CN2572692Y - Power frequency test centralized warning instrument - Google Patents
Power frequency test centralized warning instrument Download PDFInfo
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- CN2572692Y CN2572692Y CN 02283979 CN02283979U CN2572692Y CN 2572692 Y CN2572692 Y CN 2572692Y CN 02283979 CN02283979 CN 02283979 CN 02283979 U CN02283979 U CN 02283979U CN 2572692 Y CN2572692 Y CN 2572692Y
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Abstract
The utility model relates to power frequency invasion warning equipment used for controlling a main distributing frame of a public telephone network, which is composed of an electric sensor, a band pass filtering amplifier, an analog-digital converter A/D, and a single chip computer MSU, wherein, the electric sensor is a voltage sensor or a current sensor and is arranged on a tested main cable; the output end of the electric sensor is connected with the input end of the band pass filtering amplifier; the output end of the band pass filtering amplifier is connected with the input end of the analog-digital converter A/D; the output end of the A/D is connected with the input end and the output end of the single chip computer MCU; the output of the MCU is connected with a signal input interface of a concentrated signal processor positioned on the main distributing frame; the clock signal output end of the MCU is connected with the clock signal control input end of the analog-digital converter A/D. The utility model can simultaneously carry out the judgment of the electric current and the voltage, carries out quantification to the quantity of the voltage and the electric current, and exactly judges whether dangerous power frequency electricity is added on a user line according to software. The utility model basically does not have a wrong warning phenomenon or a non-warning phenomenon, and enhances reliability and accuracy.
Description
Technical field
The utility model relates to a kind of main frame power frequency intrusion alarm equipment that is used to control public telephone network.
Background technology
At present; the subscriber's line of public telephone network often has forceful electric power; such as handing over system 220V; wait voltage to invade with high-voltage line touching induction; this forceful electric power gently then makes the Security Unit action; heavy then cause switch to damage, for fear of the generation of this situation with find this type of fault early, need the alarm device of detection power frequencies (50HZ).The intrusion form of expression of this type of forceful electric power is two kinds, a kind of is the form of electric current, a kind of is the form of voltage, when the circuit that is linked into machine room be ceases to be busy to the time, can't produce electric current, show as voltage form, when the circuit that inserts machine room has inserted Security Unit, may show as voltage form, this moment, Security Unit did not move, also may show as current forms, this moment, the discharge tube of Security Unit was breakdown, and traditional detection mode is not considered this situation comprehensively, or is by the current detecting mode, judged by voltage system, therefore cause the possibility of erroneous judgement very big.
Summary of the invention
The purpose of this utility model is exactly in order to address the above problem, and a kind of high power frequency detection set warning instrument of accuracy of alarming is provided.
Technical solution of the present utility model:
A kind of power frequency detection set warning instrument, it is characterized in that it is by electric transducer, band-pass filter amplifier, modulus converter A/D and single-chip microprocessor MCU are formed, electric transducer is voltage or current sensor, it is arranged on the tested main cable, the input of the output tape splicing pass filter amplifier of electric transducer, the output of band-pass filter amplifier connects the input of modulus converter A/D, the output of A/D connects the input/output terminal of single-chip microprocessor MCU, the output of MCU links to each other with the signal input interface of concentrated signal processor on being positioned at main frame by interface circuit, and the clock signal output terminal of MCU connects the clock signal control input end of modulus converter A/D.
The utility model can carry out the judgement of electric current and voltage simultaneously, and the voltage and current amount is quantized, and judges whether correctly that according to software adventurous power frequency electricity is added on the subscriber's line.The utility model can all focus on the power frequency alarm signal of each row on all main frames on the central apparatus, and does not alarm phenomenon basically by mistake and do not alarm phenomenon, and reliability and accuracy improve greatly.
Description of drawings
Fig. 1 is a theory diagram of the present utility model.
Fig. 2 is a kind of concrete electric theory diagram of the present utility model.
Fig. 3 is an electrical schematic diagram of the present utility model.
Embodiment
As Fig. 1, power frequency detection set warning instrument of the present utility model is by electric transducer, band-pass filter amplifier, modulus converter A/D and single-chip microprocessor MCU are formed, electric transducer is voltage or current sensor, it is arranged on the tested main cable, the input of the output tape splicing pass filter amplifier of electric transducer, the output of band-pass filter amplifier connects the input of modulus converter A/D, the output of A/D connects the input/output terminal of single-chip microprocessor MCU, the output of MCU links to each other with the signal input interface (model is RS-485) of concentrated signal processor on being positioned at main frame by interface circuit (model can be RS-485), and the clock signal output terminal of MCU connects the clock signal control input end of modulus converter A/D.
Electric transducer of the present utility model can be a voltage sensor, also current sensor, and they can be provided with separately as required, also can mix setting.
Voltage sensor can be made of (flat cable is active computer transfer of data winding displacement and is cut into one section one section formation) two flat cables, and they are clamped in tested main cable in appearance, promptly constitute voltage sensor.Current sensor can be made of the coil of band shape magnetic core, and it is sleeved on tested main cable periphery and promptly constitutes current sensor.
As Fig. 2, electric transducer of the present utility model preferably adopts current sensor arranged side by side and voltage sensor, they are separately positioned on the tested main cable, their output connects the input of variable connector (model can be 4051) respectively by shaping amplification circuit separately, the input of the output tape splicing pass filter amplifying circuit of variable connector, the output of bandpass filtering amplifying circuit connects the input of modulus converter A/D by rectification circuit (being used for waveform transformation), the output of A/D connects the input/output terminal of single-chip microprocessor MCU, the output one tunnel of MCU connects the control end of variable connector, another road connects the signal input interface of concentrating signal processor by interface circuit, the photoisolator of leading up in addition also connects the signal input interface of concentrating signal processor, the alarm output signal FS of Security Unit connects the input of single-chip microprocessor MCU on the distributing frame by photoisolator, the input/output terminal of MCU also is connected to electric erasable memory (model can be AT24C01) and address toggle switch, and the clock signal output terminal of MCU connects the clock signal control input end of modulus converter A/D.
The power frequency detection set warning instrument of surveying on the main cable with a velamen is an example, as Fig. 3, on this main cable, be provided with a voltage sensor J0 and a current sensor J1, the output of voltage sensor J0 connects the voltage shaping amplifier, this voltage shaping amplifier can be by amplifier U6A, U6B, U6C, resistance R 2, R32, R33, R34, R35, bidirectional diode D6, capacitor C 2, C12 constitutes, its input is drawn the output that meets voltage sensor J0 from the in-phase input end of U6A and U6B, and its output is drawn by second level amplifier U6D from the output of U6C and met variable connector U7.Wherein, C2, C12, R2, D6 form signal conditioning circuit, filtering high-frequency interferencing signal and spike; R32, R33, R34, R35, amplifier U6A, U6B, U6C constitute differential amplifier circuit, and faint voltage induced signal is amplified, and suppress common mode disturbances.Resistance R 40, R41, R42, potentiometer VD2, amplifier U6D form reverse ratio circuit, can suitably amplify signal by regulating VD2.
The output of current sensor J1 connects the current shaping amplifier, this current shaping amplifier can be by amplifier U1D, resistance R 1, R24, R25, R26, R16, potentiometer VD1, capacitor C 1, C1 1, C5, bidirectional diode D5 constitutes, and its input is drawn from the inverting input of U1D, connect the output of current sensor J1 by resistance R 24, its output is drawn from the output of U1D and is met variable connector U7.Wherein, C1, C11, R1, D5 form signal conditioning circuit, filtering high-frequency interferencing signal and spike; R24, R26, VD1 and amplifier U1D constitute reverse ratio amplifying circuit, can suitably amplify signal by regulating VD1; C5, R16 resistance-capacitance circuit have every straight effect, can suppress the interstage voltage drift of amplifying circuit.
It is the CD4051 integrated circuit that variable connector U7 can adopt model, its input X0, X1 links to each other with the output of current shaping amplifier and the output of voltage shaping amplifier respectively, its output is drawn tape splicing pass filter amplifier from its X pin, and its control end is drawn from its A, B, C pin and connect single-chip microprocessor MCU.Variable connector U7 is used for the power-frequency voltage signal and the power current signal of voltage shaping amplifier and two passages of current shaping amplifier are switched.
Band-pass filter amplifier is by amplifier U1A, resistance R 3-R7, R20, capacitor C 3, C4, C6 constitute, its input is drawn capacitor C 4 and the resistance R 3 output X pin that meets variable connector U7 by serial connection from the in-phase input end of U1A, and its output is drawn by rectification circuit from the output of U1A and connect modulus converter A/D.Wherein, R3, R4, R5, R6, R7, R20, C3, C4, U1A form the second order bandwidth-limited circuit, and its centre frequency is 50HZ.
Rectification circuit can be by amplifier U1B, U1C, resistance R 8-R13, diode D1-D4 constitutes, the output that its input is drawn tape splicing pass filter amplifier from the in-phase input end of the inverting input of U1B and U1 C is the output of amplifier U1A, and its output is drawn from the output of U1B and U1C and connect A/D converter after merging by forward diode D3 and D2 respectively.Above-mentioned rectification circuit is a precise rectification circuit, and signal is carried out waveform transformation.
It is the TLC549 integrated circuit that modulus converter A/D (U5) can adopt model, and it is 8 bits serial A/D conversion chip, and its inside contains sampling hold circuit, and the input of modulus converter A/D is drawn the output that connects rectification circuit from its AIN pin, and its output connects single-chip microprocessor MCU.
It is the AT89C52 integrated circuit that single-chip microprocessor MCU (U2) can adopt model, the input/output terminal P11 of MCU, P12 links to each other with sheet choosing end CS with the data output end D0 of A/D converter U5 respectively, the clock signal output terminal of MCU is drawn the clock signal control input end CLK that meets U5 from its P10 pin, the input/output terminal P15 of MCU, P16, P17 meets the control end A of variable connector U7, B, C, the serial input/output terminal RXD of MCU, TXD meets 485 interface circuit U4, it is the MAX487 integrated circuit that this 485 interface circuit U4 can adopt model, its input/output terminal is drawn RXD and the TXD end that meets MCU from its R pin and D pin respectively, and the output of U4 is from its A, the B pin draw be positioned at main frame on the signal input interface of concentrated signal processor link to each other.Interface circuit U4, resistance R 29, R30, R31 form 485 communicating circuits, and the MAX487 chip can articulate 127 contacts, and R31 is the terminal build-out resistor.
Input/output terminal T0, the T1 of MCU links to each other with the input of photoelectrical coupler OP1, OP2 respectively, and the output of OP1, OP2 connects the signal input interface of concentrated signal processor respectively by amplifying triode N1, N2 separately.Wherein, photoelectrical coupler OP1, OP2, resistance R 14, R15, R21, R22, R27, R28, R37, R38, triode N1, N2 form two-way alarm output circuit, OP1, OP2 make photoelectricity and isolate, R14, R15, R27, R28 are pull-up resistor, and R21, R22, R37, R38 are current-limiting resistance, and N1, N2 are used for increasing driving force.Input/output terminal P20, the P21 of MCU, P22 meet electric erasable memory U8 (model can be AT24C01), are used to store data.The input/output terminal P00-P07 ground connection location toggle switch U3 of MCU, toggle switch U3 and exclusion R19 constitute the address setting circuit.The input INTO of MCU connects the output of photoelectrical coupler OP3, and the alarm output of respective column Security Unit links to each other on the input of OP3 and the main frame.Wherein, photoelectrical coupler OP3 and resistance R 18, R36 form FS alarm signal sample circuit, and OP3 plays the photoelectricity buffer action, and R18 draws effect on being, R36 is a metering function.
The electrification reset that the external capacitor C 7 of single-chip microprocessor MCU, resistance R 23 realize Single Chip Microcomputer (SCM) system, crystal oscillator Y1, capacitor C 9, C10 are connected between the PIN20 (X2) and PIN21 (X1) of single-chip microprocessor MCU, and what system was provided is clock.Single-chip microprocessor MCU (U2) mainly realizes following function:
(1), control A/D chip (U5) is realized data acquisition and computing:
U2 realizes the A/D conversion, and the data of gathering is carried out computing by P10 (PIN2), P11 (PIN3), P12 pins such as (PIN4) and control U5, judges whether it reaches alarm status.
And carry out reading and writing data between the chip U8 (AT24C01) (2):
Carry out serial communication by P20 (SDA), P21 (SCL), P22 pins such as (SDA) and U8,, realize setting, the change of parameter with the various parameters of storage and reading system.
(3) carry out exchanges data with chip U4 (MAX487) and realize communication function:
Carry out exchanges data by PIN11 (RXD), PIN13 (TXD), PIN5 (P13) and U4, realize with set of signals in the data communication of processor, and carry out address setting by R19, U3, realize the multi computer communication function.
In addition, in the utility model, capacitor C S1, CS2, CS3, CS4, resistance R 43, light-emitting diode D7 is power filter and power indicating circuit.
The course of work of the present utility model is, obtaining current signal by current sensor J1 is also amplified, again by the in addition filtering of 50HZ band pass filter, enter A/D conversion becoming digital quantity, be sent in the single-chip microprocessor MCU, equally, voltage signal is obtained signal by voltage sensor J0, amplify the back by 50HZ filtering, A/D converts digital quantity to and sends in the single-chip microprocessor MCU, and single-chip microprocessor MCU is carried out digital processing, after the judgement, by the RS485 bus, the power frequency intrusion signal that whether has of each column unit is delivered to a concentrator, concentrator is delivered to central control board by PSTN or various transmission paths such as DDN or TCP/IP.
In the utility model, the signal of current sensor output carries out signal condition by resistance-capacitance circuit earlier, and behind the simulation multicircuit switch, carry out filtering and amplify, be the 50HZ signal because system will detect, therefore the filter circuit that adopts is the second order bandpass filtering.Signal through filtering amplify the back be less than+/-AC signal of 5V, the A/D converter of system's employing is a single supply, so signal is transformed to the signal of 0-5V behind precision rectifying, receives the input of A/D converter.Because the signal of voltage sensor output is the space radiation signal of power-frequency voltage, its intensity a little less than, before signal filtering is amplified, carry out differential amplification earlier.The simulation multicircuit switch is used for selecting voltage sensor passage and current sensor passage.Single-chip microprocessor MCU is sampled to analog signals, becomes digital signal by A/D converter, through after the computing, judges.System contains one 485 interface, and signal is delivered to concentrator, and simultaneity factor also can be done alarm signal output by the double switch amount.For improving the correctness of judging, system introduces the row alarm signal (FS actuating signal) of main cable simultaneously and does collaborative the analysis.
Software systems of the present utility model are gathered, after the computing, are done alarm and judge the signal of the signal of current sensor, voltage sensor.All less than alarming limit and not having the FS actuating signal, show then that current state is a normal condition as voltage, current signal, no power frequency invasion; Greater than the alarm limit, the FS actuating signal also appears in this moment as current signal, then shows current have strong power frequency invasion, alarm immediately; There is not the FS actuating signal as current signal greater than the alarm limit, then may be that power current adds up, very little for each to its power frequency component of subscribers feeder, for preventing it is interference signal, system's filtering of delaying time, if after time-delay a period of time, current signal is still greater than the alarm limit, then send out alarm signal, do the time-delay of different time according to varying in size of detected signal; Equally, if limit greater than alarm for voltage signal, the filtering interference signals of then also delaying time, delay time is to still then sending out alarm signal greater than the alarm limit.
Claims (5)
1, a kind of power frequency detection set warning instrument, it is characterized in that it is by electric transducer, band-pass filter amplifier, modulus converter A/D and single-chip microprocessor MCU are formed, electric transducer is voltage or current sensor, it is arranged on the tested main cable, the input of the output tape splicing pass filter amplifier of electric transducer, the output of band-pass filter amplifier connects the input of modulus converter A/D, the output of A/D connects the input/output terminal of single-chip microprocessor MCU, the output of MCU links to each other with the signal input interface of concentrated signal processor on being positioned at main frame by interface circuit, and the clock signal output terminal of MCU connects the clock signal control input end of modulus converter A/D.
2, by the described power frequency detection set of claim 1 warning instrument, it is characterized in that electric transducer or voltage sensor, or current sensor, they or be provided with separately, or mix and be provided with.
3, by the described power frequency detection set of claim 1 warning instrument, it is characterized in that described voltage sensor is made of two flat cables, they are clamped in tested main cable in appearance; Current sensor is made of the coil of band shape magnetic core, and it is sleeved on tested main cable periphery.
4, by the described power frequency detection set of claim 1 warning instrument, it is characterized in that current sensor arranged side by side and voltage sensor are separately positioned on the tested main cable, their output connects the input of variable connector respectively by shaping amplification circuit separately, the input of the output tape splicing pass filter amplifying circuit of variable connector, the output of bandpass filtering amplifying circuit connects the input of modulus converter A/D by rectification circuit, the output of A/D connects the input/output terminal of single-chip microprocessor MCU, the output one tunnel of MCU connects the control end of variable connector, another road connects the signal input interface of concentrating signal processor by interface circuit, the photoisolator of leading up in addition also connects the signal input interface of concentrating signal processor, the alarm output signal FS of Security Unit connects the input of single-chip microprocessor MCU on the distributing frame by photoisolator, the input/output terminal of MCU also is connected to electric erasable memory and address toggle switch, and the clock signal output terminal of MCU connects the clock signal control input end of modulus converter A/D.
5, by the described power frequency detection set of claim 1 warning instrument, it is characterized in that on this main cable, being provided with a voltage sensor J0 and a current sensor J1, the output of voltage sensor J0 connects the voltage shaping amplifier, this voltage shaping amplifier can be by amplifier U6A, U6B, U6C, resistance R 2, R32, R33, R34, R35, bidirectional diode D6, capacitor C 2, C12 constitutes, its input is drawn the output that meets voltage sensor J0 from the in-phase input end of U6A and U6B, and its output is drawn by second level amplifier U6D from the output of U6C and met variable connector U7; The output of current sensor J1 connects the current shaping amplifier, this current shaping amplifier can be by amplifier U1D, resistance R 1, R24, R25, R26, R16, potentiometer VD1, capacitor C 1, C11, C5, bidirectional diode D5 constitutes, and its input is drawn from the inverting input of U1D, connect the output of current sensor J1 by resistance R 24, its output is drawn from the output of U1D and is met variable connector U7; Input X0, the X1 of variable connector U7 links to each other with the output of current shaping amplifier and the output of voltage shaping amplifier respectively, and its output is drawn tape splicing pass filter amplifier from its X pin, and its control end is drawn from its A, B, C pin and connect single-chip microprocessor MCU; Band-pass filter amplifier is by amplifier U1A, resistance R 3-R7, R20, capacitor C 3, C4, C6 constitute, its input is drawn capacitor C 4 and the resistance R 3 output X pin that meets variable connector U7 by serial connection from the in-phase input end of U1A, and its output is drawn by rectification circuit from the output of U1A and connect modulus converter A/D; Rectification circuit is by amplifier U1B, U1C, resistance R 8-R13, diode D1 D4 constitutes, the output that its input is drawn tape splicing pass filter amplifier from the in-phase input end of the inverting input of U1B and U1C is the output of amplifier U1A, and its output is drawn from the output of U1B and U1C and connect A/D converter after merging by forward diode D3 and D2 respectively; The input of modulus converter A/D is drawn the output that connects rectification circuit from its AIN pin, and its output connects single-chip microprocessor MCU; Input/output terminal P11, the P12 of single-chip microprocessor MCU links to each other with sheet choosing end CS with the data output end D0 of A/D converter respectively, the clock signal output terminal of MCU is drawn the clock signal control input end CLK that meets U5 from its P10 pin, input/output terminal P15, the P16 of MCU, P17 meet control end A, B, the C of variable connector U7, serial input/output terminal RXD, the TXD of MCU connects input/output terminal R pin and the D pin of 485 interface circuit U4 respectively, the output of U4 from its A, B pin draw be positioned at main frame on the signal input interface of concentrated signal processor link to each other; Input/output terminal T0, the T1 of MCU links to each other with the input of photoelectrical coupler OP1, OP2 respectively, and the output of OP1, OP2 connects the signal input interface of concentrated signal processor respectively by amplifying triode N1, N2 separately; Input/output terminal P20, the P21 of MCU, P22 meet electric erasable memory U8; The input/output terminal P00-P07 ground connection location toggle switch U3 of MCU; The input INTO of MCU connects the output of photoelectrical coupler OP3, and the alarm output of respective column Security Unit links to each other on the input of OP3 and the main frame.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02283979 CN2572692Y (en) | 2002-01-29 | 2002-11-01 | Power frequency test centralized warning instrument |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN02203714 | 2002-01-29 | ||
| CN022037144 | 2002-01-29 | ||
| CN 02283979 CN2572692Y (en) | 2002-01-29 | 2002-11-01 | Power frequency test centralized warning instrument |
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| Publication Number | Publication Date |
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| CN2572692Y true CN2572692Y (en) | 2003-09-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 02283979 Expired - Fee Related CN2572692Y (en) | 2002-01-29 | 2002-11-01 | Power frequency test centralized warning instrument |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101988960B (en) * | 2009-08-07 | 2013-03-06 | 铨盛电子股份有限公司 | Digital electric meter capable of dynamically compensating and correcting reading |
| CN103458322A (en) * | 2013-09-09 | 2013-12-18 | 苏州新天远节能环保科技有限公司 | Detection device and detection method for main distribution frame power frequency electric intrusion |
| CN104101775A (en) * | 2013-04-02 | 2014-10-15 | 优利德科技(中国)有限公司 | Current measuring circuit |
| CN112787606A (en) * | 2020-12-30 | 2021-05-11 | 西安建筑科技大学 | Signal reading circuit |
| CN115411953A (en) * | 2022-10-31 | 2022-11-29 | 深圳市暗能量电源有限公司 | Intelligent household direct-current power supply system |
-
2002
- 2002-11-01 CN CN 02283979 patent/CN2572692Y/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101988960B (en) * | 2009-08-07 | 2013-03-06 | 铨盛电子股份有限公司 | Digital electric meter capable of dynamically compensating and correcting reading |
| CN104101775A (en) * | 2013-04-02 | 2014-10-15 | 优利德科技(中国)有限公司 | Current measuring circuit |
| CN103458322A (en) * | 2013-09-09 | 2013-12-18 | 苏州新天远节能环保科技有限公司 | Detection device and detection method for main distribution frame power frequency electric intrusion |
| CN103458322B (en) * | 2013-09-09 | 2016-09-28 | 苏州新天远节能环保科技有限公司 | A kind of main frame power frequency electric invasion detecting device and detection method |
| CN112787606A (en) * | 2020-12-30 | 2021-05-11 | 西安建筑科技大学 | Signal reading circuit |
| CN115411953A (en) * | 2022-10-31 | 2022-11-29 | 深圳市暗能量电源有限公司 | Intelligent household direct-current power supply system |
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| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |