CN206532401U - A kind of residual current detection circuit of detector for electric fire protection - Google Patents
A kind of residual current detection circuit of detector for electric fire protection Download PDFInfo
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- CN206532401U CN206532401U CN201720169561.3U CN201720169561U CN206532401U CN 206532401 U CN206532401 U CN 206532401U CN 201720169561 U CN201720169561 U CN 201720169561U CN 206532401 U CN206532401 U CN 206532401U
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Abstract
The utility model is related to a kind of residual current detection circuit of detector for electric fire protection.Including：Residual current transformer, signal acquisition and failure detector circuit, operational amplification circuit, reference voltage circuit, filter circuit, wherein, signal acquisition is connected residual current transformer with failure detector circuit, the input of the output end concatenation operation amplifying circuit of signal acquisition and failure detector circuit, the input of the output end concatenation operation amplifying circuit of reference voltage circuit, the output end of operational amplification circuit connects the input of filter circuit.By implementing the utility model, the residual current signal in electric fire monitoring system can be normally detected, signal during wiring faults can be also detected, and fault-signal short circuit and open circuit that can be different to two kinds make a distinction, and facilitate the failture evacuation at user scene.
Description
Technical field
The utility model is related to the electrical fire monitoring field of low-voltage power supply system, more specifically to a kind of electric
The residual current detection circuit of fire monitoring detector.
Background technology
Electric fire monitoring system is mounted in low-voltage distribution system, relevant in low-voltage distribution work system for monitoring
Electrical fire produces the electric parameter (such as residual current, temperature signal) of hidden danger, and gathers prison by monitoring host computer equipment
Data are surveyed as centralized Control and centralized management, when being detected parameter more than alarm setting value in protected circuit, can be sent
Alarm signal, control signal, and the system that can indicate that alarm position.
Standardization Administration of China has promulgated the national standard of newest electric fire monitoring system within 2015
It is distinctly claimed in GB 14287-2014, wherein residual current type detector for electric fire protection part GB14287.2-2014：Adopt
With the detector of external residual current sensor, the connecting line between the connected residual current sensor of signal processing unit breaks
When road or short circuit, detector should be able to send sound, light fault-signal in 100s.
Since standard promulgation, the manufacturer of each electric fire monitoring system is proposed the electric fire of various model specifications
Calamity monitoring detector product, employs the detection method of a variety of residual currents.But, the detection circuit of current main flow is not
Short circuit and the break signal of residual current formula transformer input can be effectively distinguished simultaneously, short circuit or break signal can only be recognized
For same failure fault-signal, it has not been convenient to live failture evacuation, therefore application slightly has deficiency.
Utility model content
The technical problems to be solved in the utility model is, can not be for the above-mentioned existing detection circuit of prior art simultaneously
Short circuit and the break signal of residual current formula transformer input are effectively distinguished, short circuit or break signal can only be identified as same
Plant failure fault-signal, it has not been convenient to which there is provided a kind of residue electricity of detector for electric fire protection for the defect of live failture evacuation
Current detection circuit.
The utility model solves the technical scheme that its technical problem used：Construct a kind of detector for electric fire protection
Residual current detection circuit, including：Residual current transformer, signal acquisition and failure detector circuit, operational amplification circuit, ginseng
Potential circuit, filter circuit are examined, wherein,
The signal acquisition is connected the residual current transformer with failure detector circuit, and the signal acquisition is examined with failure
The output end of slowdown monitoring circuit connects the input of the operational amplification circuit, and the output end of the reference voltage circuit connects the fortune
The input of amplifying circuit is calculated, the output end of the operational amplification circuit connects the input of the filter circuit；
The residual current transformer is used to gather residual current signal, and the signal acquisition is received with failure detector circuit
And detect the residual current signal, and transmit after the residual current signal after processing is amplified by operational amplification circuit
To the filter circuit, the reference voltage circuit is used to provide reference voltage for the operational amplification circuit.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, in addition to：With
In handling the output signal of the filter circuit and send the control circuit of control signal, the output end of the filter circuit
The input of the connection control circuit.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, the signal
Collection includes with failure detector circuit：Resistance R2, resistance R5, electric capacity C2, diode D1, diode D2, wherein,
The resistance R5, diode D2, electric capacity C2 are connected in parallel, the resistance R5, diode D2, the electric capacity being connected in parallel
The output end of the C2 connections residual current transformer, the resistance R5 being connected in parallel, diode D2, electric capacity C2 one end pass through institute
State resistance R2 connections diode D1 negative pole, the positive pole connection analog power of the diode D1.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, two pole
Pipe D2 is Transient Suppression Diode.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, the computing
Amplifying circuit includes：Resistance R1, resistance R3, electric capacity C1, electric capacity C4, operational amplifier U1A, wherein,
The inverting input of the operational amplifier U1A passes through the resistance R3 connections signal acquisition and fault detect
The output end of circuit, the inverting input of the operational amplifier U1A passes through electric capacity C1 and resistance the R1 connection in parallel Suo Shu
Operational amplifier U1A output end；
The in-phase input end of the operational amplifier U1A connects the signal acquisition and the output end of failure detector circuit,
The in-phase input end of the operational amplifier U1A connects the output end of the reference voltage circuit, the operational amplifier U1A's
In-phase input end is grounded by the electric capacity C4.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, the filtering
Circuit includes：Resistance R4, electric capacity C3, wherein,
The output end of the operational amplification circuit passes through the output end of the resistance R4 connections filter circuit, the fortune
The output end for calculating amplifying circuit is grounded by the resistance R4 and electric capacity C3 that connects.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, the reference
Potential circuit includes：Resistance R8, resistance R9, electric capacity C7, electric capacity C8, electric capacity C9, electric capacity C10, electric capacity E1, electric capacity E2, diode
D3, voltage reference chip U2, Dolby circuit, wherein,
The pin 1 of the voltage reference chip U2 connects digital power, the voltage reference core by the Dolby circuit
The piece U2 connection analog power of pin 1, the pin 1 of the voltage reference chip U2 passes through the electric capacity E1 in parallel, electric capacity C7, electricity
Hold C8 and diode D3 connections voltage reference chip U2 pin 3；
The connection power supply VREF of pin 2 of the voltage reference chip U2, the pin 2 of the voltage reference chip U2 passes through institute
State the output end of the resistance R8 connections reference voltage circuit；
The pin 2 of the voltage reference chip U2 passes through the electric capacity E2 in parallel and the electric capacity C9 connections voltage reference core
Piece U2 pin 3, the pin 2 of the voltage reference chip U2 connects one end of the resistance R8, the other end of the resistance R8
Pass through the resistance R9 in parallel and electric capacity C10 connections voltage reference chip U2 pin 3；
The pin 3 of the voltage reference chip U2 is grounded.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, two pole
Pipe D3 is Transient Suppression Diode.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, the noise reduction
Circuit is magnetic bead, one end connection analog power of the magnetic bead, the other end connection digital power of the magnetic bead.
Preferably, the residual current detection circuit of detector for electric fire protection described in the utility model, the electric capacity
E1 and electric capacity E2 is tantalum electric capacity.
Implement a kind of residual current detection circuit of detector for electric fire protection of the present utility model, with following beneficial
Effect：The residual current detection circuit, including：Residual current transformer, signal acquisition and failure detector circuit, operation amplifier electricity
Road, reference voltage circuit, filter circuit, wherein, signal acquisition is connected residual current transformer with failure detector circuit, and signal is adopted
The input of collection and the output end concatenation operation amplifying circuit of failure detector circuit, the output end concatenation operation of reference voltage circuit
The input of amplifying circuit, the output end of operational amplification circuit connects the input of filter circuit.By implementing the utility model,
The residual current signal in electric fire monitoring system can be normally detected, signal during wiring faults can be also detected, and
Fault-signal short circuit and open circuit that can be different to two kinds make a distinction, and facilitate the failture evacuation at user scene, solve existing skill
Short circuit and the defect of break signal of residual current formula transformer input can not be effectively distinguished present in art.
Brief description of the drawings
Below in conjunction with drawings and Examples, the utility model is described in further detail, in accompanying drawing：
Fig. 1 is a kind of structural representation of the residual current detection circuit of detector for electric fire protection of the utility model；
Fig. 2 be a kind of detector for electric fire protection of the utility model residual current detection circuit in signal acquisition with therefore
The circuit diagram of barrier detection circuit, operational amplification circuit and filter circuit；
Fig. 3 be a kind of detector for electric fire protection of the utility model residual current detection circuit in reference voltage circuit
Circuit diagram.
Embodiment
In order to be more clearly understood to technical characteristic of the present utility model, purpose and effect, accompanying drawing is now compareed detailed
Illustrate this embodiment of the present utility model.
Fig. 1 is a kind of structural representation of the residual current detection circuit of detector for electric fire protection of the utility model.
Specifically, the residual current detection circuit of the detector for electric fire protection is supervised for residual-current electrical fire
Control in detector body, including：Residual current transformer, signal acquisition and failure detector circuit 100, operational amplification circuit 200,
Reference voltage circuit 300, filter circuit 400, control circuit 500, wherein,
Signal acquisition is connected residual current transformer, signal acquisition and failure detector circuit 100 with failure detector circuit 100
Output end concatenation operation amplifying circuit 200 input, the output end concatenation operation amplifying circuit of reference voltage circuit 300
200 input, the output end of operational amplification circuit 200 connects the input of filter circuit 400, the output of filter circuit 400
End connects the input of connection control circuit 500.
Residual current transformer is used to gather residual current signal, and signal acquisition is received and examined with failure detector circuit 100
Residual current signal is surveyed, and is transmitted to filtered electrical after the residual current signal after processing is amplified by operational amplification circuit 200
Road 400, reference voltage circuit 300 is used to provide reference voltage for operational amplification circuit 200.
Control circuit 500 is used to handle the output signal of filter circuit 400 and sends control signal, and control circuit is
A kind of microprocessor with information processing and controlling function.
Fig. 2 be a kind of detector for electric fire protection of the utility model residual current detection circuit in signal acquisition with therefore
The circuit diagram of barrier detection circuit, operational amplification circuit and filter circuit.
Specifically, signal acquisition includes with failure detector circuit 100：Resistance R2, resistance R5, electric capacity C2, diode D1, two
Pole pipe D2, wherein, resistance R5, diode D2, electric capacity C2 are connected in parallel, and resistance R5, diode D2, the electric capacity C2 being connected in parallel connect
The output end of residual current transformer is connect, the resistance R5 that is connected in parallel, diode D2, electric capacity C2 one end are connected by resistance R2
Diode D1 negative pole, diode D1 positive pole connection analog power, it is preferable that analog power AVCC is 3.3V；Residual current
The parameter of transformer is 1A/0.5mA.
Preferably, diode D2 is Transient Suppression Diode.Output terminal shortcircuit when residual current transformer, open circuit or just
Often during work, the DC voltage at resistance R5 two ends is different, by the processing of operational amplification circuit 200, filter circuit 400, micro- place
Reason circuit, which can be recognized, judges that current residual current detection is normally to detect, be in short circuit or off state.
With reference to Fig. 2, operational amplification circuit 200 includes：Resistance R1, resistance R3, electric capacity C1, electric capacity C4, operational amplifier
U1A, wherein,
Operational amplifier U1A inverting input is defeated by resistance R3 connection signal acquisitions and failure detector circuit 100
Go out end, the output that operational amplifier U1A inverting input passes through shunt capacitance C1 and resistance R1 concatenation operation amplifiers U1A
End；The multiplication factor of operational amplification circuit is determined by resistance R1 and resistance R3.
Operational amplifier U1A in-phase input end connection signal acquisition and the output end of failure detector circuit 100, computing is put
Big device U1A in-phase input end connects the output end of reference voltage circuit 300, and operational amplifier U1A in-phase input end passes through
Electric capacity C4 is grounded.Preferably, the output voltage REF of the output end of reference voltage circuit 300 is 1.25V；Operational amplifier U1A's
Supply voltage AVCC is 3.3V.
With reference to Fig. 2, filter circuit 400 includes：Resistance R4, electric capacity C3, wherein, the output end of operational amplification circuit 200 is led to
The output end of resistance R4 connections filter circuit 400 is crossed, the output end of operational amplification circuit 200 passes through series resistance R4 and electric capacity C3
Ground connection.
Fig. 3 be a kind of detector for electric fire protection of the utility model residual current detection circuit in reference voltage circuit
Circuit diagram.
Specifically, reference voltage circuit 300 includes：Resistance R8, resistance R9, electric capacity C7, electric capacity C8, electric capacity C9, electric capacity
C10, electric capacity E1, electric capacity E2, diode D3, voltage reference chip U2, Dolby circuit, wherein,
Voltage reference chip U2 pin 1 connects digital power by Dolby circuit, and voltage reference chip U2 pin 1 connects
Connect analog power, it is preferable that digital power VCC is 3.3V, analog power AVCC is 3.3V.Voltage reference chip U2 pin 1
Pass through shunt capacitance E1, electric capacity C7, electric capacity C8 and diode D3 connection voltage reference chips U2 pin 3.
The voltage reference chip U2 connection power supply VREF of pin 2, voltage reference chip U2 pin 2 is connected by resistance R8
The output end of reference voltage circuit 300；Preferably, power supply VREF is 2.5V；The output electricity of the output end of reference voltage circuit 300
Press as 1.25V.
Voltage reference chip U2 pin 2 by shunt capacitance E2 and electric capacity C9 connection voltage reference chips U2 pin 3,
The voltage reference chip U2 connection resistance of pin 2 R8 one end, the resistance R8 other end is connected by parallel resistance R9 and electric capacity C10
Connect voltage reference chip U2 pin 3.
Voltage reference chip U2 pin 3 is grounded.
Preferably, diode D3 is Transient Suppression Diode.
Preferably, Dolby circuit is magnetic bead, one end connection analog power of magnetic bead, the other end connection numeral electricity of magnetic bead
Source.
Preferably, electric capacity E1 and electric capacity E2 is tantalum electric capacity.
By implementing the utility model, the residual current signal in electric fire monitoring system can be normally detected,
Signal during wiring faults can be detected, and fault-signal short circuit and open circuit that can be different to two kinds make a distinction, and facilitate user
The failture evacuation at scene, the short circuit of residual current formula transformer input can not effectively be distinguished by solving present in prior art
With the defect of break signal.
Above example is only to illustrate technical concepts and features of the present utility model, and its object is to allow be familiar with technique
Personage can understand content of the present utility model and implement accordingly, protection domain of the present utility model can not be limited.It is all with
The equivalent changes and modifications that the utility model right is done, all should belong to the utility model claim covers model
Enclose.
Claims (10)
1. a kind of residual current detection circuit of detector for electric fire protection, it is characterised in that including：Residual current mutual inductance
Device, signal acquisition and failure detector circuit (100), operational amplification circuit (200), reference voltage circuit (300), filter circuit
(400), wherein,
The signal acquisition is connected the residual current transformer, the signal acquisition and failure with failure detector circuit (100)
Detect that the output end of circuit (100) connects the input of the operational amplification circuit (200), the reference voltage circuit (300)
Output end connect the input of the operational amplification circuit (200), the output end connection institute of the operational amplification circuit (200)
State the input of filter circuit (400)；
The residual current transformer is used to gather residual current signal, and the signal acquisition connects with failure detector circuit (100)
Receive and detect the residual current signal, and the residual current signal after processing is put by operational amplification circuit (200)
Transmitted after big to the filter circuit (400), the reference voltage circuit (300) is used to be the operational amplification circuit (200)
Reference voltage is provided.
2. the residual current detection circuit of detector for electric fire protection according to claim 1, it is characterised in that also wrap
Include：For the output signal for handling the filter circuit (400) and the control circuit (500) for sending control signal, the filter
The input of the output end connection control circuit (500) of wave circuit (400).
3. the residual current detection circuit of detector for electric fire protection according to claim 1 or 2, it is characterised in that
The signal acquisition includes with failure detector circuit (100)：Resistance R2, resistance R5, electric capacity C2, diode D1, diode D2, its
In,
The resistance R5, diode D2, electric capacity C2 are connected in parallel, and the resistance R5, diode D2, the electric capacity C2 being connected in parallel connect
The output end of the residual current transformer is connect, the resistance R5 that is connected in parallel, diode D2, electric capacity C2 one end pass through the electricity
Hinder R2 connections diode D1 negative pole, the positive pole connection analog power of the diode D1.
4. the residual current detection circuit of detector for electric fire protection according to claim 3, it is characterised in that described
Diode D2 is Transient Suppression Diode.
5. the residual current detection circuit of detector for electric fire protection according to claim 1 or 2, it is characterised in that
The operational amplification circuit (200) includes：Resistance R1, resistance R3, electric capacity C1, electric capacity C4, operational amplifier U1A, wherein,
The inverting input of the operational amplifier U1A passes through the resistance R3 connections signal acquisition and failure detector circuit
(100) output end, the inverting input of the operational amplifier U1A passes through electric capacity C1 and resistance the R1 connection in parallel Suo Shu
Operational amplifier U1A output end；
The in-phase input end of the operational amplifier U1A connects the signal acquisition and the output end of failure detector circuit (100),
The in-phase input end of the operational amplifier U1A connects the output end of the reference voltage circuit (300), the operational amplifier
U1A in-phase input end is grounded by the electric capacity C4.
6. the residual current detection circuit of detector for electric fire protection according to claim 1 or 2, it is characterised in that
The filter circuit (400) includes：Resistance R4, electric capacity C3, wherein,
The output end of the operational amplification circuit (200) by the output end of the resistance R4 connections filter circuit (400),
The output end of the operational amplification circuit (200) is grounded by the resistance R4 and electric capacity C3 that connects.
7. the residual current detection circuit of detector for electric fire protection according to claim 1 or 2, it is characterised in that
The reference voltage circuit (300) includes：Resistance R8, resistance R9, electric capacity C7, electric capacity C8, electric capacity C9, electric capacity C10, electric capacity E1,
Electric capacity E2, diode D3, voltage reference chip U2, Dolby circuit, wherein,
The pin 1 of the voltage reference chip U2 connects digital power, the voltage reference chip U2 by the Dolby circuit
The connection analog power of pin 1, the pin 1 of the voltage reference chip U2 passes through the electric capacity E1 in parallel, electric capacity C7, electric capacity C8
And diode D3 connections voltage reference chip U2 pin 3；
The connection power supply VREF of pin 2 of the voltage reference chip U2, the pin 2 of the voltage reference chip U2 passes through the electricity
Hinder the output end of the R8 connections reference voltage circuit (300)；
The pin 2 of the voltage reference chip U2 passes through the electric capacity E2 in parallel and the electric capacity C9 connections voltage reference chip U2
Pin 3, the pin 2 of the voltage reference chip U2 connects one end of the resistance R8, and the other end of the resistance R8 passes through
The resistance R9 and electric capacity C10 connections voltage reference chip U2 in parallel pin 3；
The pin 3 of the voltage reference chip U2 is grounded.
8. the residual current detection circuit of detector for electric fire protection according to claim 7, it is characterised in that described
Diode D3 is Transient Suppression Diode.
9. the residual current detection circuit of detector for electric fire protection according to claim 7, it is characterised in that described
Dolby circuit is magnetic bead, one end connection analog power of the magnetic bead, the other end connection digital power of the magnetic bead.
10. the residual current detection circuit of detector for electric fire protection according to claim 7, it is characterised in that institute
Electric capacity E1 and electric capacity E2 is stated for tantalum electric capacity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720169561.3U CN206532401U (en) | 2017-02-23 | 2017-02-23 | A kind of residual current detection circuit of detector for electric fire protection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720169561.3U CN206532401U (en) | 2017-02-23 | 2017-02-23 | A kind of residual current detection circuit of detector for electric fire protection |
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| CN206532401U true CN206532401U (en) | 2017-09-29 |
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| CN201720169561.3U Active CN206532401U (en) | 2017-02-23 | 2017-02-23 | A kind of residual current detection circuit of detector for electric fire protection |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109149508A (en) * | 2018-05-25 | 2019-01-04 | 江苏凯隆电器有限公司 | A kind of circuit breaker internal redundancy protection architecture and its guard method |
| CN110794332A (en) * | 2019-11-14 | 2020-02-14 | 浙江晨泰科技股份有限公司 | Residual current transformer detection system for fire detection detector and detection method thereof |
| CN111815880A (en) * | 2020-08-07 | 2020-10-23 | 成都惠之慧安全科技有限公司 | Electric fire and gas intelligent monitoring alarm system |
| CN112180148A (en) * | 2019-07-05 | 2021-01-05 | 上海赋锦信息技术有限公司 | Electric appliance fire detection system and detection method |
| CN116054826A (en) * | 2023-03-31 | 2023-05-02 | 中勍科技股份有限公司 | Digital low-cost high-precision current frequency conversion system |
-
2017
- 2017-02-23 CN CN201720169561.3U patent/CN206532401U/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109149508A (en) * | 2018-05-25 | 2019-01-04 | 江苏凯隆电器有限公司 | A kind of circuit breaker internal redundancy protection architecture and its guard method |
| CN109149508B (en) * | 2018-05-25 | 2024-03-12 | 江苏凯隆电器有限公司 | Circuit breaker internal redundancy protection structure and protection method thereof |
| CN112180148A (en) * | 2019-07-05 | 2021-01-05 | 上海赋锦信息技术有限公司 | Electric appliance fire detection system and detection method |
| CN110794332A (en) * | 2019-11-14 | 2020-02-14 | 浙江晨泰科技股份有限公司 | Residual current transformer detection system for fire detection detector and detection method thereof |
| CN111815880A (en) * | 2020-08-07 | 2020-10-23 | 成都惠之慧安全科技有限公司 | Electric fire and gas intelligent monitoring alarm system |
| CN116054826A (en) * | 2023-03-31 | 2023-05-02 | 中勍科技股份有限公司 | Digital low-cost high-precision current frequency conversion system |
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