You can use a current tester or voltage meter to determine whether an electric cable is hot. Note that more than one cable can be alive. Tap the meter or meter tip at the screw in which the cables are connected. Go slow and hold your eyes and ears open.

With a live circuit, you can identify the controller of the live switch in the mounting of the light. Alternating the switch will make the live switch one of your blacks. With a multiple digital meter you will configure this AC volt. When the switch is closed, you will see 230 V between the neutral and black live switch.

If you see an electric line down, step away from it and everything that touches it. The terrain around the electric lines up to 35 feet away - you can energize. You can't tell if an electric line is energized just looking at it. You have to assume that all the electric lines down are live.

Build your own tester. For example, get a light bulb and plug, and attach a few cables to it. Then tap one for neutral or to the ground and one for the thread-subtest. If the lamp is turned on, it is alive.

Use the wire detector to know exactly where the wire crosses the walls. Use the wire detector and focus on specific areas where the wire is suspected. A wire detector is simply a type of metal detector that is able to detect the presence of metal objects on the walls.