Electrical Wire Nuts for Splicing and Grounding Wires
In old installations, wire splices often were covered with thick electrician's tape. That is not only a slow way to cover a splice but also a code violation. Cover every splice with an approved wire nut.
Assemble a collection of various-size nuts so you are ready for any splice. Wire nuts are color-coded according to size. The colors and sizes may vary according to manufacturer. Read the packaging to make sure the nuts you buy fit over your splices.
Smallest Wire Nuts
The smallest wire nuts — which usually come with light fixtures — are often white, ivory, or blue. If these have plastic rather than metal threads inside, throw them away and get orange connectors with metal threads for a secure connection.
Orange Wire Nuts
Orange nuts are the next size up and can handle splices of up to two 14-gauge wires.
Midsize Yellow Wire Nuts
Midsize yellow wire nuts are the most common. Use them for splices as small as two 14-gauge wires or as large as three 12-gauge wires.
Red Wire Nuts
Red connectors are usually the largest wire nuts and can handle a splice of up to four 12-gauge wires.
Green Wire Nuts
Green wire nuts are used for ground wires. They have a hole in the top, which allows one ground wire to poke through and run directly to a device or box.
Gray Twister Wire Nuts
Gray twister wire nuts are designed to be all-purpose — they can handle the smallest to the largest splices. However, they are bulky and expensive.
B-Cap Wire Nuts
B-cap wire nuts are slim, which makes them useful if a box is crowded with wires.