1、 Overview:

The series of power cable fault testers are widely used inThe detection of low resistance, short circuit, open circuit, and various high resistance faults in aluminum core, copper core power cables, high-frequency coaxial cables, and local telephone cables with different cross-sections below 35KV is an essential equipment for ensuring safe power supply and a capable assistant for cable production and maintenance workers. Through actual use by hundreds of various units such as Beijing Power Supply Bureau, Tianjin Power Supply Bureau, Wuhan Power Supply Bureau, and Xi'an Power Supply Bureau, users have generally reported that cable fault testing instruments have the advantages of easy use, high measurement accuracy, short testing time, and stable performance, and have received unanimous praise from a large number of users.

2、 Instrument functions and features:

1．measurable35KVThe high and low resistance faults of all cables of the following levels are widely applicable.

2．Featuring user-friendly software and a fully Chinese menu. The button definition is simple and clear. The measurement method is simple and fast.

3．The success rate of fault detection, testing accuracy, and ease of testing are superior to any domestic testing equipment.

4．Super LargetouchAs a display terminal, the LCD screen,The instrument hasPowerful data processing capabilities and user-friendly display interface.

5．It has extremely safe sampling high-voltage protection measures. The testing instrument will not crash or be damaged in high-pressure environments.

6．No testing blind spots.

7．Built in power supply, capable of testing cable open circuit and low resistance short circuit faults in non powered environments.

3、 Main performance indicators:

1．Testing method:Low voltage pulse, high voltage flashover, speed measurement.

2Impact high pressure: below35KVPower cables.

3Data samplingfastrate：80MHz、40MHz、20MHz、10MHz.

4Test distance:＞30Km.

5Reading resolution:1m.

6System testing accuracy：less than50cm.

7．Test cable pulse widthProvided with:“0.05”The “0.1”The “0.2”The “0.5”The “1”The “2”The “8”Microseconds.

8Pulse transmissionsignalreachfaultAutomatic reflection of signalsDisplay,Causing malfunctioncharacteristic waveformThe representation is extremely simple.

9．Capable of storing test waveforms: It can conveniently store the waveforms tested on site in the instrument in the specified order for easy retrieval at any timeobserve.canStore a large amount of on-site test waveforms.

10Can detect the faults measuredPoint waveformSimultaneously display the full-length open circuit waveform of Good Phase on the screen for on-screen comparisonCompared with superposition, the fault distance can be automatically determined.

11Built in power supply: The instrument can work continuously after being fully charged3For hours or more, it can also work with an external AC power source.

12．working conditions：temperature-10℃～+45℃，relative humidity 90.

4、 System composition and working principle of the instrument:

Waveform recording analyzer (distance measuring host)

This part is the brain of the entire instrument, responsible for sending instructions to other components, coordinating the work of each component, and providing the operator with an interface for human-machine dialogue. Its main function is to perform high-speed sampling and recording of measurement pulses, and then perform high-speed computational analysis on the collected signals.

5、 Instrument panel description:

²Sampling method

Press the sampling method key to bring up a submenu. The submenu includesThe 5 options are low-voltage pulse/flashover method/three pulse/eight pulse/speed measurement. The instrument defaults to low-voltage pulse, and the corresponding sampling method can be selected according to the measurement needs. Press the 'Sampling Method' button again to exit this function.

²pulse width

This menu is invalid in high-voltage flashover testing method. Press the pulse width key to bring up the pulse width selection submenu. You can select the appropriate pulse width based on the test distance and press the corresponding submenu key to choose the pulse width. The pulse width size is50 nanoseconds, 100 nanoseconds, 200 nanoseconds, 1 microsecond, 2 microseconds, 5 microseconds, 8 microsecondscommon7A gear. When selectedWhen the pulse width is 50 nanoseconds, the computer automatically locks the reading accuracy to 1 meter; When selected for 8 microseconds, the computer automatically locks the reading accuracy to 8 meters; When selecting other pulse widths, you can adjust them arbitrarily by pressing the reading accuracy key, and the initial value of the instrument is 200 nanoseconds. Press the 'Pulse Width Key' again to exit this function.

²Cable Type

The propagation speed of radio waves varies in cables with different media, so the media type must be selected before testing faults to determine the propagation speed of radio waves. Press the cable type button, and the screen will display a dialogue box for selecting cable types, including oil immersed paper type, non dripping oil type, cross-linked ethylene, polyvinyl chloride, and unknown types5 options, the initial value of the instrument isOil immersed paper typeYou can press the corresponding cable type key as needed. If the tested cable does not belong to the four known types, it should be tested according toUnknown type key "pops up a dialog box, adjust the wave velocity value, and press the" OK "key when the selected value is reached. Press the 'Cable Type' key again to exit this function.Maximum waveform speed300m/us

²Reading accuracy

Select the appropriate gear according to the measurement requirements. Divided intoThe measurement accuracy is 8 meters/4 meters/2 meters/1 meter, and the initial value of the instrument is 2 meters. Press again“Reading accuracy”Exit this feature.

²Waveform scaling

Due to the large amount of waveform data, local waveforms are displayed on the screen after each sampling. In order to observe waveform details, it is necessary to scale the waveform. press“Waveform zoom key”Enter the zoom function, provided by the instrumentThree compression ratios, namely1. 1/2, 1/3，pass through“Left click《 perhaps right button 》”Can perform waveform analysisCycle with 3 different proportionsCompression.The compression ratio can be observed through the bottom right corner of the screen. Press again“Waveform zoom key”，Exit this feature.

²Rolling screen display

After waveform expansion, it needs to be divided into multiple segments for display, and the instrument automatically displays the first segment. If it is necessary to observe the waveform of each subsequent segment, it should be executedRoll screen function. Press the 'scroll display button' to access the screen“Left click《 perhaps right button 》”The waveform can be moved left and right. Press the 'scroll display button' again to exit this function.

²Save waveform

Store the displayed content on the screen in the instrument,Can store20 waveforms.

²Retrieve waveform

Reproduce the stored waveform on the screen.

²Total length of cable

existIf "Speed Measurement" is executed in the "Sampling Method" submenu, the cable type in the menu will change to the full length of the cable. Press the 'Full Length' button to bring up the 'Cable Length' input dialog box on the screen, with an initial value of '0' meters. After entering the cable length value, press the "OK" button.

²delayed

Set trigger time, which is generally not necessary.

²positioning

Used to determine the starting point of the measurement. executeAfter pressing the "locate" button, the current position of the cursor is determined as the starting point for testing. By“Left click《 perhaps right button 》”The cursor can be moved left and right.

²Automatic distance detection

pressAutomatic distance detection button ", cursor for automatic positioning, automatic display of fault distance in the upper left corner of the screen.

²left key/Right click (add/subtract)

When moving the cursor for positioning, each press“Left click《 perhaps right button 》”Once, move the vernier ruler left/right by oneSingle Site(pixels); When continuously pressing the cursor to the left/When right clicking, the cursor moves faster,Move eight unit points at once.

When selecting waveform scaling, scrolling display, or waveform shifting, pressLeft click《 perhaps right button 》(Add/subtract).

²Sampling key

When the instrument is in low voltage pulse measurement mode, pressing the sampling button will immediately display the emission pulse and echo pulse in the waveform display area of the screen. The red waveform is the local waveform, and the blue waveform isoverall situationWaveform.

When the instrument is in the high-voltage flashover measurement mode, after pressing the sampling button, when there is an external trigger, the screen will display the high-voltage flashover wave. The red waveform is the local waveform, and the blue waveform is the global waveform.

Due to the fact that this instrument mainly operates in high voltage environments, before using this instrument to detect cable faults on site, it is necessary to carefully read the relevant instrument testing principles, wiring methods, and usage precautions in this user manual. To avoid personal accidents and damage to instruments and equipment.

1．Testing low resistance grounding, short circuit, and open circuit faults of cables using low-voltage pulse method

A．Connect a clamp wire directly to the input/output interface of the cable fault tester. Clamp the red clip of the clamp wire onto the faulty core wire of the cable, and clamp the black clip onto the outer ground wire of the cable.

B．Turn on the power switch of the instrument, and once the screen is working, touch anywhere on the screen to enter the settings interfaceAt this time, the default state of the instrument isLow voltage pulse method. The selection of usage method should be based on the type, length, and preliminary judgment of the fault nature of the tested cable on site. Set inWhen using the "low voltage pulse method", you can also perform wave velocity measurement and open historical files to view previous test results on this interface.

C. After completing the device parameter settings, click the "Sampling" button, and the instrument will automatically emit test pulsesThis interface will display the open circuit (full length) waveform or low resistance ground (short circuit) fault waveform of the cable. If the waveform is not good, the operator should adjust itObserve the "median" and "amplitude" of the collected echoes until the operator deems that the amplitude and position of the echoes are suitable for analysis and positioning.

D. Wave positioning reading distance.Low voltage pulse distance detection is relatively easy, as long as the cursor is positioned at the starting points of the transmitted and reflected waves.

VIPrecautions for instrument use:

1Before conducting fault testing, carefully read the instrument manual, master the operating steps, and ensure safe wiring of the instrument.

2One of the main features of this cable fault pre positioning test host is that there is no external power supply, and all equipment is provided by the built-in battery. This brings great convenience to the use of the instrument and improves safety factors. The status of the internal power battery is displayed as a percentage of battery level in the upper right corner of the screen. When insufficient(about10%When)There will be sound prompts. When testing cable faults on site, the battery voltage of the distance measuring host must be sufficient. After the battery voltage is sufficient, it can ensure normal operation2More than hours. The instrument can be connected to an AC power source for float charging during use. However, during high-voltage flashover testing, it is necessary to completely disconnect from the external AC power supply.

3Instruments are highly precise electronic devices. Non professionals should never dismantle it lightly. If there is a problem with the instrument, please contact the dealer or our company in a timely manner. If the instrument is damaged due to human factors, you will lose the right to warranty the instrument.

4.Users should carefully read the user manual, have knowledge of equipment operation, and receive training on the use of this instrument. High voltage protection measures should be taken during use, and equipment should be regularly inspected3Charge once a month for testing and maintenance.

7Testing operation skills:

Although the waveform of low-voltage pulse testing is easy to judge and has high accuracy, it is necessary to master certain skills in order to obtain an ideal and easy to read waveform.

1Select the "pulse width" according to the distance of the fault caused by the length of the cable. For long-distance faults, due to weak echoes, the inflection point of the echo front changes slowly, making it difficult to determine the starting point of the fault echo. In this case, it is necessary to adjust the pulse width.

2When in general use, the cable length is less than500Rice selection0.2us.The cable length is greater than500Rice selection2us.The cable length is greater than2000Rice selection8us.

3For short distance cable faults, the fault echo is very close to the transmitted test pulse. At this time, it is necessary to go to the other end of the cable for testing in order to read the fault distance.

4Waveform analysis techniques:

Although the basic rules of the instrument have been mastered from the above introduction, it is still necessary to improve the accurate judgment ability of the fault point distance through the specific analysis of the on-site measured waveforms in the following parts:

8、 Instrument compatibility:

1. One cable fault pre positioning test host (distance measuring host)

2. One signal sampling line

3. One current sampler

4. One charger

5. One user manual for the instrument