CN105303927A - Medium-voltage cable electrical test skill training system - Google Patents

Abstract

The invention discloses a medium-voltage cable electrical test skill training system with functions of cable insulation resistance measurement, main dielectric strength test, fault distance detection, cable identification/path finding, fault point fixation, cable fault simulation and typical case waveform analysis and the like. According to the design scheme, a mechanical structure, electrical connection, control interfaces, software design and the like of the system are optimized, and centralized configuration of various cable testing functions is realized in the system. An experiment test result shows that the system is complete in function and reliable in operation, functions are switched conveniently and quickly, and tasks and requirements of cable comprehensive test training are met. The system is controlled by a computer on a worktable in a unified mode, and operation interfaces of various units can run independently after being invoked by a main operation interface. The system can provide a simulation environment for trainees to test cables in field, and can be reused, strict requirements of a test environment with complicated conditions are solved effectively, and training effect and safety factors are greatly improved.

Description

Midium voltage cable electric test skills training system

Technical field

The present invention relates to a kind of power cable integration test training system, especially a kind of midium voltage cable electric test skills training system.

Background technology

At present, the cable testing equipment of existing various function both at home and abroad, as cable-insulating voltage-withstanding testing, cable fault localization, cable trace such as to search at the equipment.But these are all adapted to rig-site utilization and design, therefore, develop a kind of complete function, simple operation, formation rational cable integration test training apparatus become cable training department problem demanding prompt solution.

Summary of the invention

The technical problem to be solved in the present invention is to provide a kind of midium voltage cable electric test skills training system that can realize comprehensive training to wireline test human users technical ability.

In order to solve the problems of the technologies described above, the present invention includes

Operation control module, it is made up of the function switch/adjusting knob on industrial computer and control panel, for controlling and regulating other functional module work;

Major insulation voltage-withstand test module, adopts the resistance to die block of frequency modulation series resonance voltage-resisting test apparatus design cable major insulation, and uses series resonance principal to carry out dielectric voltage withstand test to cable;

High/low pressure signal generator module, comprises high direct voltage signal generator and AC low-tension signal generator, and this module can coordinate carries out cable fault localization, position determination of fault, cable discriminating/path searching;

Fault localization module, it comprises impulse method fault locator and electric-resistivity method fault locator, and impulse method fault locator is used for the range finding of Low Voltage Impulse Method, pulse current method and secondary pulse process, and electric-resistivity method fault locator is used for the fault localization of protective coverings of cable;

Cable discriminating/path searching module, its AC low-tension signal generator coordinate under can to charged/not live electric cable differentiate and path searching;

Position determination of fault module, it forms primarily of type cable failure positioning instrument, comprises main frame, probe and earphone, and the synchronous record principle of this module utilization sound magnetic signal carries out position determination of fault;

Insulation measurement module, primarily of megohmmeter and ohmmeter composition, wherein, megohmmeter is provided with 500V, 1000V, 2500V and 5000V and measures gear, have startup self-detection and self-correcting function, ohmmeter have employed ADAM-4017 multichannel analog amount acquisition module and realizes resistance measurement function.

The invention has the beneficial effects as follows: system of the present invention has been gone out to drill in integral work table, system controls by the computing machine on worktable is unified, and the operation interface of each unit can independent operating separately after main operation interface is called.This system can provide the simulated environment of student's on-the-spot test cable, can reuse, and effectively solves the rigors of experimental enviroment complicated condition, substantially increases result of training and safety factor.In addition, this system achieves the comprehensive training to wireline test human users technical ability.The functions such as system configuration insulating resistance of cable measurement, major insulation withstand voltage test, fault localization, cable discriminating/path searching, position determination of fault and cable fault emulation and typical case wave form analysis.Design proposal is optimized from aspects such as physical construction, electrical connection, operation and control interface and Software for Designs, achieves the centralized configuration of multiple wireline test function in set of system.Experimental results shows that this systemic-function is complete, reliable operation, convenient functional conversion quick, meets task and the requirement of cable integration test training.

Accompanying drawing explanation

Fig. 1 is system functional block diagram of the present invention;

Fig. 2 is frequency modulation series resonance test philosophy figure of the present invention;

Fig. 3 is high/low pressure signal generator module operation interface schematic diagram in the present invention;

Fig. 4 is electric-resistivity method sheath fault localization schematic diagram in the present invention;

Fig. 5 be in the present invention sound magnetic signal with one-step site schematic diagram;

Fig. 6 is ohmmeter fundamental diagram in the present invention;

Fig. 7 is whole software structure schematic diagram in the present invention;

Fig. 8 is II cable A phase fault ranging waveform in the present invention;

Fig. 9 is II cable B phase fault ranging waveform in the present invention.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation:

See Fig. 1 to Fig. 9, the present invention designs and develops a kind of power cable integration test training system, is used for carrying out technology and practical operation training and checking system to power cable test personnel and troubleshooting personnel.The major function of equipment has:

1, the hardware design of system

1.1 system architectures and principle of work

System mainly comprises insulation measurement, major insulation voltage-withstand test, high/low pressure signal generation, fault localization, cable discriminating/path searching, position determination of fault, operation control and the module such as fault simulation and the wave form analysis of cable typical case.Its functional block diagram as shown in Figure 1.

Entire system is control desk structure.Its industrial computer, display and various function switch/adjusting knob are arranged on control desk front panel, form operation control module.Other functional modules are installed or are placed on control desk inside.Power supply and the test guide wire of system are drawn from control desk rear portion.

Operation control module forms primarily of the function switch on 1# industrial computer and control panel/adjusting knob, for controlling and regulating other functional module work.As high/low pressure signal generator module is controlled by the switch on control desk panel and knob by tester, export test signal according to test mode and adjustment parameter, coordinate and carry out cable fault localization, cable discriminating, path searching and position determination of fault.Cable discriminating/path searching module and position determination of fault module are portable testing set, be placed on control desk inside at ordinary times, scene is carried into by tester during training, fault simulation and typical case wave form analysis module are made up of 2# industrial computer, are found range and wave form analysis to simulated failure by software.In addition, connected by network interface, 2# industrial computer can also get off the fault localization Waveform storage of 1# industrial computer actual measurement, carries out wave form analysis and localization of fault training for tester.

1.2 major insulation voltage-withstand test modules

Adopt the resistance to die block of frequency modulation series resonance voltage-resisting test apparatus design cable major insulation herein.Use series resonance principal to carry out dielectric voltage withstand test to cable, have and easily realize hands-off tuning, quality factor are high, lightweight, power supply capacity require little, with the advantage such as power frequency withstand test equivalence is good, be current most widely used ac voltage withstanding method of testing.[4]

According to series resonance principal, under sinusoidal excitation, when R, L, C series circuit port voltage U and the same phase time of electric current I, circuit generation resonance.The condition of circuit resonance can be expressed as

Im[Z(jω)]＝0(1)

In formula

$Z\left(\mathrm{j\ω}\right)=R+\mathrm{j\ωL}-j\frac{1}{\mathrm{\ωC}}---\left(2\right)$

For circuit port impedance.Therefore, have during circuit resonance

$\mathrm{\ωL}-\frac{1}{\mathrm{\ωC}}=0---\left(3\right)$

ω is the resonance angular frequency of R, L, C series circuit, can solve

$\mathrm{\ω}=\frac{1}{\sqrt{\mathrm{LC}}}---\left(4\right)$

By ω=2 π f, can obtain resonance frequency is

$f=\frac{1}{2\mathrm{\π}\sqrt{\mathrm{LC}}}---\left(5\right)$

The quality factor of resonant circuit are

$Q=\frac{1}{R}\sqrt{\frac{L}{C}}---\left(6\right)$

During resonance, the voltage U C on the electric current I of series circuit and electric capacity is respectively

I＝U/R(7)

U _C＝-jQU(8)

Namely the voltage on electric capacity is Q times of series circuit port voltage.Therefore, by adjusting the frequency of pumping signal, whether the way of Detection capacitance voltage max, decision circuitry can there occurs resonance simultaneously.In addition, port voltage U and electric current I homophase during resonance, the active power W=UI that circuit absorbs, and the reactive power that circuit absorbs is zero.

Because series resonance can obtain higher quality factor, and power supply only needs to export less active power, therefore series resonance testing device can obtain the output of high voltage large capcity on capicitive sample with the power supply of low capacity low-voltage, is applicable to very much carrying out ac voltage withstanding test to power cable.

Herein for the test training requirement of 6kV ~ 35kV electric pressure cable, configuration frequency modulation series resonance formula major insulation voltage-withstand test module.According to the suggestion of international conference on large HV electric systems (CIGRE) the 21st, 09 working group, resonance frequency is selected within the scope of 30Hz ~ 300Hz.During test, first module regulates the output frequency of variable-frequency power sources, by the feedback voltage signal of Detection capacitance voltage divider, find the resonance frequency of circuit, make module reactance and electric cable capacitance generation resonance, and then by adjusting the output voltage of exciting transformer, making the trial voltage that resonance potential reaches required, finally carrying out voltage-withstand test.The principle of work of frequency modulation series resonance as shown in Figure 2.

In addition, for the ease of training, the manual/auto selectable operator scheme of system, carries out resonance frequency search and boosting adjustment; In order to ensure the safety of start-up and equipment, module has perfect defencive function, comprises overvoltage protection, overcurrent protection, overheating protection and wiring error protection.

1.3 high/low pressure signal generator modules

High/low pressure signal generator module is the vitals of system, comprises high direct voltage signal generator and AC low-tension signal generator.In order to adapt to the needs of integration test, design proposal being provided with is adapted to conversion and regulatory function, this module is coordinated and carries out cable fault localization, position determination of fault, cable discriminating/path searching.

During work, select high direct voltage signal generator or AC low-tension signal generator function with high-low pressure switch.

When selecting high direct voltage signal generator function, module mainly contains 3 kinds of functions:

1) second pulse working method is selected with test mode switch, select the impulse capacitor (respectively the highest 32kV, 16kV, 8kV maximum output voltage of correspondence) of 4 μ F, 16 μ F or 64 μ F with combination capacitor switch, select impulse discharge or periodic discharging mode by operational mode switch.Be provided with rear high pressure adjustment knob and boost to suitable voltage, finally by the electric discharge of Manual press impulse discharge button, or by High-voltage Signal Generator automatic discharging, module can coordinate carries out impulse method fault localization.

2) with the 1st) to plant arranging of function similar, if test mode strobe pulse current work mode, working mode selection periodic discharging, High-voltage Signal Generator is periodically to cable applying impacting with high pressure signal, and module can coordinate carries out position determination of fault.

3) select direct current mode by operational mode switch, then boost to suitable voltage with high pressure adjustment knob, module can carry out the test of cable sheath DC break down voltage, and electric-resistivity method fault locator also can be coordinated to carry out fault localization.

When selecting AC low-tension signal generator function, tester passes through the frequency button selection signals output frequency on control desk panel, by continuously/interrupted button selection signals way of output.By the power that power+and power-button adjustment output signal, finally by clamp or direct-connected button selection signals to the coupling scheme of cable, module can to charged or not live electric cable export continuous/interrupted AC signal of multi-frequency, cable identifier/path instrument is coordinated to carry out the discriminating of cable, and the searching of cable trace.

The operation interface of high/low pressure signal generator module as shown in Figure 3.

1.4 fault localization modules

Fault localization module is mainly containing impulse method fault locator and electric-resistivity method fault locator.

Impulse method fault locator has Low Voltage Impulse Method, pulse current method and secondary pulse process distance measurement function [3].Equipment is initiatively launched or passive return pulse signal, as long as know the speed V that pulsating wave is propagated in the cable, then measure the time Δ T obtaining pulsating wave roundtrip propagation between equipment and trouble spot and once experience, can measure according to formula and obtain fault distance S.

$S=\frac{1}{2}\mathrm{V\ΔT}---\left(9\right)$

Electric-resistivity method fault locator is mainly used in the fault localization of protective coverings of cable.Because protective coverings of cable dielectric level is low, cannot apply impacting with high pressure signal, and pulsating wave propagation attenuation in the earth is serious, therefore outer jacket fault is difficult to utilize pulsating wave to find range, but adopts electric-resistivity method to find range.During range finding, the cable sheath of fault and good heart yearn are linked together at cable far-end with short circuit ring, with high direct voltage signal generator as direct voltage source E, by sheath trouble spot to the earth Injection Current I, then measure the voltage U between sheath and heart yearn at test lead.Because trouble spot is flow through by no current on short circuit ring to the circuit of heart yearn, therefore trouble spot and test lead heart yearn termination equipotential, voltage U is the pressure drop that electric current I produces when flowing through between trouble spot and sheath test lead, obtains the sheath resistance R between trouble spot and test lead

R＝U/I(10)

According to the resistance ρ of sheath unit length, the distance L of cable sheath fault can be obtained

L＝R/ρ(11)

The principle of electric-resistivity method fault localization as shown in Figure 4.

1.5 cable discriminating/path searching modules

Cable discriminating/path searching module AC low-tension signal generator coordinate under can to charged/not live electric cable differentiate and path searching.This equipment has 500Hz, 1kHz, 8kHz, 33kHz, 66kHz, 93kHz totally 6 kinds of frequency signal active probe abilities and power frequency and radiofrequency signal passive detection ability, owing to have employed extremely narrow Signal reception passband and perfect digital signal processing method, equipment antijamming capability is strong, works under being adapted at various different industry spot condition.In addition, this equipment has left and right directions deixis, intuitively can show the position of cable on a liquid crystal display; There is path trace to correct errors prompt facility, effectively get rid of the interference closing on cable induction magnetic field; There is cable depth measurement function, directly read the buried depth of cable by liquid crystal display; With the use of caliper brake current transformer, uniqueness discriminating can be carried out to cable.

1.6 position determination of fault modules

Position determination of fault module forms primarily of type cable failure positioning instrument, comprises main frame, probe and earphone.This synchronous record principle of equipment utilization sound magnetic signal [3] carries out position determination of fault.During work, apply cycle impacting with high pressure by high direct voltage signal generator to cable and cause trouble spot to discharge, and generate field signal completely at cable, produce the acoustical signal outwards propagated centered by trouble spot simultaneously.Be positioned at earth's surface fixed point apparatus probe triggered by field signal after synchronously receive magnetic, acoustical signal.Because magnetic, acoustic signal propagation speed difference are obvious, there is the time difference in 2 kinds of signals that probe receives.Pop one's head in from fault more away from, the time difference is larger; Pop one's head in from fault more close to, the time difference is less; When probe is positioned at directly over fault, the time difference is minimum.According to this phenomenon, by intercepting discharging sound earphone and the observation of display waveform, mobile probe detects repeatedly, can find the accurate location of trouble spot.Sound magnetic-synchro fixed point principle as shown in Figure 5.In figure, dotted-line ellipse represents field signal, and semicircle solid line represents voice signal, and probe is integrated with magnetic, acoustic signal sensor, detects for fault-signal.

1.7 insulation measurement modules

Primarily of megohmmeter and ohmmeter composition.Wherein, megohmmeter is provided with 500V, 1000V, 2500V and 5000V and measures gear, there is startup self-detection and self-correcting function, during measurement, megohmmeter starts timing by built-in timer, timing will show the measurement result of insulation resistance after arriving setting-up time on 1# industrial computer interface with digital quantity or simulated pointer mode, automatically stop the output of measuring voltage simultaneously.

Ohmmeter have employed ADAM-4017 multichannel analog amount acquisition module and realizes resistance measurement function.During measurement, by measurand and known precision resistance resitstance voltage divider in series, voltage divider one termination+12V reference voltage source, other end ground connection, be digital quantity by 16 A/D sample conversion after the output access ADAM-4017 of voltage divider, then 1# industrial computer is uploaded to by RS485 interface, by 1# industrial computer according to formula

$R_1=R_0\frac{D_{\mathrm{FULL}}-D_0}{D_0}---\left(12\right)$

Calculate measured resistance value.In formula, R1 is measured resistance, and R0 is known resistance, and DFULL is the Full-span output value of A/D, and D0 is the A/D conversion value of resitstance voltage divider output voltage.The principle of work of ohmmeter as shown in Figure 6.

2, the Software for Design of system

2.1 operational module software configuration and communications protocol

The software of operational module is divided into series resonance voltage-withstand test, insulation measurement and fault localization 3 functional units.All unit subroutines are performed by master routine unified call, complete that test parameter is arranged, test mode is selected, the transmission of test command and various data and the task such as data processing and display.The general structure of system software as shown in Figure 7.

2.2 series resonance voltage-withstand tests

First suitable trial voltage and test period are set according to the electric pressure of cable, then select manually or automatic boosting pattern.

Module has 3 kinds of optional working methods:

1) when selecting automatic mode, module automatically adjusts the frequency of output voltage from 25Hz to 300Hz, search for resonance frequency simultaneously, after finding tuning-points, module automatic boosting, to the trial voltage value arranged, starts timer simultaneously, after test period arrives, module is depressurized to zero automatically, cuts off boosting ring current, and shows " experiment terminates ".

2) when selecting hands-off tuning/manual voltage boosting pattern, module hands-off tuning also searches for tuning-points, after finding tuning-points, click " high voltage rise " key, trial voltage can be risen to the trial voltage value of setting, start timer simultaneously, after test period arrives, module is depressurized to zero automatically, cuts off boosting ring current, and shows " experiment terminates ".

3) when selecting manual tuning/manual voltage boosting pattern, first manually " frequency liter " or " frequency is fallen " button is clicked, module is according to the step pitch regulation output frequency of ± 0.1Hz, if continue the click time more than 2 seconds, module is according to the step pitch regulation output frequency of ± 0.5Hz.By searching within the scope of 25-300Hz continuously, find resonant frequency point.Then click " high voltage rise " key, trial voltage can be risen to the trial voltage value of setting, start timer simultaneously.Finally after test period arrives, module is depressurized to zero automatically, cuts off boosting ring current, and shows " experiment terminates ".

2.3 cable fault localization

First action of low-voltage pulse, pulse current or second pulse test mode is selected, then fault localization scope is selected, there is 500m, 1km, 2km, 4km, 8km and 16km totally 6 kinds respectively, the value of wave speed of seletion calculation fault distance (refers to formula 9, default value is 172m/ μ s), arrange the signal gain of fault localization module, last hit testing button, software is delivered to fault localization functional module by communications protocol test command and tests.Record examination Wave data and pass industrial computer back by communications protocol, calculate fault distance and display waveform by software.

In addition, fault localization waveform and test parameter thereof can click " storage " key stored in waveform archive database, as history test cases for subsequent analysis and reference.

2.4 insulation measurement

When ohmmeter is measured, first suitable trial voltage is determined according to the electric pressure of test cable, there are 500V, 1000V, 2500V, 5000V totally 4 grades of selections, then select automatically or manual mode determination measured resistance value scope and test period, finally start test.When after arrival test period, module automatically calculates and shows the information such as insulation resistance, absorptance and polarization index.

When ohmmeter is measured, directly click " test " button, module measures the resistance value of tested cable loop automatically, and measurement result is presented on screen.

2.5 cable fault emulation range findings and typical case wave form analysis

The object of native system configuration 2# industrial computer is mainly in order to carry out the analysis of fault simulation range finding and actual measurement typical fault waveform.During emulation, first Dynamic simulation fault localization software, then cable total length, the nature of trouble (being respectively open circuit, short circuit and high resistant) of three-phase heart yearn, parameter and the information such as value of wave speed and fault distance are set in software interface, then distance measuring method is set, there are action of low-voltage pulse, pulse current, second pulse 3 kinds of distance measuring methods optional respectively, finally click software interface " test " key, Software Create fault localization waveform.

Software adopts actual measurement fault reflected impulse data genaration simulated fault reflection configuration.First, gather actual measurement action of low-voltage pulse, pulse current and second pulse trouble spot reflection configuration respectively, intercept trouble spot reflected waveform data as standard form, recorded in a program.Then calculate zero reference value number of data points of non-faulting section between test lead to trouble spot according to the fault distance arranged in simulated conditions and signal sampling frequency, and null value data and the pointwise of reflection configuration template data are drawn.Last benefit after reflection configuration template draws null value data, forms a complete fault reflection configuration.

In addition, simulation software by 1# industrial computer actual measurement typical fault type waveforms stored in database, can also form fault test waveform archives.Meanwhile, this module has case waveform input function, can store a large amount of fault waveform, recalls at any time and analyzes for tester, carry out localization of fault training when needing, and can be used as the use of cable's fault locating skill examination system.

3, experiment test

Test on 23 phase 10kV crosslinked cables respectively.Wherein, I cable total length 230m, A phase is intact with B phase, and C phase is about 123m place at distance test lead and there is fault; II cable total length 157m, A phase is about 55m place at distance test lead, B phase is about 134m place at distance test lead and there is fault, and C phase is intact.First relatively measure each of 2 cables with the megohmmeter 5000V shelves of system, result is as shown in table 1.Article 2, the healthy phases insulation resistance of cable is infinitely great, and the fault resstance of I cable C phase is the A phase fault resistance of 1M Ω, II cable be 0, B phase fault resistance is 2.2M Ω.Then measure by the A phase of ohmmeter to II cable of system, record fault resstance and be about 800 Ω.Can find out according to measurement result, there is high resistive fault with the B phase of II cable in the C phase of I cable, and the A phase of II cable exists low resistance faults.

Table 1 insulating resistance of cable measurement result

With the C phase of II cable, series resonance voltage-withstand test is carried out to A, B phase of I cable.Electric capacity 0.283 μ F/km according to cable unit length estimates, the electric capacity of I cable total length is 0.065 μ F, the electric capacity of II cable total length is 0.044 μ F, and the reactor of series resonance voltage-withstand test block configuration is 100H, therefore, No. I can be estimated according to formula (5) and be respectively 62Hz and 76Hz with the resonance frequency of II cable.Trial voltage, pressure-resistant time and resonance frequency are as shown in table 2, and withstand voltage test is all passed through.

Table 2 cable series connection Resonance Voltage Withstand Test

Rated voltage/kV	Trial voltage/kV	Resonance frequency/Hz	Pressure-resistant time/min
				10 (I A phases)	17.4(2U0)	61.4	5
10 (I B phases)	17.4(2U0)	60.7	5
				10 (II C phases)	17.4(2U0)	75.7	5

Carry out Low Voltage Impulse Method range finding to II cable A phase, cablebreak speed is 172m/ μ s, obtains fault localization waveform as shown in Figure 8, and as can be seen from the figure, trouble spot reflected impulse is negative polarity, and explanation is low resistance faults.Carry out pulse current method range finding to II cable B phase, cablebreak speed is 172m/ μ s, obtains fault localization waveform as shown in Figure 9, as can be seen from the figure trouble spot breakdown after the process of repeatedly row wave reflection.The range measurement of Fig. 8 and Fig. 9 is respectively 54m and 136m, substantially conforms to physical fault distance, and illustrate that range measurement is correct, fault localization module meets the request for utilization of traveling wave fault location.

After above-mentioned test completes, path searching and position determination of fault test are carried out to II cable B phase.

Between cable phase ground, inject 1kHz sound signal with system AC low-tension signal generator, the frequency then selecting cable line tester Received signal strength is 1kHz, from wireline test end, search cable trace.Test result shows, receives clear and definite and strong 1kHz tracer signal above cable trace, the tracer signal remitted its fury when leaving cable trace, and does not receive signal after away from cable, and the cable trace locating function of illustrative system is effective.

Between cable phase ground, apply 10kV periodic impulse signal with system dc High-voltage Signal Generator, the signal period is about 5s.According to fault localization result, search to being about 134m place from test lead.Through repeatedly detecting, fixed point apparatus receives trouble spot electric discharge sound and waveform very soon, according to the delay characteristics receiving the cycle of voice signal, the repeatability of waveform and sound magnetic signal, determines the exact position of trouble spot.Position determination of fault result shows that the position determination of fault function of system is reliable.

Experimental result shows, each test event can be unified to carry out in same system, and convenient functional conversion is quick, meets the requirement of cable integration test training completely.

In sum, content of the present invention is not limited in the above-described embodiment, and those skilled in the art can propose other embodiment within technological guidance's thought of the present invention, but these embodiments all comprise within the scope of the present invention.

Claims (1)

1. a midium voltage cable electric test skills training system, is characterized in that: comprise

Operation control module, it is made up of the function switch/adjusting knob on industrial computer and control panel, for controlling and regulating other functional module work;

Major insulation voltage-withstand test module, adopts the resistance to die block of frequency modulation series resonance voltage-resisting test apparatus design cable major insulation, and uses series resonance principal to carry out dielectric voltage withstand test to cable;

High/low pressure signal generator module, comprises high direct voltage signal generator and AC low-tension signal generator, and this module can coordinate carries out cable fault localization, position determination of fault, cable discriminating/path searching;

Fault localization module, it comprises impulse method fault locator and electric-resistivity method fault locator, and impulse method fault locator is used for the range finding of Low Voltage Impulse Method, pulse current method and secondary pulse process, and electric-resistivity method fault locator is used for the fault localization of protective coverings of cable;

Cable discriminating/path searching module, its AC low-tension signal generator coordinate under can to charged/not live electric cable differentiate and path searching;

Position determination of fault module, it forms primarily of type cable failure positioning instrument, comprises main frame, probe and earphone, and the synchronous record principle of this module utilization sound magnetic signal carries out position determination of fault;

Insulation measurement module, primarily of megohmmeter and ohmmeter composition, wherein, megohmmeter is provided with 500V, 1000V, 2500V and 5000V and measures gear, have startup self-detection and self-correcting function, ohmmeter have employed ADAM-4017 multichannel analog amount acquisition module and realizes resistance measurement function.