Power plant auxiliaries and their relation to heat balance

H. W. Brooks (by letter): Mr. Penniman´s paper is of intense interest to many designers now working on new plant construction. There is, however, a vast field for application for heat-balancing devices in plants designed prior to the last three to five years as there are undoubtedly enormous losses taking place in many of these older plants owing to lack of proper heat balance. In private consulting practise last year the writer encountered a very interesting problem of this character in the plant of the Chicago, Aurora and Elgin Railroad Co. at Batavia, Ill., where a dual-drive exciter set of 300kw. capacity was finally designed in cooperation with the manufacturer. The steam end consisted of a 200 lb. pressure, 150-deg. superheat, non-condensing, direct-connected turbine of the impulse type, while the electric drive end consisted of a three-phase, 25-cycle, 2300-volt, phase-wound, induction motor, both machines being directconnected to the 300 kw. generator mounted between them and functioning at 750 rev. per min.