Unit 1-1 Lesson 10

Rank the conductors by size, from smallest to largest.

6 AWG < 4/0 AWG < 500 kcmil

Unshielded cable use is normally limited to ? .

7.2kV

Identify the stranded conductor represented by each diagram.

Annular Concentric Round Compact Round Compact Sector

The diagram above shows seven layers of a shielded cable labeled A through G. Identify the layer of the cable represented by each letter.

Cable Jacket Bedding Tape Metallic Shielding Semiconducting Material Insulation Strand Shielding Conductor

Ampacity is the amount of voltage that a conductor can carry without exceeding an acceptable temperature rise.

False

Annular conductors are used for larger size cables to increase skin effect.

False

Cable sheaths cannot be made from metallic materials.

False

With regard to cable jacketing, the letters PVC stand for Pre-varnished Cambric.

False

Aluminum conductors can be damaged by ? when touching other metals in the presence of water.

Galvanic action

The diagram shows four layers of an unshielded cable labeled A through D. Identify the layer of the cable represented by each letter.

Jacket Insulation Strand Shielding Conductor

Cable with impregnated-paper insulation has a ? sheath.

Lead

Varnished-cambric insulated cable normally has a ? sheath.

Lead

Three of the most common materials used as insulation for power cables are taped insulation, thermoplastics, and ? .

Rubber

Strand shielding is made from ? materials.

Semiconducting

Large power cables use ? , which makes the cable flexible.

Stranded conductors

Bedding tapes are used in cables to add mechanical strength.

True

Copper conductors have a higher conductivity than aluminum.

True

Lead sheathing is the most effective type of protection for insulation against moisture, weather, and oxidation.

True

Voltage, current, and ambient temperature are three factors used to determine the type of cable insulation for a specific use.

True