CN2594802Y - Digital capacitance meter with wide measurement range - Google Patents
Digital capacitance meter with wide measurement range Download PDFInfo
- Publication number
- CN2594802Y CN2594802Y CN 02286887 CN02286887U CN2594802Y CN 2594802 Y CN2594802 Y CN 2594802Y CN 02286887 CN02286887 CN 02286887 CN 02286887 U CN02286887 U CN 02286887U CN 2594802 Y CN2594802 Y CN 2594802Y
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- circuit
- microprocessor
- cable
- control circuit
- processing unit
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- Expired - Fee Related
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Abstract
The utility model relates to a cable detector, which comprises a main machine, a secondary machine and a common conducting body which is connected with the main machine and the secondary machine, wherein, the main machine is composed of a microprocessor A, a speech signal processing unit A, A control circuit A, and an AD converter; the secondary machine is composed of a microprocessor B, a speech signal processing unit B, and a control circuit B; a cable connecting port A of the main machine is connected with a cable connecting port B of the secondary machine to form a detecting system of a computer terminal. The signal transmission of the utility model uses a direct current signal form and a double audio signal form. The utility model has stronger anti-interference ability, and can be suitable for the laying and the maintenance of ship cables and long-distance cables. The utility model is provided with a carrying power, and thus the utility model is convenient for being used for field operations.
Description
Technical field
The utility model relates to a kind of detecting instrument of electric wire, the instrument that detects especially for the cable core connection state.
Background technology
At electric power, in communication and the post and telecommunications engineering a large amount of cable layings is arranged, construction period cable wiring and the butt joint pith that is Engineering Quality Control, the instrument that detects is many with the artificial spot check of multimeter at present, this line inspection to polycore cable is that intensity is big, dull, repeat, very easily produce tired work, inefficiency, under-enumeration is more serious, be difficult to guarantee line inspection quality, whether only look into the cable two ends as the artificial line inspection is communicated with or opens a way, whether connect correctly and declare the Lu Yigen cable, it is far from being enough only looking into these two, because between heart yearn and heart yearn whether short circuit also be very crucial, and the workload that will judge between heart yearn whether short circuit is to look into to be communicated with or several times even tens times of open-circuit working amount.CN2415367Y proposes a kind of line diagnosis, the line inspection, connecting tester, and it improves line, line inspection work efficiency, can in time find multi-thread, few line, wrong line, guarantees the circuit correctness, and is beneficial to guaranteeing project progress and quality.But still there are many weak points, for example shipbuilding and maintenance, because the steel plate structure of hull, isolation or shielding action to light, sound, radio signal, dispose simple secondary machine and have only luminous, sounding, intercom function, powerless to isolation or shielding obstacle, also can't exclude the interference signal, reduced the reliability and the work efficiency that detect.Be cable in addition when straight line more than tens meters is laid, just become a radio receiving antenna, can accept various undesired signals.Detection signal adopts simple simulating signal or digital signal all to cause communication failures easily or produces error code, and test result reliability and efficient are reduced.Therefore, just become the key of current raising cable tester reliability and work efficiency for the configuration of the setting of detection signal and secondary machine structure.
Summary of the invention
The purpose of this utility model is at all difficulties of present detection polycore cable and the defective of existing detecting instrument, design a kind of instrument of connection, open circuit or short circuit of quick, accurate detection streamer heart yearn, no matter in various interference environments or under the isolation environment, can both guarantee reliability and detection efficiency.
The design proposal that the utility model adopted is: cable tester, it comprises main frame and slave, and the common conductor that connects them, it is characterized in that main frame is made up of microprocessor A, voice signal processing unit A, control circuit A and AD converter, microprocessor A and voice signal processing unit A and control circuit A form series loop; Input termination computer interface and the keyboard of microprocessor A, AD converter are connected between control circuit A output terminal and the microprocessor A; Slave is made up of microprocessor B, voice signal processing unit B and control circuit B, and microprocessor B and voice signal processing unit B and control circuit B form series loop, and display screen B is connected to the output terminal of microprocessor; The cable connectivity port A of main frame links to each other with the cable connectivity port B of slave and forms the computer terminal detection system.
Every heart yearn in the tested cable is connected on the cable connectivity port of main frame and slave, numbering is arranged on the port, the screen layer of cable or common conductor (as shell, the earth) are connected to the public port of main frame and slave, core number by keyboard input cable on main frame.Main frame adds dc level signal on every heart yearn, slave monitors whether DC level is arranged on each heart yearn, if DC level is arranged, according to the numbering of this heart yearn on slave cable connectivity port, numbering is modulated into double-audio signal by the double audio coding device returns to main frame, main frame by double-tone frequently demoder obtain the numbering of returning, by the numbering returned how much judge this heart yearn whether short circuit or open circuit, main frame detects the size that size of current on this heart yearn is calculated resistance simultaneously.Main frame is tested every heart yearn successively like this, and judgement cable that just can be complete connects situation.On LCDs, show testing result at last, or be sent to by computer interface on the special software of computing machine, carry out further analyzing and processing.In testing process, the main frame judgement send information to slave sometimes, requires slave also these two heart yearns to be connected on the voice signal processing unit, and shows that on LCDs talk line sets up the information of success, at this moment, the tester just can carry out communication each other.
Direct current signal and the double-audio signal form that has than strong anti-interference ability adopted in the signal transmission of above-mentioned design, the laying that adapts to shipboard cable detects, toll cable is equivalent to antenna after laying, there are many undesired signals to exist, if with digital signal and simple simulating signal, all cause Communications failure or error code easily, the confidence level of test result is reduced.And DC level is easy to eliminate to the interference of undesired signal, and double-audio signal is a kind of specific simulating signal, and that uses in phone at present is very extensive, and antijamming capability is very good.The design's voice communication line that can be dynamically connected certainly, convenient test contact, and multiple information output form is arranged, liquid crystal Chinese shows test process and carries reserve battery etc., improved the instrument practical value.
Description of drawings
Fig. 1 is the utility model design frame chart, and A represents the main frame member among the figure, and B represents the slave member, and D represents tested cable, and G represents common conductor.
Fig. 2 be microprocessor chip and with the wiring diagram of peripheral components link.
Fig. 3 is control circuit built-up circuit figure.
Fig. 4 is an audio output circuit.
Fig. 5 is the speech input circuit.
Fig. 6 is a power supply switch circuit.
Fig. 7 is a battery charging circuit.
Fig. 8 is LCD, keyboard interface circuit.
Fig. 9 is a RS232 computer interface circuit.
Figure 10 is a double-tone modulation-demodulation circuit frequently.
Figure 11 is the analog switch chip circuit.
Figure 12 is the cable interface circuit.
Figure 13 is the Control Software System block diagram.
Figure 14 measures process flow diagram for cable resistance.
Figure 15 is a cable situation process flow diagram.
Embodiment
This cable tester mainly is made up of eight parts: microprocessor, control circuit, voice signal processing unit (comprising speech input circuit, audio output circuit, double-tone modulation-demodulation circuit frequently), LCD display circuit, computer interface circuit, power supply automatic switchover circuit, battery charging circuit, cable interface circuit etc., as shown in Figure 1).
Below in conjunction with accompanying drawing embodiment is elaborated:
Microprocessor (A, B) as shown in Figure 2, microprocessor is the core of total system, chip is selected the ATMEGA103 microprocessor of American ATMEL for use, this chip functions is powerful, can give full play to its characteristics in system.The ATMEGA103 microprocessor internal contains the FLASH storer of 128K online programmable, can erasable repeatedly at least 1000 time, and the inside SDRAM of 4K, the EEPROM of 4K can be erasable repeatedly 10000 times, and data can be preserved 10 years after the power down.Can online programming, for the renewal of software has in the future brought convenience.Chip also has the A/D converter and the PWM output of 8 path 10 bit resolutions.The microprocessor handle sends detection signal, and accepts the cable condition information and handle, classify, show, be transferred to computing machine.
Control circuit A as shown in Figure 3, control circuit A comprises DC level generation circuit, crystal oscillating circuit, analog power filtering circuit, microprocessor programming Control circuit, real time clock circuit.DC level generation circuit provides the level of the cable detection about 4 volts for main frame, by diode D
1And D
2And resistance R
14And R
15Form two diode (D
1, D
2) and resistance R
14Form bleeder circuit, get level about 4V, R by the 5V power supply
15Play current limliting, cause when preventing cable short circuit that big electric current damages circuit.Crystal oscillating circuit is by Y
1, X
1And X
2Form, for microprocessor provides the work efficiency of 4MHZ, real time clock circuit is by Y
2And U
15Form, real-time system time is provided.Calendar chip is selected the PCF8653P chip for use, and this chip has the real-time clock function, uses I
2C communications protocol and microprocessor carry out communication, for system provides temporal information.Microprocessor programming Control circuit is by S
1, R
1, R
3 Form S
13,4 pin and microprocessor U
1The Vcc contact link to each other.
Audio output circuit as shown in Figure 4, audio output circuit is by U
11, R
12, R
13, C
17～
20Form, it can be monitored by loudspeaker in the cable tester test process, can engage in the dialogue by main frame and slave after test finishes.Circuit is selected for use the LM386 amplifier that the signal on the cable is amplified and is outputed to loudspeaker, by regulating R
13Can regulate the volume of loudspeaker.Circuit can be exported the power of 0.5W to 1W, and foot is in driving low power loudspeaker or earphone.
The speech input circuit as shown in Figure 5, the speech input circuit is by U
13, C
9～C
12, R
10And MK
1Form, pick up from Electret condenser microphone and be coupled to the equipment that cable is transferred to the other side after sound amplifies through one-level.Amplifying circuit also is to select the LM386 amplifier for use, connects into 200 times amplifying circuit, and voice signal is once amplified, and regulates adjustable resistance R
10Can regulate the size of output signal.
Double-tone frequently modulation-demodulation circuit as shown in figure 10, by U
2And U
12And peripheral resistance R
4～R
12, capacitor C
5～C
8, C
13～C
16And Y
3Form, main frame and from the digital signal of confidential transmission be modulated into double-tone frequently simulating signal transmit at cable, and the double-tone on the cable frequently simulating signal be demodulated to digital signal and send microprocessor to.Circuit is selected the MT8880 chip for use, this chip can be finished double-tone Code And Decode frequently, and the audio output of MT8880 is connected on the cable after one-level is amplified buffering, guarantees that double-tone frequency simulating signal has enough driving forces, waveform can distortion, can transmit larger distance.If disturbed, and be subjected to the influence of distance too big easily by the spike at scene when adopting the digital form transmission.
LCD show and keyboard interface circuit as shown in Figure 8, LCD demonstration and keyboard interface circuit provide good interface for the user, by display operation menu on LCD, test process information, and test result, the user is operating equipment very easily, the control and measuring process is checked test result.LCD display is selected 128 * 64 dot pattern displays for use, can select the more large-sized monitor of control chip of the same type for use if show more information.
The computer interface circuit as shown in Figure 9, the computer interface circuit couples together computing machine and microprocessor, it mainly is the effect of switching levels, select the MAX232 chip for use, this chip single supply (5V) power supply, can be standard RS232 conversion of signals the CMOS level, can be the CMOS level conversion standard RS232 signal simultaneously.Can operate equipment by computing machine, equipment can be transferred to computing machine to test result, is further processed analysis, shows to print.
Power supply automatic switchover circuit as shown in Figure 6, power supply automatic switchover circuit automatically switches to the Alternating Current Power Supply state when equipment is connected the alternating current 220V power supply, automatically switch to the powered battery state when losing AC power.Circuit is mainly finished by relay, selects double-contact 4 group relaies for use, and the indication of AC and DC power supply is arranged.
Battery charging circuit as shown in Figure 7, cable tester when work mainly by the powered battery that carries, the information that when battery electric quantity is not enough, can show the electric weight deficiency on the LCD, at this moment equipment needs charging, when the 220V AC power is connected, equipment automatically switches to 220V Alternating Current Power Supply state, and simultaneously battery is charged, insert the control end of U1 during charging by BAT-MOD, by microprocessor charging process is monitored, so that better charging and battery safeguarded prolongs the service time of battery.Charging circuit is by Q
1, Q
2, Q
3And R
20, R
21, R
22, R
23Form the switching pulse circuit, pulse signal is provided by microprocessor, L
1And C
27Form DC component and extract circuit, the direct supply of extraction is added on the battery, charges.R
24, R
25, R
26, R
29, C
28Form current detecting and voltage detecting circuit, electric current and information of voltage during the charging of battery offer microprocessor, and after the microprocessor acquisition process, whether the size and the charging of decision charging voltage should finish.
Cable interface circuit (A, B) is as Figure 11 and shown in Figure 12, and the cable interface circuit is mainly finished choosing of every chip in the cable, so that the analysis that microprocessor is finished every chip, circuit is selected HCF4067 16 path analoging switch chips for use, passes through U
374HC138 chooses each chip, by the core number that expansion HCF4067 can increase detection streamer, has selected 7 chip U in this equipment for use
4～U
10, Figure 12 has JX
1～JX
112Individual interface joins, and can detect the cable of 112 heart yearns.
The all functions of cable tester rely on software to realize, control all circuit by software and finish function corresponding.The theory diagram of software is the set of all control function of this machine as shown in figure 13, and each functional block has Control Software alone, as Figure 14, shown in Figure 15.It is vacant that cable one end connects the main frame other end, after starting test procedure, the DC level that the program of main frame produces DC level generation circuit by control analog switch chip circuit is added on the every heart yearn in the cable, detect the voltage at reference resistance two ends, program is converted to the resistance of heart yearn to concentric line or ground wire to the voltage on the reference resistance by the formula of having set in the program, and the preservation test result, be convenient to analyze.After having detected resistance, the other end of cable is connected on the slave, after starting test procedure, the program of main frame is by adding the direct current detection signal on the every heart yearn of control circuit in cable, the test procedure of slave is monitored every in cable heart yearn, if the direct current detection signal is arranged, just become the coded modulation of this heart yearn double-tone frequently to return to main frame through heart yearn by double-tone frequency modulation-demodulation circuit, one take turns detect finish after, slave sends thread-changing information to main frame, main frame adds the direct current detection signal on next root heart yearn, carry out the test of next round, main frame is collected from the testing result of slave by double-tone frequency modulation-demodulation circuit in test process, shows behind the statistical classification simultaneously, print and preserve.After finishing, detection on LCD, shows ending message.
The supervisory routine of charge in batteries that main frame and slave are inner integrated, the detection information that supervisory routine provides by testing circuit, be lower than certain setting value if detect the voltage of accumulator, just on LCD, show the not enough information of battery electric quantity, connected then started the Charge Management program if detect AC power, when charging current stops charging during less than certain setting value and show the charging information that finishes on LCD.
Claims (9)
1. cable tester, it comprises main frame and slave and the common conductor that is connected them, it is characterized in that main frame is made up of microprocessor A, voice signal processing unit A, control circuit A and AD converter, microprocessor A and voice signal processing unit A and control circuit A form series loop, input termination computer interface and the keyboard of microprocessor A, AD converter are connected between control circuit A output terminal and the microprocessor A; Slave is made up of microprocessor B, voice signal processing unit B and control circuit B, and microprocessor B and voice signal processing unit B and control circuit B form series loop, and display screen B is connected to the output terminal of microprocessor B; The cable connectivity port A of main frame links to each other with slave cable connectivity port B and forms the computer terminal detection system.
2. cable tester as claimed in claim 1 is characterized in that control circuit A comprises DC level generation circuit, crystal oscillating circuit, analog power filtering circuit, microprocessor programming Control circuit and real time clock circuit.
3. cable tester as claimed in claim 2 is characterized in that DC level generation circuit is by diode D
1And D
2And resistance R
14And R
15Form D
1D
2And R
14Form bleeder circuit, R
15Be current-limiting resistance.
4. cable tester as claimed in claim 2 is characterized in that microprocessor programming Control circuit is by S
1, R
1And R
3Form S
13,4 pin and microprocessor U
1The Vcc contact link to each other.
5. cable tester as claimed in claim 1 is characterized in that the voice signal processing unit comprises speech input circuit, audio output circuit and double-tone modulation-demodulation circuit frequently.
6. cable tester as claimed in claim 5 is characterized in that the speech input circuit is by U
13, C
9～C
12, R
10And MK
1Form.
7. cable tester as claimed in claim 5 is characterized in that audio output circuit is by U
11, C
17～C
20, R
12, R
13Form.
8. cable tester as claimed in claim 5 is characterized in that double-tone frequency modulation-demodulation circuit is by U
2And U
12And peripheral resistance R
4～R
12, capacitor C
5～C
8, C
13～C
16And Y
3Form.
9. cable tester as claimed in claim 1 is characterized in that cable connectivity port A, B are by 16 path analoging switch U
4～U
10And U
3And JX
2～JX
112Interface is connected to form.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02286887 CN2594802Y (en) | 2002-11-15 | 2002-11-15 | Digital capacitance meter with wide measurement range |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02286887 CN2594802Y (en) | 2002-11-15 | 2002-11-15 | Digital capacitance meter with wide measurement range |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2594802Y true CN2594802Y (en) | 2003-12-24 |
Family
ID=33747425
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02286887 Expired - Fee Related CN2594802Y (en) | 2002-11-15 | 2002-11-15 | Digital capacitance meter with wide measurement range |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2594802Y (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102141592A (en) * | 2010-12-28 | 2011-08-03 | 北京铁路信号有限公司 | Cable detection method and system |
| CN103063973A (en) * | 2012-12-24 | 2013-04-24 | 新乡职业技术学院 | Intelligent electricity wire signal-checking appliance |
| CN101937038B (en) * | 2009-07-02 | 2013-12-25 | 中国第一汽车集团公司无锡油泵油嘴研究所 | Intelligent multi-core cable harness detection device |
| CN102097717B (en) * | 2009-12-11 | 2014-04-30 | 上海卫星工程研究所 | Automatic detection switchover system for cable |
| CN103926525A (en) * | 2014-04-30 | 2014-07-16 | 广州视源电子科技股份有限公司 | System and method for obtaining quality information of main board of electronic product through voice |
| CN104506395A (en) * | 2015-01-09 | 2015-04-08 | 武汉精测电子技术股份有限公司 | Automatic detection device and detection method for communication wire |
| CN105242170A (en) * | 2015-11-23 | 2016-01-13 | 武汉工程大学 | Automatic aerial socket signal line number recognition method and device |
| CN106154099A (en) * | 2016-06-17 | 2016-11-23 | 林烨 | Cable tester and method of testing thereof |
| CN106761711A (en) * | 2016-12-26 | 2017-05-31 | 中石化江汉石油工程有限公司 | A kind of downhole instrument multifunctional communication control system |
| CN107154259A (en) * | 2017-04-27 | 2017-09-12 | 江门市新会区博上科技有限公司 | A kind of Application on Voiceprint Recognition door lock of sound receiving module and the application module |
| CN108037408A (en) * | 2017-12-05 | 2018-05-15 | 中国电力科学研究院有限公司 | A kind of system and method for detection cable conductor switching performance |
| CN111880120A (en) * | 2020-08-07 | 2020-11-03 | 成都微能铁信科技有限公司 | CIR multi-core control cable analysis recorder |
| CN116990725A (en) * | 2023-09-27 | 2023-11-03 | 成都电科星拓科技有限公司 | Cable in-place signal indication system and method |
-
2002
- 2002-11-15 CN CN 02286887 patent/CN2594802Y/en not_active Expired - Fee Related
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101937038B (en) * | 2009-07-02 | 2013-12-25 | 中国第一汽车集团公司无锡油泵油嘴研究所 | Intelligent multi-core cable harness detection device |
| CN102097717B (en) * | 2009-12-11 | 2014-04-30 | 上海卫星工程研究所 | Automatic detection switchover system for cable |
| CN102141592B (en) * | 2010-12-28 | 2014-07-30 | 北京铁路信号有限公司 | Cable detection method and system |
| CN102141592A (en) * | 2010-12-28 | 2011-08-03 | 北京铁路信号有限公司 | Cable detection method and system |
| CN103063973A (en) * | 2012-12-24 | 2013-04-24 | 新乡职业技术学院 | Intelligent electricity wire signal-checking appliance |
| CN103926525A (en) * | 2014-04-30 | 2014-07-16 | 广州视源电子科技股份有限公司 | System and method for obtaining quality information of main board of electronic product through voice |
| CN104506395A (en) * | 2015-01-09 | 2015-04-08 | 武汉精测电子技术股份有限公司 | Automatic detection device and detection method for communication wire |
| CN104506395B (en) * | 2015-01-09 | 2018-06-15 | 武汉精测电子集团股份有限公司 | Communicate wire rod automatic detection device and detection method |
| CN105242170B (en) * | 2015-11-23 | 2017-12-12 | 武汉工程大学 | The automatic identifying method and device of aviation socket signal wire numbering |
| CN105242170A (en) * | 2015-11-23 | 2016-01-13 | 武汉工程大学 | Automatic aerial socket signal line number recognition method and device |
| CN106154099A (en) * | 2016-06-17 | 2016-11-23 | 林烨 | Cable tester and method of testing thereof |
| CN106154099B (en) * | 2016-06-17 | 2019-12-27 | 林烨 | Cable tester and testing method thereof |
| CN106761711A (en) * | 2016-12-26 | 2017-05-31 | 中石化江汉石油工程有限公司 | A kind of downhole instrument multifunctional communication control system |
| CN106761711B (en) * | 2016-12-26 | 2024-02-02 | 中石化江汉石油工程有限公司 | Multifunctional communication control system for downhole instrument |
| CN107154259A (en) * | 2017-04-27 | 2017-09-12 | 江门市新会区博上科技有限公司 | A kind of Application on Voiceprint Recognition door lock of sound receiving module and the application module |
| CN108037408A (en) * | 2017-12-05 | 2018-05-15 | 中国电力科学研究院有限公司 | A kind of system and method for detection cable conductor switching performance |
| CN111880120A (en) * | 2020-08-07 | 2020-11-03 | 成都微能铁信科技有限公司 | CIR multi-core control cable analysis recorder |
| CN116990725A (en) * | 2023-09-27 | 2023-11-03 | 成都电科星拓科技有限公司 | Cable in-place signal indication system and method |
| CN116990725B (en) * | 2023-09-27 | 2023-12-12 | 成都电科星拓科技有限公司 | Cable in-place signal indication system and method |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| 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 |