Exam 25: Television, Telephone, and Low-Voltage Signal Systems

Which of the following rules apply to coaxial cable installations under Article 820?

When 120-volt receptacles and TV outlets are mounted in double-gang boxes, ____ is required in the box to isolate the TV conductors from the power wiring.

Never install electrical equipment, junction boxes, or conduit boxes above a ____________________ closed-in ceiling or within a wall.

Television antennas and lead-in wires are covered under Article ____.

The type of cable most often used for television signal distribution in new residences is ____.

Because TV is a low-voltage system, metallic or nonmetallic standard single-gang device boxes, 4-in. square ____________________ with a plaster ring, plaster rings only, or special mounting brackets can be installed during the rough-in stage at each likely location of a television set.

When coaxial cables are run underground, they must be separated at least ____________________ inches from underground light and power conductors, unless either the coaxial or power cables are run in a raceway.

On the outside of a building, position and fasten lead-in conductors so they cannot swing closer than 24 in. (600 mm) to light and power conductors having not over 250 volts between conductors; 8 ft (3.0 m) if over 250 volts between conductors.

A ____ is described in the NEC as any electric circuit that energizes signaling equipment.

The article that covers cable TV wiring installations in residences is Article ____.

NEC 725.121(B) prohibits connecting transformers in ____________________ unless specifically listed for interconnection.

Antennas and lead-in conductors may be attached to an electric service mast if they are kept a minimum of 36 in. (900 mm) below the power conductors.

The point where the telephone company ends and the homeowner's interior wiring begins is called the ____________________.

Transformers and low-voltage wiring for doorbells are classified as ____ circuits under Article 725.

Chime transformers used in dwellings are generally rated ____ volts.

Keep the antenna and lead-in conductors at least 2 in. (50 mm) from other open wiring (as in old houses) unless the other wiring is in a(n) ____________________ or cable.

Chime transformers are listed as ____________________ because of their low voltage rating and power limitation.

The NEC _____ in a dwelling.

Residential telephone conductor installations must be made in accordance with the requirements of ____.

Telephone conductors must be separated by ____________________ from light and power conductors unless the light and power conductors are in a raceway, or in Type NM cable, Type AC cable or Type UF cable.