If a self excited D.C. generator after being installed, fails to build up on its first trial run, the first thing to do is to______________?
Correct answer: A. reverse the field connections
- A. reverse the field connections
- B. increase the field resistance
- C. increase the speed of primemover
- D. check armature insulation resistance
Explanation
A self-excited generator needs residual magnetism of the correct polarity to begin voltage build-up; reversing the field connections corrects an opposing field polarity. Increasing speed may help marginal build-up, but it is not the first corrective check in this standard case.
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