Finding the Live Wire: How to Tell Neutral from Live in Household Plugs

In summary, to find the "live" wire in a household plug, you can use a multimeter and test each slot to ground. The slot with 120v relative to ground is the "live" wire, while the slot with 0V relative to ground is the "neutral" wire. In the US, the longer slot is typically the neutral wire and the shorter slot is the hot wire, with the ground opening at the bottom.
  • #1
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How can I find the "live" wire (household plug)?

After playing with an electrical socket (with caution), I realized there is 120v between the black and ground wires. However, the white is supposed to be "live", black is "neutral", and copper is "ground". Since there is 120v between black and ground, and between black and white, it makes me conclude that the wires were not properly wired, and that the black in my cause is actually "live", while the white is "neutral".

As such, is there a definite way of finding which is "live" and which is "neutral"?
 
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Your method was correct and you found that your understanding of which was which is wrong: the black wire is the hot wire. http://www.lowes.com/lowes/lkn?action=howTo&p=Improve/ElecOver.html
 
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If you have a live outlet, and a multimeter, you can contact the ground with one probe, then reference that to either slot. The slot with 120v relative to the ground is your live contact and the other slot (0V to ground) is neutral. For US applications, the longer slot should be neutral and the shorter slot should be hot. With the ground opening at the bottom, the longer neutral slot is at the right and the hot is at the left.
 

1. How can I tell if my household plug is live or neutral?

In order to identify the live and neutral wires in a household plug, you can use a voltage tester or a multimeter. Simply insert the probes into the holes of the outlet and the tester will indicate which wire is live.

2. What are the potential dangers of mixing up the live and neutral wires in a household plug?

If the live and neutral wires are mixed up, it can lead to electrical shocks or fires. This is because the live wire carries the full voltage of the circuit, while the neutral wire acts as the return path for the current. If these wires are reversed, it can cause appliances to malfunction and potentially cause harm.

3. Can I use color to identify the live and neutral wires in a household plug?

While color coding is often used for electrical wiring, it is not a reliable method for identifying the live and neutral wires in a household plug. This is because the color coding can vary depending on the country or region, and it is not always consistent. It is best to use a voltage tester to ensure accuracy.

4. Why is it important to know which wire is live and which is neutral in a household plug?

It is important to know which wire is live and which is neutral in a household plug because it ensures the safe functioning of electrical appliances. If the live and neutral wires are reversed, it can cause appliances to malfunction and potentially lead to dangerous situations.

5. Are there any other methods for identifying the live and neutral wires in a household plug?

Aside from using a voltage tester, another method for identifying the live and neutral wires is by using a plug-in circuit analyzer. This device can quickly and easily determine if the wires are correctly connected in a household plug. It is important to always use caution when working with electricity and to seek professional help if you are unsure.

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