Cable Fault Pinpointer

XHDD503E

The cable fault pinpoint locator XHDD503E uses the principles of vibration pickup and electromagnetic induction to determine the specific location of the cable fault point. A high-voltage pulse generator is used to cause flash over discharge at the fault point. Physical phenomena such as vibration waves, sound waves, and electromagnetic waves generated by the flash over discharge at the fault point are picked up by a special probe of the pointing instrument, amplified, processed, displayed, and output by the cable fault pointing instrument. The precise location of the fault point is determined by the tester's hearing and vision. That is, the task of accurately locating the cable fault point "directly above the cable and within the range of rough measurement" is completed.

This cable fault pinpointer is suitable for low-resistance, short-circuit, open-circuit and disconnection faults of power cables, high-frequency coaxial cables, street light cables, and buried wires made of various materials with different cross-sections and media, as well as high-resistance leakage and high-resistance flash over fault.

Product features

1. 5-inch touch-high brightness LCD ensures visibility under sunlight.

2. It has 4 test modes: standard, enhanced, noise reduction, and customized.

3. It has 4 positioning functions: acoustic-magnetic synchronization, pure acoustic, pure magnetic, and step voltage.

4. It has background noise reduction technology and can choose from a variety of filtering methods.

5. Equipped with BNR and mute functions.

4. It has path deviation indication.

5. Equipped with multi-layer physical isolation signal sensors, waterproof grade IP65.

6. Built-in large-capacity lithium battery, long standby time, equipped with fast charger.

7. Small and lightweight, easy to operate, and simple human-machine interface.

Technical specification

Working principle

1. Acousto-magnetic synchronization method:

Acousto-magnetic synchronization method is a very accurate and unique method for precise fault location. Its principle is based on the traditional acoustic point determination method and adds the detection and application of electromagnetic signals.

When the high-voltage generator performs impact discharge on the faulty cable, the sound generated by the discharge at the fault point is transmitted to the ground. The sound signal is picked up by a highly sensitive probe. After amplification, a "pop" sound can be heard by listening with headphones.

The built-in probe of the probe receives the magnetic field signal in real time, and uses the principle that the propagation speed of the magnetic field is much higher than the propagation speed of sound to determine the distance of the fault point by detecting the time difference between the electromagnetic signal and the sound signal. Keep moving the sensor position to find the point with the smallest acoustic-magnetic time difference, then the exact location of the fault point will be below it.

Traditional acoustic measurement legal point instruments generally only use earphones to monitor, or are supplemented by the swing of the meter pointer to identify the discharge sound at the fault point. Since the discharge sound disappears in a blink of an eye and is not much different from the ambient noise, it often brings great difficulties to operators who are not very experienced. The acoustic-magnetic synchronization method effectively avoids the above problems of the traditional acoustic measurement method.

2. Pure sound method:

The pure sound method consists of an acoustic vibration sensor, a signal amplifier, a filter circuit, a sampling unit, a processor, a display unit, a power amplifier unit, headphones, etc.

The pure sound method is mainly used to measure high resistance and flashover faults. Its main principle is to use a high-voltage source to apply impulse voltage to the fault cable to cause discharge breakdown at the fault point, and then use the sound generated during the discharge to accurately locate the fault. The acoustic vibration sensor converts the acoustic signal into an electrical signal, which is amplified and filtered by a signal amplifier and filter circuit. Finally, it is restored to sound through headphones, or the intensity of the sound is displayed. The place with the greatest sound intensity is the fault point.

3. Pure magnetic method:

The pure magnetic method can determine the cable path and the precise location of the cable fault point. Its main principle is to use a high-voltage source to apply impulse voltage to the faulty cable, use an induction coil to pick up the pulse signal, and judge whether it deviates from the cable through the characteristics of the pulse signal. When the characteristics of the picked-up pulse signals deviate, it is determined as a fault point.

4. A-frame method:

If a ground fault occurs in a buried cable, we can use the potential difference method to find the fault point. The method is to add a test voltage between the test point of the faulty cable and the ground, then a distributed electric field concentric with the entry point will be formed around the entry point of the cable. There is no potential difference between any points with the same radius in this electric field, but there is a potential difference between any two points with different radii (points A and B in the figure), and when the distance between the two points is fixed, the distance between the two points is The closer the object is, the stronger the potential difference is.

Using this feature, we can move points A and B gradually closer to the center point. When the fault point is exactly between points A and B, the potential difference becomes zero. If it continues to move beyond the fault point, the polarity of the potential difference will be reversed, so that the grounding point can be accurately determined by moving back and forth.

Instrument layout and instructions

Composition of the instrument

1. Cable fault locator: accurately locate cable fault points within the rough measurement range.

2. Probe: including probe, probe, three claws, and connecting rod, connected to the input channel to receive signals.

3. Wear headphones; connect the input channel of the pointing instrument (feedback of the output signal).

4.7-core signal line: connecting cable between the pointing instrument and the probe (connecting the pointing instrument and the probe).

5. Charger: Connect to the charging socket of the instrument for charging.

6.A frame: used when testing using the step voltage method.

7. A-frame connection cable: cable fault locator and A-frame connection cable.

8. Ground pin: A matching accessory for the A-frame.

Specific instruction for the A-frame test method:

Slowly move the A-frame along the cable burial path towards the end of the cable and observe the changes in the red and green bar graphs on the test screen. This reflects a change in the direction of the current.

At a great distance from the point of damage, the red and green bars on the screen appear slightly irregular and small.

When you get close to the fault point, for example about 5 meters from the fault point, you will notice that the red bar graph becomes very large, as shown in the image below.

When you are directly above the fault point or approximately 1-2 meters in front of and behind the fault point, you will notice that the red and green bar graphs become very small and appear on the screen .

Once you pass the fault point, for example about 5 meters from the fault point, you will notice that the green bar graph becomes very large.

This way, by searching patiently, you can find the location of the fault.

XHDD503

XHDD503 is a classic portable underground cable fault pinpointer independently developed and produced by our company. After more than 50 years of precipitation, the acoustic-magnetic synchronization detection technology it adopts has become very mature and widely accepted and recognized by users in the industry.

The XHDD503 cable fault locator is very small and light, it is packed in a protective PVC case, easy to carry after the user finished detection.

The XHDD503 power cable fault pinpointer is designed with a microammeter display, with electrical level adjustment, frequency adjustment and volume adjustment knobs. 

By observing the swing of pointer on the microammeter, you can see the magnetic field strength during the flashover discharge at the fault point. Rotate the electrical level knob to adjust the reference of the magnetic field strength. In the process of path detection, adjusting the receiving frequency can make our ears hear the path signal that is easier to identify. Adjusting the frequency knob during the process of fault location can effectively avoid the radio signal. Adjust the volume during cable fault location and cable path finding, so that our ears hear a more appropriate sound signal.

Technical Parameters

Product Features

1. Synchronously receive vibration waves, sound waves and electromagnetic waves generated during discharge at the fault point;

2. The acoustic and magnetic channels are designed separately and powered separately, with stronger anti-interference ability;

3. Super magnification, detection depth is greater than 10 meters;

4. Ultra-low and low-power design, quiescent current is less than 10mA, and continuous operation is more than 20 hours;

5. Analog meter design, signal strength and trend are clear at a glance;

6. Zero level can be adjusted arbitrarily, suitable for various strong and weak scenes.

1. Pointer meter: indicates the magnetic field strength during flashover discharge at the fault point;

2. Volume adjustment: adjust at fixed point and path so that our ears can hear more appropriate sound signals;

3. Working mode: select working mode (off, fixed point, path);

4. Frequency adjustment: adjust the receiving frequency during path detection so that our ears can hear more easily identifiable path signals. Adjustment at fixed point can effectively avoid radio signals;

5. Level adjustment: adjust the benchmark of magnetic field strength so that the meter head can swing effectively;

1. Input channel: connect to the probe sensor for precise positioning (connect to the probe sensor for path detection);

2. Output channel: connect to dedicated headphones.

Packing list

XHDD503 Underground Cable Fault Pinpointer

Description
The XHDD503 power cable fault pinpointer is designed with a microammeter display, with electrical level adjustment, frequency adjustment and volume adjustment knobs. By observing the swing of pointer on the microammeter, you can see the magnetic field strength during the flashover discharge at the fault point. Rotate the electrical level knob to adjust the reference of the magnetic field strength. In the process of path detection, adjusting the receiving frequency can make our ears hear the path signal that is easier to identify. Adjusting the frequency knob during the process of fault location can effectively avoid the radio signal. Adjust the volume during cable fault location and cable path finding, so that our ears hear a more appropriate sound signal.

Technical Parameters

Product Features
1. Synchronously receive vibration waves, sound waves and electromagnetic waves generated during discharge at the fault point;
2. The acoustic and magnetic channels are designed separately and powered separately, with stronger anti-interference ability;
3. Super magnification, detection depth is greater than 10 meters;
4. Ultra-low and low-power design, quiescent current is less than 10mA, and continuous operation is more than 20 hours;
5. Analog meter design, signal strength and trend are clear at a glance;
6. Zero level can be adjusted arbitrarily, suitable for various strong and weak scenes.

Packing List