25 Hz power

> We were still operating units 25 hz 24, 25 and 26 and a reversable

>> frequency changer. > Who bought this 25Hz power?

IIRC, and somebody please correct me if I'm wrong, 25Hz power was used even in residential settings up into the early 50's in some parts of eastern Canada.

In NYC up into the 70's at least, power for two of the subway divisions (BMT and IRT) was generated at 25Hz but converted to DC in the field. However, I very distinctly remember the flicker of the incandescent lamps in some of the BMT stations in the 60's, as these were operated from the unrectified 25Hz source. I do remember that some people claimed they could not see this flicker, but it was very obvious, to me, anyway.

As another trivia point, commercial DC power was still available to some grandfathered customers in parts of Manhattan until just a few years ago.

Reply to
Loading thread data ...

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.