John Bachtel wrote: >> In 1957 and 1958, after graduating from Kenmore High School, near >> Buffalo, I was a turbine operator at Niagara Mohawk's Charles R. Huntley >> Steam station in Tonawanda, on the Niagara River. We were still >> operating units 25 hz 24, 25 and 26 and a reversable frequency changer. >> Total cap. was abt. 200 MW, alongside 1000 MW of 60 Hz power in the >> newer sections of the plant. Operation varied with the business >> climate, from full bore 24/7 to daily startup/ shutdown, occasionally >> with only one unit. Interesting work ... I got to do the throttle ups >> and enjoy the synchrozation process during startup. It could get >> dicey with our 30-50 year old equipment and synchroscope like a giant >> clock up on the wall. Equally exciting were sudden power dumps as >> happened during severe weather. Big building quake, followed by opening >> of steam safety valves atop the adjoining boiler house. > Who bought this 25Hz power?
Probably transit systems. The New York City subways operated on DC, created from rectified AC in the 25-30 Hz range. Probably still do.
Michael D. Sullivan Bethesda, MD (USA) (Replace "example.invalid" with "com" in my address.)