Abstract :
C. O. Werres (General Electric Company, Schenectady, N. Y.): One point which has been mentioned by Messrs. Gebelein and Elzi should be given more consideration sooner or later. I refer to the saturation that occurs in relays when they are subjected to overcurrents. This, of course, changes their impedance so that characteristics determined by either test or calculation which are usually made on the basis of nonsaturating burdens are not correct. Fortunately, the actual burden is less than the supposed burden and hence the transformer is better than indicated by the test or calculation. Offhand this does not sound too serious and it is not, if, for example, the errors in all transformers involved in a given setup using a percentage differential relay are kept below the relay setting. However, if this should not be done, it is conceivable that the effect of saturation of the burden might effect one transformer more than another to such an extent as to cause trouble.
