Electrical Wiring and Cable Installation Flashcards

Which cable type is specifically rated for direct burial underground installation?

Answer: UF-B (Underground Feeder)

UF-B cable is rated for direct underground burial because it has a moisture-resistant, sunlight-resistant outer jacket.

Why are cables sometimes installed with armoring in electrotechnical work?

Answer: To protect against physical damage in industrial or hazardous environments

Armored cables (such as MC cable) have a metal sheath that protects the conductors from physical impact and abrasion in demanding environments.

What is the purpose of cable trunking in an electrical installation?

Answer: To organize and protect multiple cables running along the same route

Cable trunking provides an organized raceway that protects, contains, and routes multiple cables neatly through a building.

How should cables be identified in a multi-circuit electrical installation?

Answer: Using color-coded insulation and circuit labels or tags

Cables must be identified using standardized color codes and circuit labeling so that any electrician can safely identify circuits during maintenance.

What is the function of a cable gland in an electrical installation?

Answer: To provide a secure, sealed entry point where a cable enters an enclosure

A cable gland clamps onto the cable sheath to provide strain relief and an IP-rated seal at the point where the cable enters a junction box or panel.

What does the term 'diversity factor' mean in electrical installation design?

Answer: The assumption that not all loads will operate simultaneously, allowing smaller supply cables

Diversity factor recognizes that all connected loads rarely operate at full power simultaneously, allowing the supply circuit to be sized below the sum of all individual load ratings.