How to confirm the power of the live wire, neutral wire, and ground wire with an electric pen
1. Judging the live and zero lines
Use one end of the screwdriver of the electric pen to touch one end of the wire, press the top with your thumb, and if the light is on, it is the live wire, and if it is not on, it is the zero wire. You can use a non-contact tester to determine whether it is a live wire or a live wire. The operation method is:
(1) If the electric pen is close to an object with voltage and emits a buzzing sound, it is a live wire. This electric pen can measure AC voltage between 90V and 1000V.
(2) When approaching the zero line without voltage, there will be no sound from the pen, indicating that this is the zero line.
2. Electric pen fire line zero line
Hold the electric pen with the big and middle fingers, hold the pen cap or pen hook with the index finger, and do not touch the metal pen tip on the head to prevent electric shock.
Use the tip of the electric pen to contact the wires separately. When the induction light inside the pen lights up, this wire is a live wire, otherwise it is a neutral wire or a ground wire.
What is charged is not necessarily the live wire. In the event of a fault, both the neutral wire and the ground wire may be charged, while the live wire may not be charged.
3. Multimeter detection of live and zero lines
In addition, a multimeter can also be used to determine the live and zero lines, and the method of distinguishing the zero or live lines with a multimeter is as follows:
(1) Choose an AC voltage range of 750V for the multimeter, with a black probe in the COM socket, a red probe in the voltage range, and a resistance socket.
(2) The black pen is suspended in the air, while the red pen is used for measurement. Pay attention to the reading, with the high number indicating the live line and the low value indicating the zero line. When distinguishing the zero line with a multimeter, the value can be ignored, with the higher value indicating the live line and the lower value indicating the zero line.
When encountering such problems, it is necessary to request assistance from professional electricians to ensure the safety of personal facilities, and self measurement of electricity is prohibited.
The method of measuring zero and live wires with an electric pen
1. Although the three wires had the same color and were not marked at the time, it was easy to determine the live wire. Go to the power switch and close it, then return and measure three wires with an electric pen. One of the wires will definitely make the pen light up, and this wire is a live wire.
2. After distinguishing the live wire, there is only the neutral wire and the ground wire left. To distinguish between zero and ground wires, we need to use commonly used household appliances such as mobile phone chargers, desk lamps, light bulbs, and rice cookers. Using light bulbs as an example to test the zero and ground wires; If the light bulb is on, it is the zero wire; if the light bulb is not on, it is the ground wire, which confirms the live wire and the zero wire.
