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SarkariResultOutAdditional Assistant Engineer (Electrical) · 2026

Previous Year Question

In large buildings, internal power distribution is generally carried out using ________________.
  1. Single extension cords for all loads
  2. Portable generators exclusively
  3. Rising mains, bus ducts, or distribution boards
  4. Temporary wiring arrangements for circuits

Correct answer: C

Explanation

Large buildings use structured distribution systems such as rising mains, bus ducts and distribution boards so that power can be distributed safely, selectively and with suitable protection at different levels.

Step-by-step solution

Rising Mains and Bus Ducts explanatory diagram

Correct Answer

C — Rising mains, bus ducts, or distribution boards

Explanation

Large buildings use structured distribution systems such as rising mains, bus ducts and distribution boards so that power can be distributed safely, selectively and with suitable protection at different levels.

Key Concept

Rising Mains and Bus Ducts

Exam Point

Large building = bus duct/rising main + distribution boards.

Exam tip

Large building = bus duct/rising main + distribution boards.

Quick method

Large building = bus duct/rising main + distribution boards.