A delta-connected balanced three-phase load is supplied from a three phase, 400 V supply. The line current is 20 Aand the power taken by the load is 10 kW. Find the power consumed if the same load is connected in star.

• A. 21.77 W
• B. 16.33 W
• C. 30 W
• D. 3.33 W

Answer: (D)

Type B MCB:
Type B devices are generally suitable for domestic applications.
They are designed to trip at fault currents of 3 - 5 times rated current.

Type C MCB:
Type C devices are the normal choice for commercial and industrial applications
These devices are designed to trip at 5 - 10 times rated current

Type D MCB:
The Type D devices have more limited applications, normally in industrial use where high inrush currents may be expected.
Type D devices are designed to trip at 10 - 20 times.