In a D.C. machine the current per brush arm should not be more than_____________?
Correct answer: D. 400 A
- A. 100 A
- B. 200 A
- C. 300 A
- D. 400 A
Explanation
The current carried by one brush arm is normally limited to about 400 A to prevent excessive heating and current density at the brushes and commutator. Thus, 400 A is the usual maximum value used in this design rule.
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