QTQ-02 cable detector, underground cable detector, detector cable 

 QTQ-02 cable probe for use 
 First, the purpose and scope: 
 Detector is the communication cable, power cable construction and maintenance of common equipment, underground cables and metal can determine the exact location and pipeline burial depth, or the determination of overhead cable wire barriers and accurate parts. For the cable, pipeline expansion service providing a convenient conversion, control can reduce the open ground, save manpower, material and time, so the post office and industrial and mining enterprises is an essential instrument. 
 Main purposes: 
 (1) to detect the direction and depth of underground cables. Playback using the cable wire, with One probe detection, depth of 1.5 meters of cable effective detection range of more than 25 km. Depth of 2.5 meters of cable and effective detection range greater than 10 km, flat position error greater than 5 cm. 
 (2) to detect underground metal pipes (pipes, steam pipes, water pipes) the direction and depth, from the metal pipe playback (playback cable lead sheet), with a large probe detection. 
 Effective detection range of more than 1000 meters. 
 Effective probing depth of 200 meters up to 7 meters. 
 600 meters up to 5 meters. 
 1000 meters up to 3 meters. 
 (3) overhead cable wire obstacle detection site. 
 Mixed overhead line wire cable, to gas, the sticking point when the contact resistance of less than 2000 in Europe, with the II probe can accurately determine the barriers to their home. 
 (4) If configuring a measurement probe (ground rules), we can measure the underground plastic cable insulation bad (in air) of the accuracy of their home. Can find 15 km of 2.5 megohm leakage resistance following poor insulation barrier. Unshielded plastic cables buried underground mix line, to the gas barrier point, can also be detected at the probe on the ground out. 
 Second, the basic principle: 
 Audio signal from the oscillator generates a current, flowing through the cable under test (metal pipe) constitute a circuit through the earth. This current generates a magnetic field around the system under test, magnetic field lines through the earth to the ground, on the ground with a pick-up coils to detect magnetic signals, amplified by the receiver frequency selection after listening with headphones, so this test can determine the magnetic field changes the location of underground metal pipe. The same principle can lead sheet in the cable outside the test site within the core wire barriers. 
 The instrument has a high anti-interference ability, because the playback signal oscillator frequency selection in 512 weeks, is placed beyond the power harmonic interference, to avoid their interference, the receiver signal amplification only 512 weeks, the frequency of other signal attenuation are sufficient to ensure the reliability of the instrument. 
 Third, the instrument introduced: 
 The instrument mainly by the oscillator, the receiver, large probe, small probe. One is described as follows: 
 1, the oscillator: 

 Oscillator with impedance selector switch panel, then use a good line after playback, rotate the switch to match a file with the external circuit, the maximum output power at this time, the greatest number of the meter indication, the use of lead sheet playback, Only in the case in order to match the effective detection range of the maximum. 
 Meter can also be used to measure battery voltage, press the "Power Test" button, such as hands not red, the battery less than 13V, replace the battery. 
 Another use of the meter is connected to monitor the playback of the line from the output terminals connected to a playback or remove the line, the reading should be significant changes in electric blue, or that the playback line is not connected, or point of contact is not polished clean, contact resistance is too large. 
 2, the receiver 
 Receivers equipped with meters, can significantly change the comparison signal, such as electricity, said that reading the meter reading is not obvious can be rotated to adjust the control knob, so the detection of cable barriers, in order to compare the size of the signal before and after the sticking point, we must remember that the original file bit and meter readings, high sensitivity than the headphones. 
 In all cases the volume control knob should be open to a minimum, just to hear the sound in the headset until it is excessive because the probe cable will sound dumb points wider scope to increase the measurement error. Detect obstacles in the cable core, the sound excessive, will not change significantly before and after the sticking point. So keep in mind this principle is very important. 



 3, the large probe 

 For the detection of underground cable (metal pipe) special, part of a probe locator probe and probe into the 0 °, 45 °, 90 °, rotation, 90 ° for the buzzer method used, 0 ° for the selected point method using dumb , 45 ° is used to detect depth. 
 4, the small probe 
 Line formed by the probe and, for the detection of aerial and cable. 


 The use of methods: 
 1, the playback method to detect wire routing and depth of underground cables. 
 For the construction business, cable or not this method can be effective within 25 km detection. 
 (1) the oscillator on one end of the cable, choose a good cell line for playback line to the output terminal, which the root line of remote playback should also be connected to the gas bar on the other root. Another output terminal connected to another output terminal connected to the gas bar on the other root, so that the current composition of the playback loop. 


 (2) clockwise "output control" power on, adjust the "sensitivity meter control", so that hands are clear values, and to prevent meter firing pin. 
 (3) the panel on "continuous an discontinuous" switch into the "continuous." 
 (4) adjust the "resistance option" to stop the meter reading is the largest one file, the output impedance and the external circuit impedance. 
 (5) current test button is pressed, check the battery voltage is greater than 13V, or should replace the battery. 
 (6) and then "a continuous intermittent" switch into the "intermittent" to save the battery. 
 (7) the headset and the corresponding plug the receiver into the probe hole, D "volume control", power on, adjust the volume, in the playback point can be heard around the clear tones, said apparatus intact. 
 (8) to pull to the large probe and probe into the probe at 0 °, the probe tube axis perpendicular to the ground, since the playback point to the remote road, dumb the next point is the positive cable location. (Figure 6) moves the position of the probe sequence (Figure 7), 2,4,6 ······ point is dumb, dumb points of the cable line is the trend. 


 Large probe will rotate 90 °, so that the probe tube axis and parallel to the ground with the cable into the 90 °, then the maximum volume of the headset, this point called the peak sound points, just below the peak sound points for the cable position. (Figure 8) 


 (9) has been measured according to a good cable, 2 meters to draw a straight line, then draw on the ground perpendicular to this line. 
 (10) to pull the probe to 45 °, the probe slowly sagging natural vertical movement along the cable, the cable should be noted that both the probe axis should be pointing left and right cables, this will also be dumb and mute point 2 point 1 . (See Figure 9). At this point D (depth) = L1 = L1 or D = 2 / L1 + L1. As a branch or bend the cable distribution of the magnetic field is more complicated, so the cable must be measured within the depth of line segments. 
 2, the cable lead sheet playback method to detect underground cable and pipeline route and depth of the metal. 
 Have a business need to use the cable or lead sheet metal pipe playback method. Since this method consumes a large current, so the detection range will be greatly reduced. 
 (1) Select the playback point; 
 In order to expand the effective detection range should be selected playback point, for example, a sub-branches have A, B, C three cables to detect cable B, it should be in the B-side to the A-side playback, because, as in the A-side playback, the signal current is A, C cable diversion, (Figure 10). For the T-joint metal pipe is also a similar situation, should be used with care. 
 (2) the oscillator output terminal to the cable or lead sheet metal pipe and the other two output terminals connected to the gas stick, air stick to hit about 10 meters away from the cable and go with the cable into the 45 ° angle position (Figure 11).