CN110596511A - Low-frequency pulse signal line searching system - Google Patents
Low-frequency pulse signal line searching system Download PDFInfo
- Publication number
- CN110596511A CN110596511A CN201910796914.6A CN201910796914A CN110596511A CN 110596511 A CN110596511 A CN 110596511A CN 201910796914 A CN201910796914 A CN 201910796914A CN 110596511 A CN110596511 A CN 110596511A
- Authority
- CN
- China
- Prior art keywords
- low
- signal
- frequency pulse
- pulse signal
- frequency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention discloses a low-frequency pulse signal line-searching system, which comprises: the low-frequency pulse signal transmitting device and the low-frequency pulse signal receiving device are arranged on the base; the transmitting device comprises a signal generator and a transmitting connector, wherein the signal generator is used for generating low-frequency pulse signals, and the transmitting connector is used for transmitting the low-frequency pulse signals to a known cable; the receiving device comprises a signal receiver and a receiving connector, wherein the receiving connector is used for receiving unknown pulse signals transmitted by unknown cables, the signal receiver is used for measuring the waveform and the signal strength of the unknown pulse signals, the waveform of the unknown pulse signals conforms to the waveform of the low-frequency pulse signals, and one cable with the strongest signal strength is a cable corresponding to the known cable; the transmitting connector is a magnetic field coupling coil or an electric field coupling metal sheet or a direct contact wire, and the receiving connector is a magnetic field coupling coil or an electric field coupling metal sheet or a direct contact wire. The invention has the technical characteristics of strong anti-interference, high sensitivity, accurate judgment and strong universality.
Description
Technical Field
The invention belongs to the technical field of power system detection, and particularly relates to a low-frequency pulse signal line searching system.
Background
As technology advances, power systems become more powerful, and at the same time, power systems become more complex, especially with much more complex wiring. The routing equipment plays an important role in the routing equipment, and not only can assist the construction of early-stage wiring, but also can play an important role in daily maintenance and abnormal troubleshooting.
The presently known line finder has the following technical problems: the anti-interference ability is poor, the judgement condition is single not accurate, moreover to some cables overlength, can't follow the electric connection department at both ends and carry out hunting and detect.
Disclosure of Invention
The invention aims to provide a low-frequency pulse signal line-searching system which has the technical characteristics of strong anti-interference, high sensitivity, accurate judgment and strong universality.
In order to solve the problems, the technical scheme of the invention is as follows:
a low frequency pulse signal line-seeking system, comprising: the low-frequency pulse signal transmitting device and the low-frequency pulse signal receiving device are arranged on the base;
the low-frequency pulse signal transmitting device comprises a signal generator and a transmitting connector, wherein the signal generator is used for generating a low-frequency pulse signal, and the transmitting connector is used for transmitting the low-frequency pulse signal to a known cable;
the low-frequency pulse signal receiving device comprises a signal receiver and a receiving connector, wherein the receiving connector is used for receiving unknown pulse signals transmitted by unknown cables, the signal receiver is used for measuring the waveform and the signal strength of the unknown pulse signals, in a plurality of unknown cables, the waveform of the unknown pulse signals conforms to the waveform of the low-frequency pulse signals, and the cable with the strongest signal strength is the cable corresponding to the known cable;
the transmitting connector is a magnetic field coupling coil or an electric field coupling metal sheet or a direct contact wire, and the receiving connector is a magnetic field coupling coil or an electric field coupling metal sheet or a direct contact wire.
According to an embodiment of the invention, the signal receiver comprises a low noise amplifier, a 50Hz suppression circuit, a first low-pass filter, a signal amplifier, a shaping unit and a sampling unit;
the input end of the low-noise amplifier is used for receiving the unknown pulse signal and amplifying the unknown pulse signal with low noise, the output end of the low-noise amplifier is electrically connected with the input end of the 50Hz suppression circuit, the 50Hz power frequency suppression circuit is used for performing power frequency suppression on the signal, the output end of the 50Hz suppression circuit is electrically connected with the input end of the first low-pass filter, the first low-pass filter is used for filtering high-frequency noise in the signal, the output end of the first low-pass filter is electrically connected with the input end of the signal amplifier, the signal amplifier is used for performing amplification processing on the signal, the output end of the signal amplifier is electrically connected with the input end of the rectification unit, the shaping unit is used for shaping the signal to obtain the waveform of the unknown pulse signal, and the output end of the rectification unit is electrically connected with the input end of the sampling, the sampling unit is used for measuring and acquiring the waveform and the signal intensity of the unknown pulse signal.
According to an embodiment of the present invention, the signal amplifier is a gain controllable amplifier to satisfy signal amplification processing of different signal strengths.
According to an embodiment of the present invention, a second low-pass filter is further disposed between the output end of the rectifying circuit and the input end of the sampling unit, the output end of the rectifying circuit is electrically connected to the input end of the sampling unit through the second low-pass filter, and the second low-pass filter is configured to filter high-frequency noise in the shaped signal.
According to an embodiment of the present invention, the low frequency pulse signal is a low frequency signal with a cycle period T2, wherein the low frequency signal with a cycle period T2 includes a plurality of pulse signals with a cycle period T1, the period T1 is 100ms to 10s, and the period T2 is greater than or equal to 10 times the period T1.
Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages and positive effects:
the invention can detect unknown pulse signals on unknown cables by sending the low-frequency pulse signals to the known cables based on the low-frequency pulse signals, and can select the cables corresponding to the known cables according to the waveforms and the signal intensity, wherein, the transmitting connector and the receiving connector can be magnetic field coupling coils or electric field coupling metal sheets or direct contact wires, the magnetic field coupling coils wrap the cables based on the magnetic field coupling method for indirect signal transmission, the electric field coupling metal sheets wrap a section of length of cables based on the electric field coupling method for indirect signal transmission, the two types can realize signal transmission and reception without any destructive operation on the cables, can be suitable for a plurality of line hunting conditions, and simultaneously, the low-frequency pulse signals are selected to avoid high-frequency noise and improve the accuracy of signal transmission, and the judgment is more accurate by utilizing the waveform and signal intensity double-condition hunting, the technical effects of strong interference resistance, high sensitivity, accurate judgment and strong universality are achieved.
Drawings
FIG. 1 is a schematic diagram of an entire low frequency pulse signal line-seeking system according to the present invention;
FIG. 2 is another overall schematic diagram of a low frequency pulse signal tracking system according to the present invention;
FIG. 3 is a schematic diagram of a low-frequency pulse signal line-seeking system according to the present invention;
FIG. 4 is a schematic diagram of a low-frequency pulse signal receiving device of a low-frequency pulse signal line-seeking system according to the present invention;
FIG. 5 is a circuit diagram of a low noise amplifier of a low frequency pulse signal tracking system according to the present invention;
FIG. 6 is a circuit diagram of a 50Hz suppression circuit of a low frequency pulse signal tracking system according to the present invention;
FIG. 7 is a circuit diagram of a first low-pass filter of a low-frequency pulse signal tracking system according to the present invention;
FIG. 8 is a circuit diagram of a signal amplifier of a low frequency pulse signal tracking system according to the present invention;
FIG. 9 is a circuit diagram of a second low pass filter of a low frequency pulse signal tracking system according to the present invention;
fig. 10 is a circuit diagram of a shaping unit and a sampling unit of a low frequency pulse signal line-seeking system according to the present invention.
Description of reference numerals:
1: a low-frequency pulse signal transmitting device; 2: a low-frequency pulse signal receiving device; 3: a magnetic field coupling coil; 4: an electric field coupling metal sheet; 5: directly contacting the wire; 6: a known cable; 7: an unknown cable.
Detailed Description
The following describes a low-frequency pulse signal line-seeking system according to the present invention in further detail with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following description and from the claims.
Referring to fig. 1 and 2, the present embodiment provides a low frequency pulse signal line-seeking system, including: a low-frequency pulse signal transmitting device 1 and a low-frequency pulse signal receiving device 2;
the low-frequency pulse signal transmitting device 1 comprises a signal generator and a transmitting connector, wherein the signal generator is used for generating a low-frequency pulse signal, and the transmitting connector is used for transmitting the low-frequency pulse signal to a known cable 6;
the low-frequency pulse signal receiving device 2 comprises a signal receiver and a receiving connector, wherein the receiving connector is used for receiving unknown pulse signals transmitted by unknown cables 7, the signal receiver is used for measuring the waveform and the signal strength of the unknown pulse signals, and in the unknown cables 7, the waveform of the unknown pulse signals accords with the waveform of the low-frequency pulse signals, and one cable with the strongest signal strength is a cable corresponding to the known cable 6;
the transmitting connector is a magnetic field coupling coil 3 or an electric field coupling metal sheet 4 or a direct contact wire 5, and the receiving connector is a magnetic field coupling coil 3 or an electric field coupling metal sheet 4 or a direct contact wire 5.
The present embodiment will now be described in detail:
specifically, referring to fig. 1 and fig. 2, the hunting system of the present embodiment includes a low-frequency pulse signal transmitting device 1 and a low-frequency pulse signal receiving device 2, where the transmitting end is installed on a known fixed cable, the receiving section is installed on an unknown cable end, and the relationship between the known cable and the unknown cable is determined by detecting and comparing the differences of signals received by different undetermined cables, and further, the relationship between the known cable and the unknown cable is determined according to the strength and waveform of the signals.
Specifically, a low-frequency pulse periodic signal is loaded on a known cable in two ways of direct contact or inductive contact, and the low-frequency pulse periodic signal is received at a receiving end by using an inductive contact or direct contact method, and the current signal strength is measured. Further, the signal transmission method of the inductive contact may be a magnetic field coupling method and an electric field coupling method, that is, the signal transmission method corresponds to the magnetic field coupling coil 3 and the electric field coupling metal sheet 4 of this embodiment: the electromagnetic coupling is that the mutual inductance exists between the two circuits, so that the current change of one circuit affects the other circuit through the mutual inductance, and the practical detachable coil-wrapped cable in the embodiment transmits and receives low-frequency pulse signals by using the mutual inductance; the electric field coupling is a coupling mode generated due to the existence of the distributed capacitance, and in the embodiment, the metal sheet wraps a certain length of cable to form the distributed capacitance so as to transmit and receive the low-frequency pulse signal. The direct contact signal transmission mode corresponds to the direct contact wire 5 of this embodiment, and the direct and guide electrical connection can realize the transmission and reception of the low-frequency pulse signal. Generally, at the end points of the cable, the metal layer of the cable is exposed, a direct contact wiring method can be used, and at the middle end of the cable, the cable cannot be subjected to destructive operation, and only an indirect contact method can be used for contact.
Preferably, referring to fig. 4, the signal receiver includes a low noise amplifier, a 50Hz suppression circuit, a first low pass filter, a signal amplifier, a shaping unit, and a sampling unit;
the input end of the low-noise amplifier is used for receiving unknown pulse signals and amplifying the unknown pulse signals in low noise, the output end of the low-noise amplifier is electrically connected with the input end of the 50Hz suppression circuit, the 50Hz power frequency suppression circuit is used for performing power frequency suppression on the signals, the output end of the 50Hz suppression circuit is electrically connected with the input end of the first low-pass filter, the first low-pass filter is used for filtering high-frequency noise in the signals, the output end of the first low-pass filter is electrically connected with the input end of the signal amplifier, the signal amplifier is used for performing amplification processing on the signals, the output end of the signal amplifier is electrically connected with the input end of the rectification unit, the shaping unit is used for shaping the signals to obtain waveforms of the unknown pulse signals, the output end of the rectification unit is electrically connected with the input end of the.
Specifically, in the receiving device, signals can be accessed through 2 indirect contact wiring methods or a direct contact wire 5, then the signals are subjected to low-noise amplification, then the signals pass through a 50Hz power frequency suppression circuit, then a low-pass filter is carried out, further amplification processing of the signals is carried out, then signal shaping processing is carried out, the shaped signals are subjected to signal waveform and intensity sampling measurement, and then the connection relation between the known cable and the unknown cable can be judged. Because a low-frequency signal is used, high-frequency noise in the space is greatly filtered by using a low-pass filter, and the receiving sensitivity is enhanced.
The wave form after shaping accords with the emission wave form, the wave form is the same signal, each cable of the present position is processed by the signal intensity measurement, when the wave form is consistent, and the cable with the strongest intensity is the cable that we need to find, the emission end and the receiving section are on the same cable.
Preferably, referring to fig. 3, the low frequency pulse signal is a low frequency signal with a cycle period T2, wherein the low frequency signal with the cycle period T2 includes a plurality of pulse signals with the cycle period T1, T1 is 100ms to 10s, and T2 is greater than or equal to 10 times T1.
Specifically, the transmitting circuit transmits a low-frequency periodic pulse signal, the shape of the signal is as shown in the figure, the low-frequency pulse generating circuit continuously transmits a signal with a cycle period of T2, n pulse signals with a cycle period of T1 are firstly performed in T2, and the duty ratio is 1: 1, low level for a certain period of time in the latter half of T2. Here, T1 is selected to be 100ms to 10s, and T2 is selected to be ≥ 10T1.
Preferably, the signal amplifier is a gain controllable amplifier to satisfy signal amplification processing of different signal strengths. In order to satisfy the signal amplification processing of different signal strengths, the signal amplifier of this embodiment employs a gain-controllable amplifier, and the amplification gain can be adjusted to cope with unknown pulse signals with weak signals and excessively strong signals.
Preferably, a second low-pass filter is further arranged between the output end of the rectifying circuit and the input end of the sampling unit, the output end of the rectifying circuit is electrically connected with the input end of the sampling unit through the second low-pass filter, and the second low-pass filter is used for filtering high-frequency noise in the shaped signal so as to improve the diagnosis accuracy of the unknown pulse signal.
The embodiment is based on low-frequency pulse signals, the low-frequency pulse signals are sent to known cables, the unknown pulse signals are detected on the unknown cables, and the cables corresponding to the known cables can be selected according to waveforms and signal strength, wherein the transmitting connector and the receiving connector can be magnetic field coupling coils or electric field coupling metal sheets or direct contact wires, the magnetic field coupling coils wrap the cables based on a magnetic field coupling method to carry out indirect signal transmission, the electric field coupling metal sheets wrap a section of cable with a length based on the electric field coupling method to carry out indirect signal transmission, the two types of the signals can realize signal transmission and reception without any destructive operation on the cables, the method is suitable for line seeking conditions of a plurality of lines, meanwhile, the low-frequency pulse signals are subjected to line selection, high-frequency noise can be avoided, the accuracy of signal transmission is improved, line seeking is realized by using the waveforms and the signal strength, the judgment is more accurate, the technical effects of strong interference resistance, high sensitivity, accurate judgment and strong universality are achieved.
The specific circuit will now be explained:
the low-frequency pulse signal transmitting device of the present embodiment may be a low-frequency signal generator in which an RC oscillator and a difference frequency oscillator are main oscillator stages, or may be a function generator or a pulse signal generator. Further, the present embodiment employs a generator that generates rectangular pulses with adjustable width, amplitude and repetition frequency.
Specifically, referring to fig. 5, the low noise amplifier of this embodiment employs two-stage amplification, where the first stage of low noise amplification employs an AD620 amplifier U1, IN + and IN-are input terminals of unknown pulse signals, R4 is a resistor for setting gain, the second season of the low noise amplifier employs a TL084 amplifier U3, a cathode of the TL084 amplifier is electrically connected to an output terminal of the AD620 amplifier via a resistor R3, an anode of the TL084 amplifier is grounded via a resistor R1, and cathodes of the TL084 amplifier are electrically connected to an output terminal of the TL084 amplifier via a parallel resistor R7 and a capacitor C4, respectively.
Specifically, referring to fig. 6, the 50Hz suppression circuit of this embodiment employs a 50Hz harmonic filter, wherein an input terminal of the 50Hz suppression circuit is electrically connected to one ends of a capacitor C1 and a resistor R5, respectively, the other end of C1 is grounded via a resistor R2, the other end of C1 is further electrically connected to one end of a capacitor C2, the other end of R5 is connected to one ends of a resistor R6 and a capacitor C3, respectively, the other end of C2 and the other end of R6 are electrically connected to an anode of an operational amplifier U4, the other end of C3 is electrically connected to an output terminal of U4, a cathode of U4 is grounded via a resistor R8, a cathode of U4 is further electrically connected to one end of a resistor R9, and the other end of R9 is electrically connected to an output.
Specifically, referring to fig. 7, the first low-pass filter of the present embodiment is designed as follows: the input end of the first low-pass filter is electrically connected with one end of a capacitor C6, one end of a resistor R16 and one end of a resistor R19 through a resistor R15, the other end of the C6 is grounded, the other end of the R16 is electrically connected with the negative electrode of an operational amplifier U6 and one end of a capacitor C10, the other end of the R19 is electrically connected with the other end of the C10 and the output end of the U6, and the positive electrode of the U6 is grounded.
Specifically, referring to fig. 8, the signal amplifier of this embodiment employs a gain-controllable amplifying capacitor, wherein the input terminal of the signal amplifier is electrically connected to the negative terminal of the operational amplifier U5 and one end of the programmable resistor R20 through a resistor R14, the positive terminal of the operational amplifier U5 is grounded through a resistor R10, and the other end of the operational amplifier R20 is electrically connected to the output terminal of the operational amplifier U5. The gain of the signal amplifier can be controlled by adjusting the resistance value of the R20.
Specifically, referring to fig. 9, the shaping unit of the present embodiment adopts the following design: the input end of the shaping unit is respectively and electrically connected with one end of a capacitor C7, a resistor R17 and a resistor R11 through a diode D1, the other end of C7 and the other end of R17 are respectively grounded, the other end of R11 is grounded through a capacitor C8, and the other end of R11 is used as the output end of the rectifying circuit.
Specifically, referring to fig. 10, the second low-pass filter of the present embodiment is designed as follows: the input end of the second low-pass filter is electrically connected with one end of a capacitor C5, one end of a resistor R13 and one end of a resistor R18 through a resistor R12, the other end of the C5 is grounded, the other end of the R13 is electrically connected with the negative electrode of the operational amplifier and one end of a capacitor C9, the other end of the R18 is electrically connected with the other end of the C9 and the output end of the U7, and the positive electrode of the U7 is grounded.
Specifically, referring to fig. 10, the sampling unit of this embodiment directly samples an unknown pulse signal by using an analog-to-digital converter, and the sampled data is transmitted to the MCU for diagnosing the signal strength and waveform.
The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, it is still within the scope of the present invention if they fall within the scope of the claims of the present invention and their equivalents.
Claims (5)
1. A low frequency pulse signal hunting system, comprising: the low-frequency pulse signal transmitting device and the low-frequency pulse signal receiving device are arranged on the base;
the low-frequency pulse signal transmitting device comprises a signal generator and a transmitting connector, wherein the signal generator is used for generating a low-frequency pulse signal, and the transmitting connector is used for transmitting the low-frequency pulse signal to a known cable;
the low-frequency pulse signal receiving device comprises a signal receiver and a receiving connector, wherein the receiving connector is used for receiving unknown pulse signals transmitted by unknown cables, the signal receiver is used for measuring the waveform and the signal strength of the unknown pulse signals, in a plurality of unknown cables, the waveform of the unknown pulse signals conforms to the waveform of the low-frequency pulse signals, and the cable with the strongest signal strength is the cable corresponding to the known cable;
the transmitting connector is a magnetic field coupling coil or an electric field coupling metal sheet or a direct contact wire, and the receiving connector is a magnetic field coupling coil or an electric field coupling metal sheet or a direct contact wire.
2. The low-frequency pulse signal line hunting system according to claim 1, wherein the signal receiver comprises a low noise amplifier, a 50Hz suppression circuit, a first low pass filter, a signal amplifier, a shaping unit, and a sampling unit;
the input end of the low-noise amplifier is used for receiving the unknown pulse signal and amplifying the unknown pulse signal with low noise, the output end of the low-noise amplifier is electrically connected with the input end of the 50Hz suppression circuit, the 50Hz power frequency suppression circuit is used for performing power frequency suppression on the signal, the output end of the 50Hz suppression circuit is electrically connected with the input end of the first low-pass filter, the first low-pass filter is used for filtering high-frequency noise in the signal, the output end of the first low-pass filter is electrically connected with the input end of the signal amplifier, the signal amplifier is used for performing amplification processing on the signal, the output end of the signal amplifier is electrically connected with the input end of the rectification unit, the shaping unit is used for shaping the signal to obtain the waveform of the unknown pulse signal, and the output end of the rectification unit is electrically connected with the input end of the sampling, the sampling unit is used for measuring and acquiring the waveform and the signal intensity of the unknown pulse signal.
3. The system according to claim 2, wherein the signal amplifier is a gain controllable amplifier to satisfy signal amplification processing of different signal strengths.
4. The system according to claim 2, wherein a second low pass filter is further disposed between the output terminal of the rectifying circuit and the input terminal of the sampling unit, the output terminal of the rectifying circuit is electrically connected to the input terminal of the sampling unit through the second low pass filter, and the second low pass filter is configured to filter out high frequency noise in the shaped signal.
5. The low-frequency pulse signal line hunting system according to claim 1 or 2, wherein the low-frequency pulse signal is a low-frequency signal with a cycle period T2, wherein a plurality of pulse signals with a cycle period T1 are included in the low-frequency signal with a cycle period T2, the T1 is 100ms to 10s, and the T2 is greater than or equal to 10 times the T1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910796914.6A CN110596511A (en) | 2019-08-27 | 2019-08-27 | Low-frequency pulse signal line searching system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910796914.6A CN110596511A (en) | 2019-08-27 | 2019-08-27 | Low-frequency pulse signal line searching system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110596511A true CN110596511A (en) | 2019-12-20 |
Family
ID=68855917
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910796914.6A Pending CN110596511A (en) | 2019-08-27 | 2019-08-27 | Low-frequency pulse signal line searching system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110596511A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112992330A (en) * | 2021-02-25 | 2021-06-18 | 未来穿戴技术有限公司 | Signal processing method, massager, mobile terminal and display device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2045955A (en) * | 1979-03-16 | 1980-11-05 | Minnesota Mining & Mfg | System and method for locating resistive faults and interconnest errors in multi-conductor cables |
| CN203551706U (en) * | 2013-09-17 | 2014-04-16 | 东莞市杰创电子测控科技有限公司 | Novel noiseless hunting instrument |
| CN104407272A (en) * | 2014-12-16 | 2015-03-11 | 国家电网公司 | Cable identification device |
| CN105826906A (en) * | 2016-04-29 | 2016-08-03 | 优利德科技(中国)有限公司 | Method and device for hunting power frequency power circuit corresponding to protector |
| CN109884477A (en) * | 2019-03-08 | 2019-06-14 | 武汉鸿志高测电气技术有限公司 | Identify the instrument and method of power cable |
-
2019
- 2019-08-27 CN CN201910796914.6A patent/CN110596511A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2045955A (en) * | 1979-03-16 | 1980-11-05 | Minnesota Mining & Mfg | System and method for locating resistive faults and interconnest errors in multi-conductor cables |
| CN203551706U (en) * | 2013-09-17 | 2014-04-16 | 东莞市杰创电子测控科技有限公司 | Novel noiseless hunting instrument |
| CN104407272A (en) * | 2014-12-16 | 2015-03-11 | 国家电网公司 | Cable identification device |
| CN105826906A (en) * | 2016-04-29 | 2016-08-03 | 优利德科技(中国)有限公司 | Method and device for hunting power frequency power circuit corresponding to protector |
| CN109884477A (en) * | 2019-03-08 | 2019-06-14 | 武汉鸿志高测电气技术有限公司 | Identify the instrument and method of power cable |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112992330A (en) * | 2021-02-25 | 2021-06-18 | 未来穿戴技术有限公司 | Signal processing method, massager, mobile terminal and display device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101487810B (en) | Soil three-parameter measuring method and system | |
| CN201673231U (en) | Fault testing apparatus of cable or pipeline | |
| CN106841815B (en) | Power line iron tower grounding resistance on-line tester based on voltage excitation | |
| CN106124939A (en) | Distributed high tension cable partial discharge monitoring and alignment system | |
| CN105823922B (en) | Hum bar electrical induction device | |
| CN102981110A (en) | Data measurement and storage system and method for achieving high frequency and ultra-high frequency partial discharge monitoring of transformer | |
| CN113092925A (en) | Power distribution network topological structure recognition device | |
| CN110596511A (en) | Low-frequency pulse signal line searching system | |
| AU4358299A (en) | Method and device for monitoring an electrode line of a bipolar high voltage direct current (hvdc) transmission system | |
| US2291533A (en) | Trouble finder cable tone device | |
| CN203037802U (en) | Data measuring storage system achieving transformer high-frequency and ultrahigh-frequency partial discharge monitoring | |
| CN110632550A (en) | Smart electric meter wiring terminal poor contact detection method, circuit and device | |
| CN116448216B (en) | Program-controlled ultrasonic liquid level meter transmitting circuit, receiving circuit and ranging system | |
| CN116593842A (en) | Cable partial discharge detection system and method with broadband and filtering functions | |
| CN109061260B (en) | Method for preventing electricity stealing by strong magnetism | |
| CN102095924A (en) | Detection device for power utilization and measurement of high-voltage circuit | |
| EP1402709B1 (en) | Detecting a bridge tap or end-of-line of a telephone line using time-domain reflectometry | |
| CN212514952U (en) | Comprehensive line inspection device for low-voltage cable | |
| EP0898173B1 (en) | A device for detecting faults in an electric line of a vehicle, in particular a commercial vehicle | |
| CN106597113B (en) | Power line iron tower ground resistance on-line tester based on proportion detection | |
| CN219456313U (en) | Current monitoring device of high-power artificial source electromagnetic detection system | |
| CN216595370U (en) | High-frequency pulse sensor for partial discharge of delay line | |
| CN217739316U (en) | Cable line cross-connection loop metal shielding resistor live-line detection system | |
| CN220794361U (en) | Blast furnace burden level detecting system | |
| CN112946438A (en) | Modularized wireless partial discharge detection device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20191220 |
|
| RJ01 | Rejection of invention patent application after publication |