CN213091853U - Electric fire and gas intelligent monitoring alarm device - Google Patents
Electric fire and gas intelligent monitoring alarm device Download PDFInfo
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- CN213091853U CN213091853U CN202021636746.9U CN202021636746U CN213091853U CN 213091853 U CN213091853 U CN 213091853U CN 202021636746 U CN202021636746 U CN 202021636746U CN 213091853 U CN213091853 U CN 213091853U
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Abstract
The utility model provides an intelligent monitoring and alarming device for electrical fire and gas, which comprises a signal processing unit, a CT fault detection control output circuit and a residual current transformer; the method comprises the steps that a hysteresis comparator in a CT fault detection control output circuit is used for collecting and processing line voltage between a residual current transformer and an A end of a signal collection channel, and a processed level signal is input into a signal processor to judge whether a line has a fault or not; the utility model discloses the circuit has the function whether the connecting wire between real-time online automated inspection signal processing unit and the external residual current transformer takes place to open circuit or short circuit fault, the assurance of bigger degree people's electrical apparatus safe in utilization, just the utility model discloses a circuit is simple, and the cost is lower, and the stable performance is reliable.
Description
Technical Field
The utility model relates to a fire control safety field, concretely relates to electric fire and gas intelligent monitoring alarm device.
Background
In part 2 of the national standard GB 14287.2-2014 electrical fire monitoring system: the residual current type electrical fire monitoring detector is defined as being composed of a residual current sensor and a signal processing unit. The residual current sensor is a sensor for measuring the change of the residual current value in a protected line, and is generally a residual current transformer. The current common technical scheme of the fire detector for the electric appliance is that a residual current transformer is connected with a signal processing unit through an external connecting wire to form the fire detector. Compared with GB 14287.2-2005, GB 14287.2-2014 newly increases the technical requirements: when a connecting line between the signal processing unit and the external residual current transformer is broken or short-circuited, the residual current type electric fire monitoring detector can detect a line fault.
SUMMERY OF THE UTILITY MODEL
Promotion to above-mentioned fire safety field national standard, the utility model provides an electrical apparatus transships and intelligent monitoring alarm device to reach national standard's requirement.
In order to achieve the purpose of the utility model, the utility model adopts the technical scheme that:
the intelligent monitoring and alarming device for the electrical fire and the gas comprises a signal processing unit, a CT fault detection control output circuit and a residual current transformer; the CT fault detection control output circuit comprises a resistor R95, a constant current source module, a first hysteresis comparator, a second hysteresis comparator, a first photoelectric isolation circuit and a second photoelectric isolation circuit;
a signal acquisition channel end A and a signal acquisition channel B of the signal processing unit are respectively connected with an external residual current transformer through connecting wires, the voltage value of the acquisition channel end A is input to one end of a resistor R95, a constant current source module is connected with a resistor R95 in series, the voltage formed at the other end of the resistor R95 is Vb, the voltage difference at the two ends of the resistor R95 is input into a first hysteresis comparator as comparison voltage, a reference voltage is generated inside the first hysteresis comparator, the reference voltage and the comparison voltage are compared and amplified, a first level signal is output at an output end and input into a first photoelectric isolation circuit, the first photoelectric isolation circuit is used for carrying out electric isolation processing on the first level signal by a front-stage circuit and a rear-stage circuit, the anti-interference capability of the rear-stage circuit is enhanced, the first level signal after the isolation processing is input into the signal processing unit, and the signal processing unit judges whether the first level signal transmitted by the first photoelectric isolation circuit is high or low, judging whether the connection between the residual current transformer and the end A of the signal acquisition channel fails or not;
the voltage difference between two ends of the resistor R95 is used as a comparison voltage to be input into a second hysteresis comparator, a reference voltage is generated inside the second hysteresis comparator, the reference voltage and the comparison voltage are compared and amplified, a second level signal is output at an output end and input into a second photoelectric isolation circuit, the second photoelectric isolation circuit is used for carrying out electric isolation processing on the second level signal by a front-stage circuit and a rear-stage circuit, the anti-interference capability of the rear-stage circuit is enhanced, the second level signal after the isolation processing is input into a signal processing unit, and the signal processing unit judges whether the connection between the residual current transformer and the A end of the signal acquisition channel fails or not by judging the high or low of the second level signal transmitted by the second photoelectric isolation circuit.
According to the invention, the CT fault detection control output circuit is arranged to acquire the voltage value of the channel end A and process the voltage value to obtain a level signal, and the level signal is input into the signal processing unit, and the signal processing unit judges the received level signal, so that whether a fault exists when the signal processing unit is connected with the external residual current transformer is determined.
Further, the constant current source module comprises a resistor Rb4, a resistor Rb3, a diode DB1, a diode DB2, a diode DB3, a diode DB4, and a transistor Q2, wherein one end of the resistor Rb4 is connected to a power supply, the other end of the resistor Rb4 is connected to an emitter of a transistor Q2, a collector of the transistor Q2 is connected to an anode of the diode DB4, and a cathode of the diode DB4 is connected to a resistor R95; the anode of the diode DB3 is connected with a power supply, the cathode of the diode DB3 is connected with the anode of the diode DB2, the cathode of the diode DB2 is connected with the anode of the diode DB1, the cathode of the diode DB1 is connected with one end of the resistor Rb3, the other end of the resistor Rb3 is grounded, and the cathode of the diode DB1 is also connected with the base of the triode Q2; the current magnitude in the constant current source module is controlled by increasing or decreasing the number of diodes.
Further, in the present invention, the first hysteresis comparator includes a dual operational amplifier circuit U12A, a resistor Rb1, a variable resistor Rb2, and a resistor Rb 20; one end of a resistor Rb1 is connected with a power supply, the other end of the resistor Rb1 is connected with a variable resistor Rb2, the other end of the variable resistor Rb2 is grounded, the other end of the resistor Rb1 is connected with the reverse input end of the double operational amplifier, the voltage input to the reverse input end is larger than the voltage input to the same-direction input end of the double operational amplifier U12A when the residual current transformer is normally connected with the A end of the signal acquisition channel by adjusting the variable resistor Rb2, the same-direction input end of the double operational amplifier U12A is connected with one end of a resistor R95, and the output end of the double operational amplifier U12A is connected with the same-phase input end of the double operational amplifier U12A after being connected with a resistor Rb; when the connection of the residual current transformer and the end A of the signal acquisition channel has an open circuit fault, the output of the first hysteresis comparator is a high level signal.
Further, in the present invention, the first hysteresis comparator includes a dual operational amplifier circuit U12B, a resistor Rb6, a variable resistor Rb7, and a resistor Rb 21; one end of a resistor Rb6 is connected with a power supply, the other end of the resistor Rb6 is connected with a variable resistor Rb7, the other end of the variable resistor Rb7 is grounded, the other end of the resistor Rb6 is connected with the reverse input end of a double operational amplifier, the voltage input to the reverse input end is smaller than the voltage input to the non-inverting input end of the double operational amplifier U12B when the residual current transformer is normally connected with the A end of a signal acquisition channel by adjusting the variable resistor Rb7, the non-inverting input end of the double operational amplifier U12B is connected with one end of a resistor R95, and the output end of the double operational amplifier U12B is connected with the non-inverting input end of the double operational amplifier U12B after being connected with a; when the residual current transformer is connected with the end A of the signal acquisition channel and a short-circuit fault occurs, the output of the second hysteresis comparator is a low-level signal.
Further, first photoelectric isolation circuit includes resistance Rb10, opto-coupler chip U13 and resistance Rb11, and pin 1 of opto-coupler chip U13 links to each other with the output of first hysteresis comparator through resistance Rb10, and pin 2 ground connection of opto-coupler chip U13, and pin 3 of opto-coupler chip U13 is grounded after establishing ties with resistance Rb11, and pin 3 of opto-coupler chip U13 is output pin, to signal processing unit output high level signal, and pin 4 connection power of opto-coupler chip U13; the first photoelectric isolation circuit utilizes the isolation characteristic of the optocoupler chip U13 to block high voltage and protect the signal processor.
Further, the second photoelectric isolation circuit includes resistance Rb8, opto-coupler chip U14 and resistance Rb9, pin 1 of opto-coupler chip U14 links to each other with the output of the hysteresis comparator of second through resistance Rb8, pin 2 ground of opto-coupler chip U14, pin 3 of opto-coupler chip U14 and resistance Rb9 ground connection after establishing ties, pin 3 of opto-coupler chip U14 is output pin, high level signal is exported to the signal processing unit, pin 4 connection power of opto-coupler chip U14; the second photoelectric isolation circuit utilizes the isolation characteristic of the optocoupler chip U14 to block high voltage and protect the signal processor.
Further, the utility model discloses a CT fault detection control output circuit supply voltage source is 5V voltage source.
Furthermore, the model of the diode DB1, the diode DB2, the diode DB3, and the diode DB4 of the CT fault detection control output circuit of the present invention is 1N 4148.
Further, the utility model discloses a CT fault detection control output circuit opto-coupler chip U13 and opto-coupler chip U14's model is TLP 127.
The utility model has the advantages that: the utility model discloses the circuit has the function whether the connecting wire between real-time online automated inspection signal processing unit and the external residual current transformer takes place to open circuit or short circuit fault, the assurance of bigger degree people's electrical apparatus safe in utilization, just the utility model discloses a circuit is simple, and the cost is lower, and the stable performance is reliable.
Drawings
FIG. 1 is a schematic diagram of a CT fault detection control circuit;
fig. 2 is a schematic diagram of an intelligent monitoring and alarming device for electrical fire and gas.
Detailed Description
To make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the following examples and drawings, and the exemplary embodiments and descriptions thereof of the present invention are only used for explaining the present invention, and are not intended as limitations of the present invention.
Example 1
The embodiment provides an electric fire and gas intelligent monitoring alarm device.
The intelligent monitoring and alarming device for electrical fire and gas of the embodiment shown in fig. 1-2 comprises a signal processing unit, a CT fault detection control output circuit and a residual current transformer; the CT fault detection control output circuit comprises a constant current source module, a hysteresis comparator 1, a hysteresis comparator 2, a photoelectric isolation circuit 1 and a photoelectric isolation circuit 2;
the signal acquisition channel end A and the signal acquisition channel B of the signal processing unit are respectively connected with an external residual current transformer through connecting wires, and one end of a resistor R95 in the CT fault detection control output circuit is connected with the connecting wire between the signal acquisition channel end A of the signal processing unit and the external residual current transformer;
in the CT fault detection control output circuit, the other end of a resistor R95 is connected with a constant current source module, in the constant current source module, a power supply is connected with one end of a resistor Rb4 and the anode of a diode DB3, the other end of the resistor Rb4 is connected with the emitter of a triode Q2, the collector of the triode Q2 is connected with the anode of a diode DB4, and the cathode of the diode DB4 is connected with a resistor R95; diode DB3, diode DB2 and diode DB1 are connected in series, the negative pole of diode DB1 is connected with one end of resistor Rb3, the other end of resistor Rb3 is grounded, and the negative pole of diode DB1 is also connected with the base of triode Q2. The constant current source module outputs a constant current to generate a voltage Vb at the other end of the resistor R95.
The voltage at two ends of the resistor Rb 95 is used as comparison voltage and input into a first hysteresis comparator, in the first hysteresis comparator, a power supply is connected with one end of a resistor Rb1, the other end of the resistor Rb1 is connected with a variable resistor Rb2, the other end of the variable resistor Rb2 is grounded, the other end of the resistor Rb1 is connected with a reverse input end pin 2 of a double-operational amplifier, the voltage input into the reverse input end is slightly larger than the voltage when the residual current transformer is normally connected with the end A of a signal acquisition channel by adjusting the variable resistor Rb2, the non-inverting input end of the double-operational amplifier is connected with one end of a resistor R95, and the output end of the double-operational amplifier is connected with a resistor Rb20 in series and then connected with the non-inverting; when the connection of the residual current transformer and the end A of the signal acquisition channel has an open circuit fault, the output of the first hysteresis comparator is a high level signal. The output end of the first hysteresis comparator is connected with a first photoelectric isolation circuit, the first photoelectric isolation circuit comprises a resistor Rb10, an optical coupling chip U13 and a resistor Rb11, one end of the resistor Rb10 is connected with the output end of the first hysteresis comparator, the other end of the resistor Rb10 is connected with a pin 1 of an optical coupling chip U13, a pin 2 of an optical coupling chip U13 is grounded, a pin 3 of the optical coupling chip U13 is grounded after being connected with the resistor Rb11 in series, a pin 3 of the optical coupling chip U13 is connected with an input pin of a signal processing unit, a pin 4 of the optical coupling chip U13 is connected with a power supply, the first photoelectric isolation circuit carries out electric isolation processing on a first level signal in a front-stage circuit and a rear-stage circuit, the anti-jamming capability of the rear-stage circuit is enhanced, the first level signal after isolation processing is input to the signal processing unit, if the signal processing unit detects that the first level signal transmitted by the first photoelectric isolation circuit is a high, judging that the connection between the residual current transformer and the end A of the signal acquisition channel has an open circuit fault;
the voltage at two ends of R95 is input into a second hysteresis comparator as a comparison voltage, a power supply in the second hysteresis comparator is connected with one end of a resistor Rb6, the other end of the resistor Rb6 is connected with a variable resistor Rb7, the other end of the variable resistor Rb7 is grounded, the other end of the resistor Rb6 is connected with the reverse input end of a double operational amplifier, the voltage input into the reverse input end is slightly smaller than the voltage when the residual current transformer is normally connected with the A end of a signal acquisition channel by adjusting the variable resistor Rb7, the non-inverting input end of the double operational amplifier is connected with one end of the resistor R95, and the output end of the double operational amplifier is connected with the non-inverting input end of the double operational amplifier after being connected with the resistor Rb21 in; when the residual current transformer is connected with the end A of the signal acquisition channel and has a short-circuit fault, the output of the second hysteresis comparator is a low-level signal; the output end of the second hysteresis comparator is connected with a second photoelectric isolation circuit, the second photoelectric isolation circuit comprises a resistor Rb8, an optical coupling chip U14 and a resistor Rb9, one end of the resistor Rb8 is connected with the output end of the second hysteresis comparator, the other end of the resistor Rb8 is connected with a pin 1 of an optical coupling chip U14, a pin 2 of an optical coupling chip U14 is grounded, a pin 3 of the optical coupling chip U14 is grounded after being connected with the resistor Rb9 in series, a pin 3 of an optical coupling chip U14 is connected with an input pin of an input quantity of a signal processing unit, and a pin 4 of the optical coupling chip U14 is connected with a power supply; the second photoelectric isolation circuit carries out electrical isolation processing on the second level signal by the front-stage circuit and the rear-stage circuit, the anti-interference capability of the rear-stage circuit is enhanced, the second level signal after isolation processing is input into the signal processing unit, and if the signal processing unit detects that the second level signal transmitted by the second photoelectric isolation circuit is a low level signal, the short-circuit fault of the connection between the residual current transformer and the A end of the signal acquisition channel is judged.
Claims (9)
1. An electric fire and gas intelligent monitoring alarm device is characterized by comprising a signal processing unit, a CT fault detection control output circuit and a residual current transformer; the CT fault detection control output circuit comprises a resistor R95, a constant current source module, a first hysteresis comparator, a second hysteresis comparator, a first photoelectric isolation circuit and a second photoelectric isolation circuit;
a signal acquisition channel end A and a signal acquisition channel B of the signal processing unit are respectively connected with an external residual current transformer through connecting wires, the voltage value of the acquisition channel end A is input to one end of a resistor R95, a constant current source module is connected with a resistor R95 in series, the voltage formed at the other end of the resistor R95 is Vb, the voltage difference at the two ends of the resistor R95 is input into a first hysteresis comparator as comparison voltage, a reference voltage is generated inside the first hysteresis comparator, the reference voltage and the comparison voltage are compared and amplified, a first level signal is output at an output end and input into a first photoelectric isolation circuit, the first photoelectric isolation circuit is used for carrying out electric isolation processing on the first level signal by a front-stage circuit and a rear-stage circuit, the anti-interference capability of the rear-stage circuit is enhanced, the first level signal after the isolation processing is input into the signal processing unit, and the signal processing unit judges whether the first level signal transmitted by the first photoelectric isolation circuit is high or low, judging whether the connection between the residual current transformer and the end A of the signal acquisition channel fails or not;
the voltage difference between two ends of the resistor R95 is used as a comparison voltage to be input into a second hysteresis comparator, a reference voltage is generated inside the second hysteresis comparator, the reference voltage and the comparison voltage are compared and amplified, a second level signal is output at an output end and input into a second photoelectric isolation circuit, the second photoelectric isolation circuit is used for carrying out electric isolation processing on the second level signal by a front-stage circuit and a rear-stage circuit, the anti-interference capability of the rear-stage circuit is enhanced, the second level signal after the isolation processing is input into a signal processing unit, and the signal processing unit judges whether the connection between the residual current transformer and the A end of the signal acquisition channel fails or not by judging the high or low of the second level signal transmitted by the second photoelectric isolation circuit.
2. An intelligent monitoring and alarm device for electric fire and gas as claimed in claim 1, wherein said constant current source module comprises a resistor Rb4, a resistor Rb3, a diode DB1, a diode DB2, a diode DB3, a diode DB4, and a transistor Q2, one end of the resistor Rb4 is connected to the power supply, the other end of the resistor Rb4 is connected to the emitter of a transistor Q2, the collector of the transistor Q2 is connected to the anode of the diode DB4, and the cathode of the diode DB4 is connected to the resistor R95; the anode of the diode DB3 is connected with a power supply, the cathode of the diode DB3 is connected with the anode of the diode DB2, the cathode of the diode DB2 is connected with the anode of the diode DB1, the cathode of the diode DB1 is connected with one end of the resistor Rb3, the other end of the resistor Rb3 is grounded, and the cathode of the diode DB1 is also connected with the base of the transistor Q2.
3. The intelligent monitoring and alarming device for electrical fire and gas as claimed in claim 1, wherein the first hysteresis comparator comprises a dual operational amplifier circuit U12A, a resistor Rb1, a variable resistor Rb2 and a resistor Rb 20; one end of a resistor Rb1 is connected with a power supply, the other end of the resistor Rb1 is connected with a variable resistor Rb2, the other end of the variable resistor Rb2 is grounded, the other end of the resistor Rb1 is connected with the reverse input end of the double operational amplifier, the voltage input to the reverse input end is larger than the voltage input to the same-direction input end of the double operational amplifier U12A when the residual current transformer is normally connected with the A end of the signal acquisition channel by adjusting the variable resistor Rb2, the same-direction input end of the double operational amplifier U12A is connected with one end of a resistor R95, and the output end of the double operational amplifier U12A is connected with the same-phase input end of the double operational amplifier U12A after being connected with a resistor Rb; when the connection of the residual current transformer and the end A of the signal acquisition channel has an open circuit fault, the output of the first hysteresis comparator is a high level signal.
4. The intelligent monitoring and alarming device for electrical fire and gas as claimed in claim 1, wherein the first hysteresis comparator comprises a dual operational amplifier circuit U12B, a resistor Rb6, a variable resistor Rb7 and a resistor Rb 21; one end of a resistor Rb6 is connected with a power supply, the other end of the resistor Rb6 is connected with a variable resistor Rb7, the other end of the variable resistor Rb7 is grounded, the other end of the resistor Rb6 is connected with the reverse input end of a double operational amplifier, the voltage input to the reverse input end is smaller than the voltage input to the non-inverting input end of the double operational amplifier U12B when the residual current transformer is normally connected with the A end of a signal acquisition channel by adjusting the variable resistor Rb7, the non-inverting input end of the double operational amplifier U12B is connected with one end of a resistor R95, and the output end of the double operational amplifier U12B is connected with the non-inverting input end of the double operational amplifier U12B after being connected with a; when the residual current transformer is connected with the end A of the signal acquisition channel and a short-circuit fault occurs, the output of the second hysteresis comparator is a low-level signal.
5. An electric fire and gas intelligent monitoring alarm device according to claim 1, wherein the first photoelectric isolation circuit comprises a resistor Rb10, an optical coupling chip U13 and a resistor Rb11, a pin 1 of the optical coupling chip U13 is connected with the output end of the first hysteresis comparator through a resistor Rb10, a pin 2 of the optical coupling chip U13 is grounded, a pin 3 of the optical coupling chip U13 is grounded after being connected in series with the resistor Rb11, a pin 3 of the optical coupling chip U13 is an output pin and outputs a high-level signal to the signal processing unit, and a pin 4 of the optical coupling chip U13 is connected with a power supply.
6. An intelligent monitoring and alarm device for an electrical fire and gas as claimed in claim 1, wherein the second photoelectric isolation circuit comprises a resistor Rb8, an optocoupler chip U14 and a resistor Rb9, a pin 1 of the optocoupler chip U14 is connected with the output end of the second hysteresis comparator through a resistor Rb8, a pin 2 of the optocoupler chip U14 is grounded, a pin 3 of the optocoupler chip U14 is connected with the resistor Rb9 in series and then grounded, a pin 3 of the optocoupler chip U14 is an output pin and outputs a high level signal to the signal processing unit, and a pin 4 of the optocoupler chip U14 is connected with a power supply.
7. The intelligent monitoring and alarming device for electric fire and gas as claimed in claim 1, further comprising a power supply voltage source, wherein the power supply voltage source is a 5V voltage source.
8. An intelligent monitoring and alarm device for electric fire and gas as claimed in claim 2, wherein the model numbers of said diodes DB1, DB2, DB3 and DB4 are 1N 4148.
9. The intelligent monitoring and alarming device for electrical fire and gas as recited in any one of claims 5 to 6, wherein the type of the optocoupler chip U13 and optocoupler chip U14 is TLP 127.
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| CN202021636746.9U CN213091853U (en) | 2020-08-07 | 2020-08-07 | Electric fire and gas intelligent monitoring alarm device |
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| CN202021636746.9U CN213091853U (en) | 2020-08-07 | 2020-08-07 | Electric fire and gas intelligent monitoring alarm device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117368798A (en) * | 2023-12-04 | 2024-01-09 | 浙江国利信安科技有限公司 | Fault detection circuit and related circuitry |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117368798A (en) * | 2023-12-04 | 2024-01-09 | 浙江国利信安科技有限公司 | Fault detection circuit and related circuitry |
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