If the primary fault current is 2000 A, the relay setting is 50% and CT ratio is 400 : 5, then plug setting multiplier will be

Electrical Engineering MCQ

If the primary fault current is 2000 A, the relay setting is 50% and CT ratio is 400 : 5, then plug setting multiplier will be:

Current answer: 4. 10

Explanation:

Pick up Value = Rated secondary current of CT × Current Setting

= 5 × 0.5 = 2.5 A

Fault current in relay coil = 2000 × 5/400 = 25 A

Plug setting Multiplier = Fault current in relay coil/Pick up value

= 25/2.5 = 10

If the primary fault current is 2000 A, the relay setting is 50% and CT ratio is 400 : 5, then plug setting multiplier will be – Electrical Engineering MCQ