Electrical tape

Electrical tape (or insulating tape) is a type of pressure-sensitive tape used to insulate electrical wires and other materials that conduct electricity. It can be made of many plastics, but vinyl is most popular, as it stretches well and gives an effective and long lasting insulation. Electrical tape for class H insulation is made of fiberglass cloth.

According to a Popular Mechanics article in 1973, "Plastic tape is also known as electrical tape." A wide variety of electrical tapes is available; some for highly specialized purposes. "The primary tapes used in electrical applications are vinyl, rubber, mastic, and varnished cambric."Electricians generally use only black tape for insulation purposes. The other colors are used to indicate the voltage level and phase of the wire. (In fact, the colored tape is referred to as "phasing tape".) This is done on large wire which is available only in black insulation. When wires are phased, a ring of tape is placed on each end near the termination so that the purpose of the wire is obvious. The following table(s) describe the use of electrical tape.

Tape that is approved for electrical applications will carry an approval label from an agency such as Underwriters Laboratories. Skills and training are important as well.

As it is easily torn by hand, can be written on, and generally removes from smooth surfaces cleanly, it is useful for a number of other applications such as labelling (including colour-coding) and temporarily attaching objects to one another. It can be torn by hand or cut with tools.

In Pakistan and India, electric tape is very commonly used to wrap a tennis ball for purposes of playing backyard cricket. The electric tape provides a smooth surface, causing the tennis ball to grip a concrete surface less, makes the ball harder to hit, and causes it to bounce less. These properties make the ball behave more like a leather cricket ball, yet still being substantially cheaper and less dangerous.

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