Using an induction test pen
Commonly used low-voltage test pens, master the two-grip method of testing. A pen-style tester, the metal clip is pressed against the palm of the hand. Thumb index finger and middle finger, pinch the middle of the electric pen barrel. Rotary chisel-type electric measuring pen, the index finger presses the tail metal cap. With the thumb, middle finger and ring finger, pinch the middle of the plastic rod. The small window of the neon tube is backlit, and you can observe it by facing yourself.
Precautions for using the induction test pen:
1. Before using the test pencil, first check whether there is a safety resistor in the test pencil, and then visually check whether the test pencil is damaged, whether it is damp or water, and can only be used after passing the inspection.
Principle: There is a resistor in the test pen, and there is a luminous body - a neon tube. The key lies in the neon tube. After the resistance is lowered, there is a voltage to one end of the neon tube to form a high potential. Your hand needs to touch the metal end of the electric pen. , now you are the ground wire. There are two thin metal wires in the neon tube, which are very close to each other, but they are not connected. The neon tube is naturally filled with neon gas, and a glow can be produced if there is a suitable potential difference. discharge. If the voltage is too high, it will break down the neon tube instantly. At this time, the neon tube will act as an insurance and will not cause too much harm to you. Low voltage will be more dangerous, because the traditional electric pen is a neon tube electric pen, and it is only about 100V or more. It will light up, don't be careless, and don't let the electric pen get into the water, or you will know the feeling of electric shock.
2. When using the test pen, do not touch the metal probe at the front end of the test pen with your hands. Doing so will cause personal electric shock accidents.
3. When using the test pen, be sure to touch the metal part at the end of the test pen with your hands. Otherwise, because the electrified body, the test pen, the human body and the earth do not form a circuit, the neon bulb in the test pen will not emit light, causing a misjudgment. The charged body is not charged, which is very dangerous.
4. Before measuring whether the electrical equipment is charged, first find a known power source to test whether the neon bulb of the electric pen can emit light normally, and then it can be used.
5. When testing the charged body under bright light, special attention should be paid to whether the neon bulb is really glowing (or not). If necessary, use the other hand to block the light to judge carefully. Do not cause misjudgment, judge that the neon bulb glows as not glowing, and judges that there is electricity as no electricity.
