IS Codes & IE Rules MCQ [Free PDF] – 8 Objective Questions with Answers

IS 732 provides a code of practice for electrical wiring installations. It covers design, selection/erection and safety-related practices for building/low-voltage electrical installations under its applicable edition.

Under the IS 732 rule referenced by the paper, installation leakage current should not exceed 1/5000 of the full-load current. Limiting leakage is important for shock protection, insulation health and avoiding unwanted protective-device operation.

B — Suitably rated protective devices such as a fuse or MCB, which disconnect the circuit when current exceeds the safe value.

For a large power station, earth resistance should be extremely low so high fault currents can return safely and protective devices operate quickly. The exam's IS 3043-based target is ideally not exceeding about 0.5 Ω.

IS 3043 is the Indian Standard code of practice for earthing. It covers principles and practices for system earthing and protective/equipment earthing, including electrode arrangements and safety considerations.

A — CEA Regulations, 2010. The safety provisions of the Indian Electricity Rules, 1956 were replaced by the CEA (Measures relating to Safety and Electric Supply) Regulations, 2010.

The 2023 edition of India's National Electrical Code includes stronger/current provisions for modern electrical installations, including electric-vehicle charging infrastructure. That emerging installation area is the key focus among the options.

The protective earth conductor is identified by green in the convention used by this paper/IS 732 question. The distinctive earth-conductor colour prevents accidental connection as a live or neutral conductor.