Stability characteristics of alternators

David Hall: As a designer of electrical machinery, I feel that this paper is valuable to the users of machinery because it points out some of the factors which are more or less concealed. We have specifications covering machines which do not cover the factors presented here and these factors are in many cases as important as the outstanding specifications of temperature and efficiency. We have pointed out in Mr. Shirley´s paper certain “red flags” beyond which the designer knows his machine will “lie down.” It is very useful to have those red flags placed before the designer.