Low Voltage Hidden Cable Fault Locator For Detecting Earth Leakage Broken Core

Product Specification

Payment Terms	T/T	Supply Ability	500units/month
Delivery Time	5-8 work days	Packaging Details	Wooden cases
Transmitter	Output power: pulse power greater than 2.5W (when the high-range load resistance is 80KΩ)	Signal receiver	Width 0.20.1mS, intermittent period 1.81S
Brand Name	XZH TEST	Model Number	XHHD530M
Certification	CE	Place of Origin	Xi'an, Shaanxi, China
High Light	Low Voltage Cable Fault Locator ，Hidden Cable Fault Locator

The hidden line buried line fault detector XHHD530M is a special instrument for power, broadcasting, post and telecommunications departments, as well as industrial and mining, rural areas to find underground cables, including direct buried armored cable lines and buried line faults.

 

It can detect the direction of the buried line, the more accurate underground position, the basic buried depth, and various ground leakage faults, broken core faults, including lines under paddy fields, cement roads, bricks and stones, asphalt roads, and lines in the walls of buildings. Waterproof wires and cables used on the ground can be detected by using this instrument through appropriate methods.

 

The fault locator consists of a signal transmitter, a signal receiver, a probe, a plug and other parts. The transmitter and receiver are small in size, reasonable in structure, and beautiful in appearance.

 

The instrument has the advantages of high sensitivity, strong anti-interference ability of the sound meter synchronization, convenient operation and carrying, and rapid and accurate location of fault points. The receiver and sound meter are synchronized, with high and low sensitivity settings. The transmitter is equipped with output indication and measurement KΩ function, which can replace the multimeter or megohmmeter to check the circuit's continuity, disconnection, and mixing, measure the size of the ground leakage resistance, and directly determine the nature of the fault. The transmitter adds an output terminal "Output 2", which broadens the detection methods and functions.

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Technical performance

Transmitter

The transmitter panel is equipped with "power switch", "power indication"; "output selection", "high, medium, low"; "output indication" and "K measurement" switching switches, and the indicator light indicates the switching position; "output·KΩ measurement" shares an output terminal, which is switched by the "output·indication" and "KΩ measurement" switches; set "output 2" output terminal; square meter head indicates output and KΩ resistance. It can check the line on, off, mixed, and measure the size of the ground leakage resistance.
Output signal form	pulse period 1.34±0.15mS. Width 0.2 ±0.1mS intermittent period 1.8±1S.
Output voltage	pulse period Upp high range greater than 1000V, medium range greater than 60V, low range greater than 30V.
KΩ measurement	It can check the side line on, off, mixed and leakage group size, and determine the nature of the fault.
The "output 2" output terminal	It can output peak pulse short-circuit current 1-5A.
Output power	Pulse power greater than 2.5W (when high-end load resistance is 80KΩ).
Power supply	8.4V.

 

Receiver

Set power switch, power indicator, "high gear", "low gear" switch; when there is a signal on the meter, it indicates the positive direction or negative direction; there is an input terminal on the upper side, which can be inserted into the probe or plug-in plug respectively.
Received signal form	pulse period 1.360.15mS
	width 0.20.1mS, intermittent period 1.81S.
Power supply	6V (4 No. 5 batteries)
Detection fault range and detection accuracy	When the detection length is 3km, the burial depth is 2m short circuit to the ground, and the leakage resistance of the leakage fault is less than 500kΩ, the insertion measurement positioning error is less than 0.2m.
	When detecting a broken core fault with a length of 1km and a burial depth of 2m and good insulation to the ground, the inspection positioning error is less than 0.4m.
	The actual detection length can exceed 1-5km and the burial depth is 2-3m.
Anti-interference performance	The received signal is clear and can detect underground wire faults under 220 kV lines.
Instrument working conditions	This instrument can work continuously in an environment with an ambient temperature of -15 and an atmospheric pressure of 86-108Kpa.

 

 

Instrument principle and structure
This instrument consists of a transmitter, a receiver, a probe and a head, a pair of plugs and plugs, connecting wires, etc.

 

Transmitter

(1) Mainly outputs continuous pulse signals, which is the signal source for finding faults.

(2) kΩ function, can detect the continuity, disconnection, mixing and leakage resistance of the line, and determine the nature and type of fault.

(3) "Output 2" output terminal outputs large current

 

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Packing list

Item	Name	Qty.
1	Transmitter	1
2	Receiver	1
3	Probe	1
4	Probe head	1
5	Insert rod(red black)	2
6	Connection lines	2
7	Charger	1

 

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Detection method and principle
I. Induction method
According to the principle of electromagnetic field, after a pulse signal is sent to the line, there is a magnetic field in the space around the line. The induction method is to use the probe to induction and receive the spatial magnetic field signal, which is amplified by the receiver. It becomes sound and makes the needle swing. By listening to the size of the speaker sound and observing the swing amplitude of the needle, the direction of the buried line, the large range of the fault point, the accurate location of the buried line and the basic burial depth can be determined.

 

II. Insertion method
According to the principle that after a pulse signal is sent to the buried line, a regular electric field related to the nature of the fault will be formed on the ground surface above the buried route and the fault point. The insertion method is to use two plugs to pick up the point difference between the two points in the distributed electric field, which is amplified by the receiver to become the needle swing and sound. By observing the size and direction of the needle swing and the size of the sound, the underground position of the buried line and the accurate location of the fault point can be accurately determined.
Instructions for use

1. Inspection before using the instrument
1.1.1 Transmitter: Set the power switch to the "on" position. The transmitter power indicator light should heat up and a faint intermittent oscillation sound should be heard. The input selection switch can be set to high, medium, and low. The function selection switch "measurement selection" is set to "output prompt". You can see that the needle swings with the output. If it is set to "KΩ measurement", the needle of the short-circuited output terminal should point to (KΩ) zero, which means that the transmitter is working normally. You can send a signal to the line or measure KΩ to check the fault type of the line.

The transmitter has an additional "Output 2" output terminal, which can give an intermittent peak pulse current of 1-5A. It is specially used to detect metallic short-circuit faults. When using it, the pull switch at the lower left should be pulled to the right, that is, the side where the output indicator light is on, to obtain an intermittent pulse large current to improve the effect and reduce power consumption.

 

1.1.2 Receiver: Open the battery cover on the back and install the No. 5 battery. Note that the positive and negative poles of the battery cannot be connected incorrectly. Then turn the power switch to the "on" position. The power indicator should light up, indicating that the power is on. Turn the function switch to the "high" position. You can hear a slight static noise from the unit, indicating that the receiver is normal. At this time, insert the probe plug into the receiver and bring the probe close to the receiver speaker. You can hear the self-excited whistle from the receiver, indicating that the probe is intact and the receiver is working properly. Otherwise, check whether the probe and plug are disconnected or mixed.

 

2. Determine the nature and type of the fault
2.2.1 First, the fault line, the lead-in and lead-out ends, including the branch load, electric meter and other electrical circuits connected to the fault line should be separated, and then the power should be cut off and separated, and the KΩ measurement of the fault line should be performed. During the measurement, the two lead-out ends of the buried line should be suspended separately, and they cannot touch each other or be grounded.

 

In this case, KΩ measurement is performed on each wire at one lead-out end, and the resistance value of each wire to the ground is recorded to find the accurate grounding resistance of the fault line to determine the nature and type of the fault of the fault line. If necessary, the same test should be performed on the lead-out end of the other end.

 

Find the one with the smallest grounding resistance and send the test signal. This process is also a test to see if the transmitter is working normally.

 

During operation, install the transmitter battery, turn on the transmitter, the power indicator light is on, put the two red and black wiring forks in, turn the lower left toggle switch to the left, so that the KΩ measurement indicator light is on, then clamp the two black and red wire fish clips together, and watch the needle on the transmitter should point to 0, and separate the two fish clips. The needle should return to the infinite ∞ position. At this time, the black fish clip can be connected to the ground, and the red fish clip can be connected to each line respectively. Measure and record the insulation resistance value of each line to the ground to determine the nature and type of the fault. At this time, the red and black fish clips connected to the transmitter become the two test leads of the multimeter.

 

Because the detection method is different for different types of faults, it is necessary to first clarify the nature and type of the fault. Then turn the switch to the "output indication" position, and according to the leakage size, turn the output selection switch to the "high. medium. low" configuration and position. At this time, the transmitter has sent a detection signal to the line.

 

2.2.2 Leakage grounding fault: Most of the faults of underground lines are caused by leakage due to damage to the insulation layer, or corrosion and burning that prevents power transmission. This type of leakage includes: continuous core high, broken core high, low resistance grounding faults, line short circuit high and low resistance grounding faults, and approximately metallic grounding faults with large-scale damage to the insulation layer. According to the needs of the detection method, all grounding faults are divided into sections according to the size of the grounding resistance. The grounding resistance of about 20kΩ and below is called low resistance grounding, and the grounding resistance between 20-500kΩ is called high resistance grounding.

 

2.2.3 Broken core fault with good insulation: This type of fault is just a broken core that cannot transmit power, and the grounding resistance is above MΩ.

 

3. Use induction to detect the direction of the buried ground, the more accurate position, the basic buried depth and various faults
3.31 Operation method: According to the methods of 1.1.1 and 1.1.2, the transmitter and receiver work normally.

The black terminal of the transmitter output end is grounded with a connecting wire.

The grounding should be good and do not connect other grounding wires.

The red wire is buried or the fault line.

The "output selection" can be selected according to the nature of the fault.

 

If you only measure the direction of the buried ground line, the output selection can be set to medium or high.

At this time, the transmitter has sent a pulse test signal to the buried line.

 

Set the "function switch" of the receiver to "high" and bring the probe close to the transmitter or buried line.

The receiver speaker will emit intermittent "beep-beep-beep" sounds.

Changing the relative position or distance between the probe and the buried line will change the sound of the receiver.

The position with the loudest sound is when the probe is horizontally (i.e., the axial direction of the probe) directly above the direction of the buried line. In this way, walking in the direction of the loudest sound is the direction of the buried line. See the experience section for measuring the accurate underground position and basic buried depth.

 

3.3.2 Detection of low-resistance grounding fault: (including broken core low-resistance grounding)
According to the method described in 3.3.1, the transmitter is set to low-speed output, and detection starts from the signal transmission end.

 

During the detection process, the sound volume is basically unchanged at first.

When the sound is significantly reduced at a certain point, the reduced signal can still be heard after walking 3-5m forward. Then the low-resistance grounding fault point is about 0.3-0.5m back from the place where the sound is significantly reduced. This method is also applicable to the detection of broken core grounding faults. See Figures 2 and 3.

 

3.3.3 Detection of broken core faults with good insulation:
The method is basically the same as 3.3.2. The signal of this type of fault is weak, and the transmitter "output selection" should be set to medium or high.

 

In order to be more accurate, the "two-time positioning method" can be used, that is, according to the method in 3.3.1, first send a signal from a section of the buried line to measure the sound reduction, and then place a mark at a place where the sound is basically inaudible after 3 to 5 meters.

Then send a signal from the other end of the faulty buried line, and also measure a place where the sound is basically inaudible after 3 to 5 meters.

Then place a mark below the "middle" point of the line connecting the two marks.

 

This "two-time positioning method" is also applicable to low-resistance grounding and broken-core low-resistance grounding faults.

 

However, it must be noted that the "two-time positioning method" is not applicable to two faults in one line. If there are two faults, one should be solved first.

 

3.3.4 Broken core detection of waterproof wire and wall line:
The method is the same as 3.3.1 and 3.3.2, but the difference is that the probe has the opportunity to approach the line, about 0.3 meters.

 

At this time, not only the sound increases, but also the needle can swing. In this way, when the needle swing amplitude is significantly reduced, it is 0.1 to 0.2 meters back to the fault point.

 

The waterproof line can be placed flat on the ground. Connect the black terminal to the ground, and the red terminal to the fault line.

 

3.3.5 Short-circuit fault of waterproof wire and wall line:
The detection method is the same as 3.3.3, but the black terminal of the transmitter output cannot be grounded, but the red and black terminals are connected to the two short-circuited wires respectively. When the sound and the needle swing suddenly increase at a certain place, then this place is the fault point. Note that this method is in a short-circuit working state for the transmitter output, and the battery consumption is very large, so it is not suitable for long-term operation. The transmitter is set to low-speed output, or use the "Output 2" output terminal.

 

4. Use the insertion method to measure the accurate path, direction and accurate fault point of the underground line of various faults.
According to methods 1.1.1 and 1.1.2, make the generator and receiver work normally, the black terminal of the transmitter output end is grounded, the grounding should be good, and the grounding point should be in the opposite direction of the underground line and in line with the direction of the underground line. If the fault point is close to the signal input end, the distance from the location to the fault line should be greater than 5 to 10 meters.

 

The red terminal is grounded to the buried line or the fault line, and the "output selection" is set to "low gear". At this time, the transmitter sends a signal to the buried wire, the receiver's "function switch" is set to "high", and the plugs of the two plugs are inserted into the receiver input jack (the probe and the plug share a socket. At this time, hold the receiver in one hand and the red and black plastic handles of the two sticks in the other hand, and bring the red and black tips close to the transmitter respectively. Hold the red and black plastic handles of the two sticks in the other hand, and pull the red and black tips apart by about 0.5 meters. Insert them into the ground near the buried wire, and you will hear intermittent beeps from the sounder. At the same time, observe that the needle of the receiver should swing intermittently. Otherwise, check the connection of the two sticks and whether the plugs are broken or mixed. If it is normal, pull the tips of the two plugs. Open a certain distance, the distance can be selected from 0.1 to 0.5 meters. After the two sticks are inserted into the ground, the needle swing range is preferably one to five grids. Insert the two sticks vertically into the ground in the direction of the buried line, keep the red stick in front and the black stick in the back, and observe the direction of the needle. If it swings to the "+" direction, move the two sticks in the direction of the red stick. If it swings to the "+" direction, move the two sticks in the direction of the black stick. Move until the sound is the smallest and the needle basically does not move. At this time, the "middle" point of the line between the two stick insertion points is the accurate underground position of the buried line.

 

This method is called (I) the "lateral symmetry method".

 

Check Figure 4 to see if (II) the "lateral symmetry method" should be used. The method is: insert a rod into the fixed "middle" point and keep it still, and insert the other rod into two points of the fixed "middle" point of the fault twice. Through the two insertions, observe that the direction and size of the needle swing should be consistent, and the sound size should also be consistent, which proves that it is the accurate "middle" point. Use the "horizontal symmetry method" to insert and measure once every 3 to 10 meters along the general direction of the buried line. You can find several "middle" points. The line connecting these "middle" points is the more accurate path, position, and direction of the buried line. It can also be used. Use (three) "forward symmetry method" to insert and measure, that is, insert two rods into the ground directly above the buried line along the direction of the buried line. The red rod is in Put the black stick in first and then the black stick in the back, and then insert the sticks along the line for measurement with the same stick spacing (I): "Horizontal symmetry method". Note that when the sound increases but the needle swing decreases, the stick spacing should be reduced or the low sensitivity gear should be changed, that is, the "function switch" of the receiver should be set to "low gear". In this way, when the needle points to "ten" but not to "one", it means that the fault point has been passed. The two sticks should be moved back a small distance carefully, or one stick should be fixed and the other stick should be moved to reduce or increase the distance between the two insertion points until the sound is the smallest and the needle basically does not move. In this way, the fault point is below the "middle" point of the line connecting the two stick insertion points. This method is referred to as (III) "forward symmetry method".

 

The accuracy should be verified by

(iv) "forward symmetry verification method", which is the same as the "transverse symmetry verification method". In order to be more accurate, the "transverse symmetry method" can be used to interpolate at the "middle" point. In this way, the two "middle" points measured in the horizontal and forward directions basically coincide with each other, which is a more accurate fault point. This method is referred to as (v) "cross intersection method".

 

Whether the fault point is accurate or not, and in order to exclude false points, it can be verified by the following method: insert a rod into the measured fault point and fix it, and use another rod to do circular interpolation around the fixed rod at equal distances (select about 0.1-0.3m). Observe that the swing direction of the needle should be consistent and the swing amplitude should be basically the same. Then the insertion point of the fixed rod is the fault point. This method is referred to as

(vi) "equipotential circle verification method".

 

The second verification method is: 2-3m in front of the initially determined fault point (forward), insert the red stick and keep it still, insert the black stick twice on the left and right sides of the red stick, no matter on the left or right side, the stick distance is selected from 0.5-1.5m, and keep moving the black stick until the sound is the smallest and the needle is basically motionless. In this way, the two insertion points of the black stick are obtained by two insertion tests. The two insertion points and the red point insertion points are connected by lines. Some of the two connecting lines go to the two "middle" points. The intersection of the vertical lines of the two "middle" points is the fault point. For the convenience of description, this method is referred to as (VII) "X-type verification method".

 

This method is basically the same as (VIII) "long-distance insertion method". Some fault points are far away from the signal sending end, more than 60m, in the middle section, the signal is very weak and easy to be lost when inserting directly above. In order not to lose the signal, To save time, you can use

(9) "lateral one-side method", that is, insert two rods horizontally on either side of the line, and walk along the line direction

 

(10) "equidistant comparison". When you find that the sound and the needle swing amplitude are significantly reduced, it means that you have passed the fault point.

 

Use (11) "one-side angle method", that is, insert two rods in the forward direction on either side of the line, the red rod first and the black rod later, and keep the line between the red and black rod insertion points at an angle of about 30 degrees with the direction of the buried line. That is, the red rod is 0.3 to 1 meter away from the direction of the buried line, and the black rod is 0.6 to 1.5 meters away. Insert and measure along the line. When you find that the sound is reduced and the needle basically does not move, it means that you have reached the fault point. Then walk forward and the needle points from the original "10" to "1", indicating the fault point. The above (9) and (10) methods can quickly find the fault point area, and then use (1) to (6) methods to accurately locate it.

 

Because the signal is strong at the fault point, the (12) "short distance method" can be used at this point, that is, take a rod distance of about 0.1 meters and insert it horizontally and forward to determine the fault point.

 

There is also (13) the "two comparison method", that is, insert it along the line direction on one side of the line, fix one rod and keep moving the other rod until the sound is the smallest. The connection direction of the two insertion points is the direction of the buried line (this is not applicable at T-joint corners and uneven sections, as well as close to the signal end and the fault point).

 

(15) "Humidification method", when there is a cement floor, a brick floor or low temperature in winter, it is difficult to insert the tip of the rod into the ground. You can use items with a large water content, such as towels, cloth, etc., wrap the end of the rod thickly, tie it tightly and soak it in water, and heat it appropriately in winter to prevent freezing. You can also water the insertion point along the line to increase the contact surface.

 

Due to the complex electromagnetic field reflected by the buried wire on the ground, coupled with factors such as line structure, terrain, ground objects, and other electromagnetic field interference, there will be different degrees of "false images" and "false points". For example, in these areas: in the lead-out section, lead-out joint, protruding joint, coiled joint, T-joint, corner of the buried wire, as well as crossing underground lines and metal pipes, the depth of burial is not on the same plane, etc., there are reverse needles and even meet the "cross intersection method". As long as the nature and type of the fault are understood, the above-mentioned dozen detection methods, especially the verification method, can be carefully used to eliminate the "false points" and accurately determine the fault point. That is to say, the fault point found must be verified according to the nature and type of the fault with the corresponding verification method to eliminate the false points. All ground leakage faults are verified by the "equipotential circle verification method".

1.1 The continuous core high-resistance grounding fault should be because this type of fault signal is weak and the "capacitive current" is strong, resulting in a small fault area and easy leakage. Therefore, it is necessary to carefully insert and test without missing a part, and the transmitter output uses a medium-to-high-end small rod distance.

 

4.2 Broken core fault with good insulation: This type of fault is very special. When the transmitter output is set to high, the signal is also weak, basically pure capacitive current.

 

When the gear is directly above the line and plugged in for measurement. When the red stick is in front within 10 to 15 meters of the signal end, the strength of the "positive" direction of the meter needle swing gradually decreases from the signal end.

 

After 15 meters, the direction is uncertain. Only when it is 3 to 5 meters close to the fault point, the meter needle starts to swing in a fixed direction. Note that from 5 meters before the fault point to the fault point, when the red stick is in front, the meter swings in one direction. 1 to 1.5 meters after the fault point, the sound and the meter swing amplitude decrease very quickly. This is a significant feature of this type of fault.

 

In order to save time, when encountering this type of fault, you can first use the induction method to measure a large range or use (16) the "lateral one-side method", that is, starting from the signal sending end, horizontally insert the test on either side of the buried line, select a rod spacing of 0.3 to 0.5 meters, and insert it every 1 to 2 meters. As long as the sound and the needle swing amplitude do not change significantly during the insertion test, insert the test forward until the sound and the needle swing amplitude decrease very quickly, that is, reach or pass the fault point, and then use the "lateral symmetry method" to determine the position of the buried line, and then insert the test in the forward direction, select the rod spacing of about 0.3 meters, and perform (10) "equidistant comparison". The fault point is below the "middle" point where the two rods with the largest sound and needle swing amplitude are connected. See Figure 6. Use (17) the "X-type verification method" for verification.

In addition, there are "short-circuit grounding method", "right-angle turn method" and "solar radiation method". See "Practical Buried Line Fault Detection Technology"

 

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Company profile

 

XZH TEST is a professional cable fault detection equipment manufacturer. We are a young team. Our development philosophy is humanized management, intelligent cloud-based products, and internationalized operations. Our development mission is to make electrical equipment free from undetectable failures.

Since its inception in 2013, our company has grown to become one of the largest manufacturer of underground cable fault detection equipment in China. An ISO 9001 and CE certified company, we produces a broad range of testing equipment.

 

What we can do

We have the ability to innovate new products and technologies.

We can provide complete system solutions for your project.

We provide online and offline practical and theoretical training.

We provide instrument repair and calibration.

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FAQ

 

1. Are you a trading company or a manufacturer?
We are a professional manufacturer with more than 10 years of experience. We can strictly control the quality of parts and finished products.

 

2. What is the delivery time and inventory?
If our best-selling products are in stock, it will be 5-8 working days for shipment. But for mass production and customized production, the time will take 2-4 weeks.

 

3. What are your payment terms?
Payment ≤ USD 2000, 100% T/T prepayment. Orders over USD 2000 can be negotiated.

 

4. How long is your product warranty?
We provide 1 year warranty for the equipment.

 

5. How do you ensure quality?
The product links include R&D, manufacturing, commissioning and technical support, following strict and scientific management principles. Therefore, we can support strong production and R&D capabilities, and can produce high-quality products at competitive prices to meet customers' high requirements.

 

6. What support can I get?
We will provide training support, marketing support, technical support and supply chain support. You can contact us for more information.

 

7. Where is your factory? Can I visit your factory?
We are located in Xi'an, Shaanxi, China. We are close to Xi'an Xianyang International Airport, which is about 2 and half hours by plane from Shanghai and Guangzhou. All customers from all over the world are welcome to visit us.

 

8. How to become your dealer?
Every company interested in power system instruments can contact us without hesitation, including website letters, emails, telephones, etc. We will contact you quickly according to your company information and cooperation intentions.