Question

In: Electrical Engineering

A 440 VDC, 60hp, cumulative compound long shunt motor has an armature resistance of .1 Ohm,...

A 440 VDC, 60hp, cumulative compound long shunt motor has an armature resistance of .1 Ohm, a series field resistance of ??? Ohms and a shunt field resistance of 80 Ohms. The brush drop is a constant 2 volts. The stray losses are 2.5 kW. The CEMF at rated load is 393 volts. Draw the electrical circuit, then determine the following for the above conditions:

A. The armature current:

B. The power developed by the armature:

C. The resistance of the series field:

D. The starting current if motor is directly connected across the 440 line voltage?

E. The value of a starting resistor to limit the initial current to 150A.

F. The nominal line current when operating at full load?

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