Correct method of voltage meter tester pen
If the voltage test pen is used improperly, it will not only cause errors in the test, but also may cause an electric shock accident.
When conducting an electricity test, press the metal body at the end of the test pen with the index finger of the right hand, hold the body of the pen with the thumb and middle finger, and the small neon window with the backlight facing you. superior.
If the neon tube of the electric pen glows, it means that the device under test is electrified, and the neon tube moon, the higher the voltage; if the neon tube does not glow, it means that the device under test is not electrified.
1. Use an electroscope within the rated voltage range
The voltage range of ordinary electroscopes is between 60V and 500V.
If it is used to test a voltage lower than 60V, the neon tube of the test pen may not emit light, which will cause misjudgment; if it is used to test a voltage higher than 500V, it is easy to cause electric shock. 【Safe use of electroscope and correct method of electroscope】 Therefore, electroscope is only allowed to be used within the specified rated voltage range.
2. Take measures to prevent electric shock and short circuit during electricity inspection
When using the electroscope, never touch the metal probe and live equipment at the front of the electroscope with your hands, otherwise, it will cause an electric shock accident.
When using a screwdriver-type electroscope, the longer part of the pen head should be covered with an insulating plastic sleeve, leaving only a metal head of about 10 mm for testing.
The distance between the phases and the relative ground of the low-voltage equipment is small. If the above protective measures are not taken, it is easy to cause a short circuit between the phases and the relative ground.
When testing electricity with a test pen, the operator should keep the operation stable, and the pen end should not be in contact with the two wires to be tested at the same time. Touch and cause short circuit injury.
In addition, in order to prevent electric shock accidents caused by the use of unqualified electric test pens, professional electricians should wear insulating shoes and stand on insulating objects such as dry wooden boards and benches during electric inspection.
3. Correctly distinguish equipment leakage and static electricity
The metal casing of some equipment is not grounded or connected to zero protection, and its casing is often electrified due to induction. The neon tube will also light up during electricity inspection, but this electrification generally does not constitute an electric shock hazard.
In this case, electricians can use test lamps, multimeter resistance gear, megohmmeters and other measurements to distinguish them.
In addition, an electric test pen can also be used to distinguish whether the equipment is leaking or has static electricity. The electric test method is: touch the charged equipment with an electric pen. If the neon tube flashes for a while, then it goes out, which proves that the device has static electricity; if the neon tube flashes for a long time, It's a power leak.
