White wires are always neutral in 110 volt circuits but can be used as the second hot wire or switch leg in 240 volt applications and three way switches respectively. Never attempt to use a black wire as a neutral or ground wire.
Electrical Wiring Wikipedia
Old house wiring red black white. Identifying house electric wiring colors written by. The wiring in some. Green wires are used for grounding and should only be. When measured with respect to the white neutral wire the red wire carries the same 120 volt current that the black one carries making the voltage across these two hot wires 240 volts. When you see either a green wire or a bare copper wire you can be sure it is a ground wire. The white is always neutral and green or bare is ground.
So what they probably did was make a connection with new wire from the breaker panel red black and. You might find them on fans or lights where they can assist a multi way switch. Red wires are also hot wires. A ground wire is used as a protective measure. One of the hot wires attaches to a brass terminal on one side of the outlet and the other attaches to a brass terminal on the other side. Sheathed cable with a red wire always is accompanied by a black wire a white wire and a bare wire.
Youll have two cables in the switch box a live one with a black and white wire and the one going to the outlet which has a red black and white wire. 12 awg for 20 amp circuits and 14 awg for 10 and 15 amp circuits. Red wires are usually secondary live wires in circuits. Do not connect both red and black unless you know the fan is wired for. My house was built in the 50s with wiring from that time period. Very old homes may have cable that excludes the bare wire.
If you are writing from north america both red and black are used as hot. That is 120v each between the two is 240v. Ground wires return fault current to earth ground protecting the individual from electrocution. Join the black wires from both cables together add a 6 inch jumper cable of the same gauge twist them all together and screw on a wire cap. Join the white wires and cap them in the same way but omit the jumper wire. Blue and yellow wires are usually live wires as well.
Original old house wiring was often red and black with no white wire. They should both be of the same wire gauge. White and gray wires are almost always neutral. A white wire that has been marked with black means its acting as a hot wire and is no longer neutral. If you have the previous colours red black and green earth or bare earth very dangerous we would recommend you have an electrician test to check the integrity of the cable as it could be more than 50 years old and unreliable. You should also be looking at the condition of cables as well as the sheathing of the cables.
A white wire may be marked with a piece of black electrical tape at its ends. As hot wires can be connected to each other a black wire can be connected to a red wire. Im trying to understand how to connect a modern switch up in the place of an existing old one and it just isnt making sense to me.
Gallery of Old House Wiring Red Black White
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