Power System Protection MCQs Part 19

Power System Protection MCQs Part 19

The least expensive protection for low voltage power system is

The least expensive protection for low voltage power system is:

1. Fuse
2. Circuit breaker
3. Isolator
4. SF6 breaker

Correct answer: 1. Fuse

Also read: Low vs Medium vs High vs EHV vs UHV Voltage Ranges

The grounds wires are located

The grounds wires are located:

1. Below the line conductors
2. In between the line conductors
3. Above the line conductors
4. None of these

Correct answer: 3. Above the line conductors

Also see: Overhead vs UG lines

The directional overcurrent protection comprises

The directional overcurrent protection comprises:

1. Overcurrent relay only
2. Power directional relay only
3. Both of these
4. None of these

Correct answer: 3. Both of these

Back-up protection works when

Back-up protection works when:

1. Primary protection fails
2. Secondary protection fails
3. Both of these
4. None of these

Correct answer: 1. Primary protection fails

Also see: Which of following is correct about back-up protection

Inverse-time current relays are used for protecting

Inverse-time current relays are used for protecting:

1. Alternators
2. Transformers
3. Feeders
4. Transformers and Feeders

Correct answer: 1. Alternators