Featured Deals:
Black Light Outdoor
hi i live in a older home with older wiring and i was going to install a outdoor light both wires are black?
one wire is on the right one is on the left of the mounting box they are both black which one is positve which one is neagative
If the home is old enough, the wiring was usually done with a method called knob & tube, where the hot wire and the neutral were run separately from each other. Each wire would have really thick stiff black insulation. By the 40's and 50's, BX tubing became popular, where the two wires would be run together inside a flexible metal sheath. These may or may not be colored differently. By the late 60s/70s NM cable because popular. This is what's used today: two or three conductors plus a bare ground inside a plastic sheath.
The fact that both your wires are black does not mean there is a problem. Although you could theoretically reverse them when wiring to a simple light fixture without a problem, it is best that you find out which one is hot and which one is neutral. That way you can wire the hot one to the black wire in the new fixture, and the neutral one to the white wire in the new fixture. Doing this will adhere to building code, and will allow future remodelers to know which wire is the hot lead. To find out which one is the hot lead, purchase a small pen tester for about ten bucks at home depot like the one shown in the links below:
Hold the tip against both wires, one at a time, with the light switch on. The wire that makes the pen beep is the hot wire. The other one is neutral. Next, remove the fuse, or open the breaker for the outdoor light so that you can be absolutely sure that when you work on it you have nothing live. Don't rely on the switch, because sometimes the circuit is wired with a "hot neutral". meaning there is voltage at the light even with the switch off. If you're not sure which fuse or breaker to pull, then pull the main breaker so that the whole house is off. Wire the new fixture so that the fixture's black (or brown) wire connects to the "hot" wire you found coming out of the house. Wire the fixture's white (or blue) wire to the neutral wire coming from the house. When using wire nuts, strip the insulation off each pair equally, twist on the wire nut and keep twisting until the insulation starts to twist too. If there is a bare copper wire coming out of the house along with the two black wires, twist it to the bare copper wire coming from the new fixture. Twist it good, then attach it to the metal electrical box using a screw that is usually found in the box. If the electrical box is plastic, just twist the bare wires together.
Current EBay auctions for Black Light Outdoor
