Question 40.9: A shunt motor, supplied at 250 V, runs at 900 r/min when the...

Hughes Electrical and Electronic Technology

A shunt motor, supplied at 250 V, runs at 900 r/min when the armature current is 30 A. The resistance of the armature circuit is 0.4 Ω. Calculate the resistance required in series with the armature to reduce the speed to 600 r/min, assuming that the armature current is then 20 A.

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Question: 40.1

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Question: 40.8

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Question: 40.7

A shunt motor is running at 626 r/min (Example 40.2) when taking an armature current of 50 A from a 440 V supply. The armature circuit has a resistance of 0.28 Ω. If the flux is suddenly reduced by 5 per cent, find: (a) the maximum value to which the current increases momentarily and the ratio of ...

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Question: 40.6

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Question: 40.4

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\begin{aligned}\text { (a) } \text { Gener...

Question: 40.3

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Question: 40.2

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