Discussion on “phenomena accompanying transmission with some types of star transformer connections” (Robinson), San Francisco, Cal., Sept. 17, 1915. (see proceedings for August, 1915)

Harris J. Ryan: In cases I and II: The author says that the abnormal condition “is explainable by a periodically reversing leg,” yet there is nothing in the paper nor in common knowledge to enable one to understand just what this “leg” is and what cause made it reverse. The author does not state for case III whether the abnormal condition was temporary or stable, a matter obviously of great importance. In explanation of the formation of the in-phase double frequency e. m. fs. applied between line and ground having effective values of four times the line voltage, “two sine wave e. m. fs. of normal frequency” are assumed to interact to form their product and thus to develop a double frequency resultant. Yet it is fixed knowledge that e. m. fs. interact to add or subtract and never to form a product-resultant. Double frequencies are produced only by products and never by additions or subtractions. Matters of this sort are not in accord with the statement in the abstract of the paper that the “data are omitted from the text to a large extent because the details could not add materially to the discussion.” The abnormal formation of large in-phase double frequency e. m. fs. applied from line to ground in a recognized system of transformer connections is a matter of importance. Conclusion VI should not go unchallenged for the reason that no demonstration in this paper appears to be of such a character as to lead “to the comprehensive understanding of the possibilities and impossibilities” therein referred to.