A 20 MVA, 11 kV generator is protected by a percentage differential relay. The CT ratio is 1000/5. The relay has a pickup current of 0.2 A. What is the minimum internal fault current in amperes that will operate the relay, assuming no restraint?

According to standard electrical installation practice (such as IS 732), the permissible leakage current in an installation must not exceed 15000 of the full-load current. For a building installation with a 2.4 kW load on a 240 V system of supply, what will be the minimum permissible insulation resistance to earth?

A moving coil instrument has 100 turns, a coil width of 20 mm, and a coil depth of 30 mm. The magnetic flux density in the air gap is 0.1 Wb/m2. If the deflecting torque produced is 30 × 10-6 Nm, calculate the current passing through the moving coil.