Everyone should be familiar with the live cable identifier. Xiaobian introduced it in the previous article. It is a very common cable construction and maintenance equipment. At present, there are both instruments for identifying non operating cables and instruments for identifying operating cables. Now we will introduce some knowledge about live cable recognizer. 1ã The transmitter panel of live cable identification instrument is introduced as follows: 1. Signal output port: this port sends the signal to the cable to be tested through direct connection coupling. The instrument can automatically detect the connection mode (direct connection or coupling). When no output line is connected to this port, the screen mode menu displays idle, and no signal is output at this time. 2. Frequency switching: the instrument has four output frequencies: low frequency, intermediate frequency, high frequency and radio frequency. It is suitable for different test systems and has strong anti-interference ability. When this button is pressed, the frequency will be switched between the above frequencies in turn. 3. Power regulation: the instrument adopts constant power output mode, and low, medium and high gears are optional. When this button is pressed, the power will be switched between the above gears. 4. Backlight switch: the instrument has a backlight controllable function. The backlight can be turned off during the day to save power. At night, the backlight can be turned on for test. When this button is pressed, the backlight will be turned on. When it is pressed again, the backlight will be turned off. 5. Power switch: the main switch of the whole instrument. When this button is pressed, the instrument enters the test interface. 6. Liquid crystal display of cable identification instrument: the instrument adopts liquid crystal display for man-machine dialogue. 2ã Precautions for the use of live cable identifier 1. If the operating cable has voltage and there is no load, there is no current flowing on the cable. At this time, the magnetic field cannot be detected. It is considered to be an uncharged cable, which is very easy to misjudge. 2. If the cable is not running, but if this cable is parallel to other running cables, there will be induced current and magnetic field. At this time, the instrument will also have indication, and misjudgment will occur. 3. If there are multiple cables in the cable trench, these multiple cables will generate a magnetic field. At this time, there will be a magnetic field generated by 50Hz current in the whole area. At this time, there will be a magnetic field in the whole area, which makes the discrimination impossible. It is easy to misjudge. 3ã Basic parameters of live cable recognizer insert the red and black wiring plugs of the transmitting caliper a into the two red and black wiring posts corresponding to the transmitting source, and clamp the transmitting caliper a on the identified cable. The arrow on the transmitting caliper a points to the cable terminal. On the identified cable two meters away from the transmitting caliper, clamp the receiving caliper B to the cable, and the arrow on the caliper must point to the cable terminal. Then check the current direction and test connection direction. At the identification point, identify each cable with receiving caliper B. During identification, the arrow on the receiving caliper must always point to the terminal direction of the cable, and the cable shall be clamped one by one. On the identified cable, the current meter pointer of the receiver must be deflected to the right, and the audible and visual alarm prompt shall be given at the same time.