In a circuit, a wire that has live electricity passing through it is called a hot wire. In residential buildings, these wires are typically colored black and red. In situations in which a wire is renamed as “hot”, it is marked with a bit of black electrical tape. This helps to avoid problems that arise when wires are not recognized properly and the right connections cannot be made. When this happens, and a hot wire can’t be properly identified, the device needs to be tested with the circuit on to identify the hot wire.
Listed below are a few questions answered by electricians on issues relating hot wires.
Yes, this is what is usually done in a situation like this. You need to use a marker or black tape to mark the white wire to identify it as a hot wire.
Whenever you work on anything that is electrical, ensure that the power is turned off. If you need to keep the power on, you would need to first disconnect the hot wire and cap off to prevent it from coming into contact with any other wires. Then you can proceed to remove the neutral and ground wires safely and reinstall them in reverse. All that is required are two touching points, a hot one and a neutral or ground one, or anything grounded, to cause harm or trip the breaker. Also, remember to always use a fiberglass ladder for added safety when you undertake electrical work.
If you want to find the hot wire, you first need to get a ground or neutral reference point. You can use the ground wire in the box or if the box is grounded, that will also help. Start by bringing one lead from the tester into contact with the ground and the other to either one of the black wires. Thereafter, test the other black wire. The black wire that measures at or near 120V is the “hot” wire. In the event that you don’t have a ground in your box, get an extension cord and run it from one of the receptacles at home. This receptacle and the plug end of the extension cord should both possess a larger slot and a smaller slot. Treat the wider end as "neutral" and use this as your ground reference for testing the black wires. Insert one lead into this neutral slot on your extension cord and the other one to a black wire. Then repeat the test on the second wire. The one that gives you at or near 120V is your "hot" wire.
Hot wires can be dangerous and there are several things you need to keep in mind while handling them. To begin with, always make sure the power is turned off at the breaker box before you start any electrical repairs. Place a sign on the box that lets everyone else know repairs are going on and the power should not be reconnected under any circumstance. Also, make sure you never stand in any kind of water while doing electrical work as water can conduct electricity well and result in electrocution. Many states require an individual to have undergone special training or to have a special permit before taking on electrical work. That’s why sometimes it’s best to hire a licensed electrician to handle electrical repairs.