S2 are connected one by one to the two-phase line pins of the first route of the mains power on the input side of the output overcurrent protection switch S3: pin 2 and pin 4;

[0027] Second path: the two pins on the output side of the input overcurrent protection switch S2 are connected to the two pins on the primary side of the isolation transformer T1 in one-to-one correspondence, the first pin on the secondary side of the isolation transformer T1 is connected to the input side terminal 1 pin of the normally closed contact of the power relay K1, the current transformer TA is sleeved outside the electrical connection line between the first pin on the secondary side of the isolation transformer T1 and the input side terminal 1 pin of the normally closed contact of the power relay K1, the output side terminal 3 pin of the normally closed contact of the power relay K1 is connected to the first phase line terminal 6 pin of the two pins of the second protection circuit on the input side of the output overcurrent protection switch S3, and the second phase line terminal 3 pin of the two pins of the second protection circuit on the input side of the output overcurrent protection switch S3 is connected to the second pin of the secondary side of the isolation transformer T1;

[0028] The two ends of the current transformer TA are connected to the two input terminals of the intelligent protection module in a one-to-one correspondence; the control signal output end of the intelligent protection module is connected to the first end 5 pin of the coil of the power relay K1, and the second end 4 pin of the coil of the power relay K1 is grounded.

[0029] The intelligent protection module includes an intelligent ammeter SM, a first intermediate relay KA1, a second intermediate relay KA2, a first time relay KT1, and a second time relay KT2. The two signal input terminals of the intelligent ammeter SM are connected to the two ends of the current transformer TA in a one-to-one correspondence.

[0030] The short-circuit signal output terminal pin 5 of the smart ammeter SM is connected to the first end pin 8 of the coil of the second intermediate relay KA2, the second end pin 7 of the coil of the second intermediate relay KA2 is grounded, the second end pin 4 of the normally open contact of the second intermediate relay KA2 is connected to the 12V power supply, the first end pin 6 of the normally open contact of the second intermediate relay KA2 is connected to the first end pin 5 of the coil of the power relay K1, and the second end pin 4 of the coil of the power relay K1 is grounded;

[0031] The overload signal output terminal 14-pin of the smart ammeter SM is connected to the first end 14-pin of the coil of the first time relay KT1, and the second end 13-pin of the coil of the first time relay KT1 is grounded; the first end 5-pin of the normally open contact of the first time relay KT1 is connected to the 12V power supply, and the second end 9-pin of the normally open contact of the first time relay KT1 is divided into three paths: the first path is connected to the first end 14-pin of the coil of the second time relay KT2, and the second end 13-pin of the coil of the second time relay KT2 is grounded; the second path is connected to the first end 4-pin of the normally closed delay jump contact of the second time relay KT2 The second end 12-pin of the normally closed delay jump contact of the second time relay KT2 is connected to the first end 8-pin of the coil of the first intermediate relay KA1, and the second end 7-pin of the coil of the first intermediate relay KA1 is grounded; the third way is connected to the first end 6-pin of the first normally open contact of the first intermediate relay KA1, and the second end 4-pin of the first normally open contact of the first intermediate relay KA1 is simultaneously connected to the 12V power supply and the second end 4-pin of the normally open contact of the second intermediate relay KA2, and the first end 6-pin of the normally open contact of the second intermediate relay KA2 is connected to the first end 5-pin of the coil of the power relay K1;

[0032] Pin 3 of the first end of the second normally open contact of the first intermediate relay KA1 is connected to the 12V power supply, and pin 5 of the second normally open contact of the first intermediate relay KA1 is connected to pin 5 of the first end of the coil of the power relay K1.

[0033] Figure 1 The electrical explosion-proof isolation protection device shown also includes an alarm module, which includes an insulation resistance measuring instrument H2 and an alarm horn;

[0034] The signal acquisition input end of the insulation resistance measuring instrument H2 includes two pins 3 and 4, and the two pins 3 and 4 of the signal acquisition input end of the insulation resistance measuring instrument H2 are connected to the two-phase pins 6 and 3 of the second protection circuit on the input side of the output overcurrent protection switch S3 in a one-to-one correspondence;

[0035] The two pins 6 and 8 of the alarm signal output terminal of the insulation resistance measuring instrument H2 are connected to the two power supply input terminals of the alarm speaker BZ1 correspondingly.

[0036] Figure 1 The electrical explosion-proof isolation protection device shown also includes an over-temperature protection device, which includes a comparator U1, a reference voltage circuit, a thermistor, a temperature signal circuit, and an over-temperature alarm circuit; the thermistor is connected to the socket P3;

[0037] The reference voltage circuit includes a second resistor R2, a third resistor R3, an eighth resistor R8, and a ninth resistor R9. The second resistor R2 and the third resistor R3 are connected in parallel to form a first parallel circuit. The eighth resistor R8 and the ninth resistor R9 are connected in parallel to form a second parallel circuit. The first end of the first parallel circuit is connected to a 12V power supply. The second end of the first parallel circuit is connected in series to the first end of the second parallel circuit. The second end of the second parallel circuit is grounded. The middle point of the first parallel circuit and the second parallel circuit is connected to the reference voltage input terminal 3 of the comparator U1.

[0038] The temperature signal circuit includes a fourth resistor R4, a sixth resistor R6, and a seventh resistor R7. The sixth and seventh resistors R6 and R7 are connected in parallel to form a third parallel circuit. The first end of the thermistor is connected to a 12V power supply, the second end of the thermistor is connected to a first end of the fourth resistor R4, the second end of the fourth resistor R4 is connected to a first end of the third parallel circuit, and the second end of the third parallel circuit is grounded. The middle node between the fourth resistor R4 and the first end of the third parallel circuit is connected to the temperature signal input terminal 2 pin of the comparator U1.

[0039] The over-temperature alarm circuit includes a fifth resistor R5, a first resistor R1, a first transistor Q1, an over-temperature alarm buzzer BZ2, and a first diode D1. The first transistor Q1 is a PNP transistor. The first resistor R1 is connected between the emitter and the base of the first transistor Q1. The emitter of the first transistor Q1 is connected to a 12V power supply. The base of the first transistor Q1 is connected in series with the fifth resistor R5 and then connected to the alarm signal output terminal 1 pin of the comparator U1. The collector of the first transistor Q1 is connected to the first end of the over-temperature alarm buzzer BZ2, and the second end of the over-temperature alarm buzzer BZ2 is grounded; the positive electrode of the first diode D1 is connected to the second end of the over-temperature alarm buzzer BZ2, and the negative electrode of the first diode D1 is connected to the first end of the over-temperature alarm buzzer BZ2; the collector of the first transistor Q1 is also connected to the over-temperature signal input terminal of the intelligent protection module, and the over-temperature signal input terminal is the first end 14 pin of the coil of the first time relay KT1 (connected through the NET1 point).

[0040] Figure 1 The electrical explosion-proof isolation protection device shown also includes a heat dissipation circuit, which includes a heat dissipation fan F and a first switch S1. The first end of the first switch S1 is connected to a 12V power supply, the second end of the first switch S1 is connected to a first terminal of the heat dissipation fan F, and the second terminal of the heat dissipation fan is grounded; the wind direction of the heat dissipation fan F is set toward the isolation transformer, which is used to dissipate heat and cool the isolation transformer.

[0041] Figure 1 The electrical explosion-proof isolation protection device shown also includes an arc extinguishing circuit, which includes an arc extinguisher, and the arc extinguisher is connected in series to the first phase line on the output side of the output overcurrent protection switch S3.

[0042] In this embodiment, the comparator U1 is a LM358.

[0043] The present technical solution also provides a backup power supply PW, and the two output pins of the backup power supply PW are connected to the two output pins of the input overcurrent protection switch S2 in a one-to-one correspondence. The two output pins of the backup power supply PW are also connected to the two phase pins of the second protection circuit on the input side of the output overcurrent protection switch S3 in a one-to-one correspondence. The phase line connection relationship between the two output pins of the backup power supply PW and the two output pins of the input overcurrent protection switch S2 and the two phase pins of the second protection circuit on the input side of the output overcurrent protection switch S3 is consistent with the phase line connection relationship in the aforementioned circuit that maintains the connection between the output side of the input overcurrent protection switch S2 and the two phase pins of the second protection circuit on the input side of the output overcurrent protection switch S3.

[0044] The specific work of this technical solution is as follows:

[0045] Switch the input side of the output overcurrent protection switch S3 to the second protection circuit, and the main circuit is energized. The electric energy is sent from the input overcurrent protection switch S2 to the isolation transformer T1, and the main power is isolated. The electric energy passes through the current transformer TA, the power relay K1, and then the output overcurrent protection switch S3 and the arc extinguishing module, and is output through the terminal H1. Due to the action of the isolation transformer T1, if a human body touches any phase line of the output end, it will not cause any harm to the human body.

[0046] The smart ammeter SW determines the current size transmitted by the current transformer TA, and decides whether to output a control signal according to the threshold value preset by the smart ammeter SW. There are two types of control signals:

[0047] 1. The emergency stop signal output in case of short circuit is output through the 5th pin of the intelligent ammeter SW.

[0048] 2. The slow stop signal of overload output is output through pin 14 of the intelligent ammeter SW.

[0049] The emergency stop signal controls the second intermediate relay KA2. When pin 5 of the intelligent ammeter SW outputs the emergency stop signal, the coil of the second intermediate relay KA2 is energized, and the normally open contacts pin 6 and pin 4 of the second intermediate relay KA2 are attracted. Pin 6 of the second intermediate relay KA2 is energized, and the current is transmitted to the first end of the coil of the power relay K1. Pins 1 and 2 of the normally closed contacts of the power relay K1 are disconnected, and the main circuit is powered off. The delay of this process is very short to prevent the scope of the fault from expanding.

[0050] The slow stop signal controls the linked combination of the first time relay KT1, the second time relay KT2, and the first intermediate relay KA1. Once the slow stop signal is received, it starts to work. The working process is: the slow stop signal is transmitted from the 14th pin of the intelligent ammeter to the 14th pin of the first time relay KT1, the coil of relay KT1 is energized, and the timing starts. After the delay is set according to the delay, the normally open contacts 9 and 5 of the first time relay KT1 are energized, and the 5th pin is connected to the 12V power supply. Therefore, the 9th pin of the first time relay KT1 outputs a 12V voltage, and the 12V voltage is loaded to the 4th and 14th pins of the second time relay KT2: the 4th pin of the second time relay KT2 is energized, and the 4th and 12th pins of KT2 are in the normally closed state. After the 14th pin of the KT2 coil is energized, the timing starts. After the delay time is up, the 4th and 12th pins of KT2 will be disconnected. During the delay time, the 12V voltage reaches the first intermediate relay KA1 line through the 4th and 12th pins of KT2. Pin 8 at one end of the coil, the first intermediate relay KA1 is energized and actuated, pins 5 and 3 at both ends of the second normally open contact of the first intermediate relay KA1 are attracted, pin 3 of the first intermediate relay KA1 is connected to a 12V power supply, pin 5 of the first intermediate relay KA1 is energized, and the power is transmitted to the first end of the coil of the power relay K1 through a wire, the coil of the power relay K1 is energized and actuated, pins 1 and 3 of the normally closed contacts are disconnected, and the main circuit is cut off; when pin 9 of the normally open contact of the first time relay KT1 transmits 12V voltage to pin 14 of the second time relay KT2, the coil of the second time relay KT2 is energized, and the second time relay KT2 starts delay timing. When the delay time is up, pins 4 and 12 of the normally closed contacts of the second time relay KT2 are disconnected, then pin 8 at one end of the coil of the first intermediate relay KA1 is de-energized, and pins 3 and 5 at both ends of the normally closed contacts of the first intermediate relay KA1 are disconnected, thereby de-energizing the coil of the power relay K1 and resetting it, and the main circuit is restored.

[0051] The above process is delayed shutdown and delayed connection after shutdown.

[0052] The following is the process of delaying the power supply after the protection shuts off the power supply: after the 14th pin of the first end of the coil of the first time relay KT1 receives the slow stop signal, when the power-off protection starts after the delay of the first time relay KT1 ends, the 9th pin of the first time relay KT1 connects to the 5th pin, and sends the signal to the 14th pin of the second time relay KT2, and the second time relay KT2 starts to delay. The delay period of the second time relay KT2 is the time when the power relay K1 shuts off the main circuit output for protection and power off. When the delay time of the second time relay KT2 is up, the second time relay KT2 is actuated, so that the 12th pin and the 4th pin of the normally closed contact of the second time relay KT2 are disconnected, and the first intermediate relay KA1 loses power and resets, and the 5th pin of the first intermediate relay KA1 outputs a low level to reset the power relay K1, and the 1st and 3rd pins of the normally closed contacts of the power relay K1 are connected, and finally the main circuit is restored to the power supply state.

[0053] Working process of over-temperature alarm module: comparator U1 adopts LM358, resistors R2, R3, R8, and R9 form a voltage divider circuit to provide a reference voltage for comparator U1, P3 socket is connected to the thermistor, the thermistor and resistors R4, R6, and R7 form a temperature sampling circuit, when the sampled temperature value is converted into voltage and input into pin 2 of the comparator, it is compared with the reference voltage at pin 3. If the temperature exceeds the limit, comparator U1 outputs a low-level alarm signal from pin 1, transistor Q1 is turned on, buzzer BZ2 alarms, and at the same time, the high-level signal obtained by node NET1 is input to pin 14 of the coil of the first time relay KT1 of the intelligent control module, and the intelligent control module starts delay protection.

[0054] After the over-temperature alarm signal of the over-temperature alarm module of the present invention is transmitted to the intelligent protection module, the working process of the intelligent protection module is the same as when it receives the aforementioned slow stop signal, which will not be repeated here.

[0055] In order to prevent electrical sparks from causing fire, an arc extinguishing module is also installed, which can reduce the electrical sparks to a level that cannot cause fire.

[0056] The insulation resistance tester H2 monitors the insulation degree between the main circuit output and the casing (or input ground). If the insulation is lower than the standard value, an alarm will be sounded to remind you to pay attention to safety.

[0057] In summary, it can be seen that: the main circuit of this technical solution is energized, and the isolation transformer T1 isolates the mains power output. Due to the function of the isolation transformer T1, touching any line of the output terminal will not cause harm to the human body. The main switch is a high-power relay K1. The current transformer TA detects the size of the circuit current and generates a current sampling signal to send to the intelligent ammeter for processing. If the circuit current exceeds the safety requirements, the intelligent ammeter generates an output signal to the intelligent control module, and the intelligent control module controls the power relay K1 to operate and cut off the power. Ensure the safe use of electricity by users. Furthermore, the device can be equipped with an explosion-proof casing. Ensure the safe use of electricity by users, and will not cause combustion or explosion in flammable and explosive environments. The generated electrical sparks are enclosed in the explosion-proof box, and external flammable substances will not invade the box to damage electrical equipment.

[0058] The device adopts power isolation 1:1 transformer T1 and arc extinguishing circuit. It is characterized by double protection. It can effectively play different protective roles in the case of small current and overload large current, and the current limiting protection threshold is adjustable. In the case of small current or even leakage current, there will be no power failure and no electric shock hazard, which can ensure the normal operation of the load. When the ambient or body temperature rises to the warning temperature, it will alarm and automatically cut off the circuit to protect the safety of electricity use. When the circuit or load is overloaded, the protector cuts off the power supply to protect the line and load from damage and prevent fire. The values ​​of each stage of overcurrent can be adjusted according to the actual application environment. Ensure that the power supply is cut off before the danger occurs. The process generates arcs and takes a long time, which is easy to cause fire. Therefore, this device is equipped with an explosion-proof shell to play a flameproof role.

[0059] The present invention provides users with flexible and safe electrical equipment, and plays a good role in preventing electric shock, combustion and explosion, etc.

[0060] 1. The product is protected by an explosion-proof shell, with an isolation transformer as the core component of the power supply equipment, and is equipped with an intermediate relay, time relay, power relay, current sensor, intelligent ammeter, temperature sensor, alarm buzzer, and circuit breaker.

[0061] 2. Within the set temperature range and the set power range, the device can operate normally. When the set parameters are exceeded, the device will issue an early warning. When the working condition exceeds the limit, the power supply line will be cut off immediately to ensure safety.

[0062] The output end of the present invention is insulated from the earth. If a human body touches any end of the output, it will not cause an electric shock accident. It is safer than traditional power supply equipment. Since the device adopts an explosion-proof shell, it can be used in flammable and explosive environments without causing accidents, and the arc is minimized to prevent fire. This function can be achieved by connecting the device in series in a circuit.

[0063] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An electrical explosion-proof isolation protection device, characterized in that: It includes an input overcurrent protection switch, an isolation transformer, a current transformer, a power relay, an intelligent protection module, and an output overcurrent protection switch. The input end of the input overcurrent protection switch is used to connect to the mains. The output overcurrent protection switch is a mechanical mains / protection switching switch. The first input side of the output overcurrent protection switch is a two-phase mains pin, and the second input side of the output overcurrent protection switch is a two-phase protection circuit pin. The output side of the input overcurrent protection switch is divided into two paths: the first path: the two pins on the output side of the input overcurrent protection switch are connected one by one to the two-phase line pins of the first mains power line on the input side of the output overcurrent protection switch; Second path: the two pins on the output side of the input overcurrent protection switch are connected to the two pins on the primary side of the isolation transformer in a one-to-one correspondence, the first pin on the secondary side of the isolation transformer is connected to the input side terminal of the normally closed contact of the power relay, the current transformer is sleeved outside the electrical connection line between the first pin on the secondary side of the isolation transformer and the input side terminal of the normally closed contact of the power relay, the output side terminal of the normally closed contact of the power relay is connected to the first phase line terminal of the two pins of the second protection circuit on the input side of the output overcurrent protection switch, and the second phase line terminal of the two pins of the second protection circuit on the input side of the output overcurrent protection switch is connected to the second pin on the secondary side of the isolation transformer; The two ends of the current transformer are connected to the two input terminals of the intelligent protection module in a one-to-one correspondence; the control signal output end of the intelligent protection module is connected to the first end of the coil of the power relay, and the second end of the coil of the power relay is grounded; The intelligent protection module includes an intelligent ammeter, a first intermediate relay KA1, a second intermediate relay KA2, a first time relay KT1, and a second time relay KT2, and two signal input terminals of the intelligent ammeter are connected to the two ends of the current transformer in a one-to-one correspondence; The short-circuit signal output terminal of the intelligent ammeter is connected to the first end of the coil of the second intermediate relay KA2, the second end of the coil of the second intermediate relay KA2 is grounded, the second end of the normally open contact of the second intermediate relay KA2, pin 4, is connected to the 12V power supply, the first end of the normally open contact of the second intermediate relay KA2, pin 6, is connected to the first end of the coil of the power relay, and the second end of the coil of the power relay is grounded; The overload signal output end of the intelligent ammeter is connected to the first end of the coil of the first time relay, and the second end of the coil of the first time relay is grounded; the first end of the normally open contact of the first time relay is connected to the 12V power supply, and the second end of the normally open contact of the first time relay is divided into three paths: the first path is connected to the first end of the coil of the second time relay, and the second end of the coil of the second time relay is grounded; the second path is connected to the first end of the normally closed delay jump contact of the second time relay, and the second end of the normally closed delay jump contact of the second time relay is connected to the first end of the coil of the first intermediate relay, and the second end of the coil of the first intermediate relay is grounded; the third path is connected to the first end of the first normally open contact of the first intermediate relay, and the second end of the first normally open contact of the first intermediate relay is simultaneously connected to the 12V power supply and the second end of the normally open contact of the second intermediate relay, and the first end of the normally open contact of the second intermediate relay is connected to the first end of the coil of the power relay; A first end of the second normally open contact of the first intermediate relay is connected to a 12V power supply, a second end of the second normally open contact of the first intermediate relay is connected to a first end of the coil of the power relay; The electrical explosion-proof isolation protection device also includes an arc extinguishing circuit, which includes an arc extinguisher, and the arc extinguisher is connected in series to the first phase line on the output side of the output overcurrent protection switch.

2. The electrical explosion-proof isolation protection device according to claim 1, characterized in that: It also includes an alarm module, which includes an insulation resistance measuring instrument H2 and an alarm horn; The signal acquisition input end of the insulation resistance measuring instrument H2 includes two pins, and the two pins of the signal acquisition input end of the insulation resistance measuring instrument H2 are connected one by one with the two-phase pins of the second protection circuit on the input side of the output overcurrent protection switch; The two pins of the alarm signal output terminal of the insulation resistance measuring instrument H2 are connected to the two power supply input terminals of the alarm horn.

3. The electrical explosion-proof isolation protection device according to claim 1 or 2, characterized in that: It also includes an over-temperature protection device, which includes a comparator, a reference voltage circuit, a thermistor, a temperature signal circuit, and an over-temperature alarm circuit; The reference voltage circuit includes a second resistor, a third resistor, an eighth resistor, and a ninth resistor. The second resistor and the third resistor are connected in parallel to form a first parallel circuit. The eighth resistor and the ninth resistor are connected in parallel to form a second parallel circuit. The first end of the first parallel circuit is connected to a 12V power supply. The second end of the first parallel circuit is connected in series to the first end of the second parallel circuit. The second end of the second parallel circuit is grounded. The middle point of the first parallel circuit and the second parallel circuit is connected to the reference voltage input end of the comparator. The temperature signal circuit includes a fourth resistor, a sixth resistor, and a seventh resistor. The sixth and seventh resistors are connected in parallel to form a third parallel circuit. The first end of the thermistor is connected to a 12V power supply, the second end of the thermistor is connected to a first end of a fourth resistor R4, the second end of the fourth resistor R4 is connected to a first end of the third parallel circuit, and the second end of the third parallel circuit is grounded. The middle point between the fourth resistor R4 and the first end of the third parallel circuit is connected to the temperature signal input end of the comparator. The over-temperature alarm circuit includes a fifth resistor, a first resistor, a first transistor, an over-temperature alarm buzzer, and a first diode. The first transistor is a PNP transistor. The first resistor is connected between the emitter and the base of the first transistor. The emitter of the first transistor is connected to a 12V power supply. The base of the first transistor is connected in series with the fifth resistor and then connected to the alarm signal output end of the comparator. The collector of the first transistor is connected to the first end of the over-temperature alarm buzzer, and the second end of the over-temperature alarm buzzer is grounded; the positive electrode of the first diode is connected to the second end of the over-temperature alarm buzzer, and the negative electrode of the first diode is connected to the first end of the over-temperature alarm buzzer; the collector of the first transistor is also connected to the over-temperature signal input end of the intelligent protection module, and the over-temperature signal input end is the first end of the coil of the first time relay.

4. The electrical explosion-proof isolation protection device as claimed in claim 3, characterized in that: The comparator model is LM358.

5. The electrical explosion-proof isolation protection device as claimed in claim 3, characterized in that: It also includes a heat dissipation circuit, which includes a heat dissipation fan and a first switch. The first end of the first switch is connected to a 12V power supply, the second end of the first switch is connected to a first terminal of the heat dissipation fan, and the second terminal of the heat dissipation fan is grounded; the wind direction of the heat dissipation fan is set toward the isolation transformer.

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