How to confirm ground and zero wire by electric pen? Electricity stylus measuring zero wire fire wire ground wire
How to confirm ground and zero wire by electric pen? Electricity stylus to measure zero wire fire wire ground wire
1, energized, measured with an electric pen, the one that will be bright is the fire wire.
2, will be disconnected from the zero line, only connected to the fire wire, the lights at home in the open position, with the electric pen measurement, another will be bright is the zero line.
3、The rest is the ground wire.
Zero and ground wires directly with
Pen is not measured, they are not charged to ground, so the test pen will not be bright. Fire wire can be tested with a test pen.
In the case of residual current protection device (earth leakage circuit breaker), you can distinguish between the fire wire and the zero wire by experimenting, connecting a light bulb between the fire wire and the zero wire, the light bulb glows normally, while connecting a light bulb between the fire wire and the ground wire, the earth leakage circuit breaker will trip immediately.
Household electricity, generally 220V ~ 250V single-phase electricity, from the fire line through the load such as light bulbs and other appliances through the zero line to form a circuit, the appliances can work properly. Part of the shell for the metal appliances, but also need to connect a grounding wire, when the shell of the appliance accidentally charged can be led to the ground to ensure the safety of electricity.
In the wiring and routine maintenance, in order to be able to distinguish between different uses of the wire, generally use different colors to distinguish.
Fire wire generally use warm color wire, the most common is red wire. If the pursuit of more standard construction, different circuits can use different colors of fire wire to distinguish, in addition to the red wire, you can also use yellow wire and green wire. However, the use of multiple colors to distinguish a certain degree will increase the cost of wire procurement.
Zero line generally use cold color wire, the most common is blue wire, some also use black wire.
Ground according to the standard can only use yellow and green two-color line, because the ground is very important to the safety of electricity, so its color requirements are very strict, can not use other colors of the line instead.
According to the color points
Red fire wire, blue zero line, yellow and green two-color ground wire.
If the color can not be distinguished
In practice, give you three wires, one is the fire wire, one is the zero line, there is a ground line, if the three lines of the same color! How can you distinguish between them?
1, the correct connection is: phase line (L) generally use red or brown; zero line (N) zero line with blue or green; protective earth (PE) color shall be used with yellow and green lines.
2, with an electric pen to measure the fire line, will use a clamp-type ammeter? Phase line (fire) and the zero line of the current is the same, the ground line is normal when there is no current.
3, the zero line is a current flow; ground is for protection, no current for normal operation, only short-circuit and leakage current, the requirements of the grounding resistance is very small, the equipment end of the general shell protective grounding.
Measured with an electric pen out of the fire wire, the test lamp (with a line bulb) on the fire wire and the other two wires in one, if the light is on that is 0 line. If the light is not bright. Explanation is the ground wire. (Test light method, in the case of the ground line is not connected to the earth is effective, such as the ground line is connected to the earth, then regardless of the connection of that one line light will be lit .)
4, in the case of a power supply, find the firewire should not be difficult, difficult to distinguish between the zero line and the ground, theoretically: the firewire and the zero line between the voltage in the 220 right, and the voltage between the ground line at 190 volts or so. Connect an energy-saving lamp, then the brightness should be able to see, bright nature is the zero line, just for reference.
5, there is a simple way
We are using a test light (with a light bulb) on the firewire and the other two wires in a line, if the light is on that is 0 line. If the light is on a leakage switch open jump. That is the ground.
